| 1 | // Copyright 2014 The Flutter Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | /// @docImport 'package:flutter/services.dart'; |
| 6 | /// @docImport 'package:flutter/widgets.dart'; |
| 7 | /// |
| 8 | /// @docImport 'binding.dart'; |
| 9 | /// @docImport 'object.dart'; |
| 10 | /// @docImport 'performance_overlay.dart'; |
| 11 | /// @docImport 'proxy_box.dart'; |
| 12 | /// @docImport 'view.dart'; |
| 13 | library; |
| 14 | |
| 15 | import 'dart:ui' as ui; |
| 16 | |
| 17 | import 'package:flutter/foundation.dart'; |
| 18 | import 'package:flutter/gestures.dart'; |
| 19 | import 'package:flutter/painting.dart'; |
| 20 | import 'package:flutter/scheduler.dart'; |
| 21 | import 'package:vector_math/vector_math_64.dart'; |
| 22 | |
| 23 | import 'debug.dart'; |
| 24 | |
| 25 | /// Information collected for an annotation that is found in the layer tree. |
| 26 | /// |
| 27 | /// See also: |
| 28 | /// |
| 29 | /// * [Layer.findAnnotations], which create and use objects of this class. |
| 30 | @immutable |
| 31 | class AnnotationEntry<T> { |
| 32 | /// Create an entry of found annotation by providing the object and related |
| 33 | /// information. |
| 34 | const AnnotationEntry({required this.annotation, required this.localPosition}); |
| 35 | |
| 36 | /// The annotation object that is found. |
| 37 | final T annotation; |
| 38 | |
| 39 | /// The target location described by the local coordinate space of the |
| 40 | /// annotation object. |
| 41 | final Offset localPosition; |
| 42 | |
| 43 | @override |
| 44 | String toString() { |
| 45 | return '${objectRuntimeType(this, 'AnnotationEntry')} (annotation:$annotation , localPosition:$localPosition )'; |
| 46 | } |
| 47 | } |
| 48 | |
| 49 | /// Information collected about a list of annotations that are found in the |
| 50 | /// layer tree. |
| 51 | /// |
| 52 | /// See also: |
| 53 | /// |
| 54 | /// * [AnnotationEntry], which are members of this class. |
| 55 | /// * [Layer.findAllAnnotations], and [Layer.findAnnotations], which create and |
| 56 | /// use an object of this class. |
| 57 | class AnnotationResult<T> { |
| 58 | final List<AnnotationEntry<T>> _entries = <AnnotationEntry<T>>[]; |
| 59 | |
| 60 | /// Add a new entry to the end of the result. |
| 61 | /// |
| 62 | /// Usually, entries should be added in order from most specific to least |
| 63 | /// specific, typically during an upward walk of the tree. |
| 64 | void add(AnnotationEntry<T> entry) => _entries.add(entry); |
| 65 | |
| 66 | /// An unmodifiable list of [AnnotationEntry] objects recorded. |
| 67 | /// |
| 68 | /// The first entry is the most specific, typically the one at the leaf of |
| 69 | /// tree. |
| 70 | Iterable<AnnotationEntry<T>> get entries => _entries; |
| 71 | |
| 72 | /// An unmodifiable list of annotations recorded. |
| 73 | /// |
| 74 | /// The first entry is the most specific, typically the one at the leaf of |
| 75 | /// tree. |
| 76 | /// |
| 77 | /// It is similar to [entries] but does not contain other information. |
| 78 | Iterable<T> get annotations { |
| 79 | return _entries.map((AnnotationEntry<T> entry) => entry.annotation); |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | /// A composited layer. |
| 84 | /// |
| 85 | /// During painting, the render tree generates a tree of composited layers that |
| 86 | /// are uploaded into the engine and displayed by the compositor. This class is |
| 87 | /// the base class for all composited layers. |
| 88 | /// |
| 89 | /// Most layers can have their properties mutated, and layers can be moved to |
| 90 | /// different parents. The scene must be explicitly recomposited after such |
| 91 | /// changes are made; the layer tree does not maintain its own dirty state. |
| 92 | /// |
| 93 | /// To composite the tree, create a [ui.SceneBuilder] object using |
| 94 | /// [RendererBinding.createSceneBuilder], pass it to the root [Layer] object's |
| 95 | /// [addToScene] method, and then call [ui.SceneBuilder.build] to obtain a [ui.Scene]. |
| 96 | /// A [ui.Scene] can then be painted using [ui.FlutterView.render]. |
| 97 | /// |
| 98 | /// ## Memory |
| 99 | /// |
| 100 | /// Layers retain resources between frames to speed up rendering. A layer will |
| 101 | /// retain these resources until all [LayerHandle]s referring to the layer have |
| 102 | /// nulled out their references. |
| 103 | /// |
| 104 | /// Layers must not be used after disposal. If a RenderObject needs to maintain |
| 105 | /// a layer for later usage, it must create a handle to that layer. This is |
| 106 | /// handled automatically for the [RenderObject.layer] property, but additional |
| 107 | /// layers must use their own [LayerHandle]. |
| 108 | /// |
| 109 | /// {@tool snippet} |
| 110 | /// |
| 111 | /// This [RenderObject] is a repaint boundary that pushes an additional |
| 112 | /// [ClipRectLayer]. |
| 113 | /// |
| 114 | /// ```dart |
| 115 | /// class ClippingRenderObject extends RenderBox { |
| 116 | /// final LayerHandle<ClipRectLayer> _clipRectLayer = LayerHandle<ClipRectLayer>(); |
| 117 | /// |
| 118 | /// @override |
| 119 | /// bool get isRepaintBoundary => true; // The [layer] property will be used. |
| 120 | /// |
| 121 | /// @override |
| 122 | /// void paint(PaintingContext context, Offset offset) { |
| 123 | /// _clipRectLayer.layer = context.pushClipRect( |
| 124 | /// needsCompositing, |
| 125 | /// offset, |
| 126 | /// Offset.zero & size, |
| 127 | /// super.paint, |
| 128 | /// oldLayer: _clipRectLayer.layer, |
| 129 | /// ); |
| 130 | /// } |
| 131 | /// |
| 132 | /// @override |
| 133 | /// void dispose() { |
| 134 | /// _clipRectLayer.layer = null; |
| 135 | /// super.dispose(); |
| 136 | /// } |
| 137 | /// } |
| 138 | /// ``` |
| 139 | /// {@end-tool} |
| 140 | /// See also: |
| 141 | /// |
| 142 | /// * [RenderView.compositeFrame], which implements this recomposition protocol |
| 143 | /// for painting [RenderObject] trees on the display. |
| 144 | abstract class Layer with DiagnosticableTreeMixin { |
| 145 | /// Creates an instance of Layer. |
| 146 | Layer() { |
| 147 | assert(debugMaybeDispatchCreated('rendering', 'Layer', this)); |
| 148 | } |
| 149 | |
| 150 | final Map<int, VoidCallback> _callbacks = <int, VoidCallback>{}; |
| 151 | static int _nextCallbackId = 0; |
| 152 | |
| 153 | /// Whether the subtree rooted at this layer has any composition callback |
| 154 | /// observers. |
| 155 | /// |
| 156 | /// This only evaluates to true if the subtree rooted at this node has |
| 157 | /// observers. For example, it may evaluate to true on a parent node but false |
| 158 | /// on a child if the parent has observers but the child does not. |
| 159 | /// |
| 160 | /// See also: |
| 161 | /// |
| 162 | /// * [Layer.addCompositionCallback]. |
| 163 | bool get subtreeHasCompositionCallbacks => _compositionCallbackCount > 0; |
| 164 | |
| 165 | int _compositionCallbackCount = 0; |
| 166 | void _updateSubtreeCompositionObserverCount(int delta) { |
| 167 | assert(delta != 0); |
| 168 | _compositionCallbackCount += delta; |
| 169 | assert(_compositionCallbackCount >= 0); |
| 170 | parent?._updateSubtreeCompositionObserverCount(delta); |
| 171 | } |
| 172 | |
| 173 | void _fireCompositionCallbacks({required bool includeChildren}) { |
| 174 | if (_callbacks.isEmpty) { |
| 175 | return; |
| 176 | } |
| 177 | for (final VoidCallback callback in List<VoidCallback>.of(_callbacks.values)) { |
| 178 | callback(); |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | bool _debugMutationsLocked = false; |
| 183 | |
| 184 | /// Whether or not this layer, or any child layers, can be rasterized with |
| 185 | /// [ui.Scene.toImage] or [ui.Scene.toImageSync]. |
| 186 | /// |
| 187 | /// If `false`, calling the above methods may yield an image which is |
| 188 | /// incomplete. |
| 189 | /// |
| 190 | /// This value may change throughout the lifetime of the object, as the |
| 191 | /// child layers themselves are added or removed. |
| 192 | bool supportsRasterization() { |
| 193 | return true; |
| 194 | } |
| 195 | |
| 196 | /// Describes the clip that would be applied to contents of this layer, |
| 197 | /// if any. |
| 198 | Rect? describeClipBounds() => null; |
| 199 | |
| 200 | /// Adds a callback for when the layer tree that this layer is part of gets |
| 201 | /// composited, or when it is detached and will not be rendered again. |
| 202 | /// |
| 203 | /// This callback will fire even if an ancestor layer is added with retained |
| 204 | /// rendering, meaning that it will fire even if this layer gets added to the |
| 205 | /// scene via some call to [ui.SceneBuilder.addRetained] on one of its |
| 206 | /// ancestor layers. |
| 207 | /// |
| 208 | /// The callback receives a reference to this layer. The recipient must not |
| 209 | /// mutate the layer during the scope of the callback, but may traverse the |
| 210 | /// tree to find information about the current transform or clip. The layer |
| 211 | /// may not be [attached] anymore in this state, but even if it is detached it |
| 212 | /// may still have an also detached parent it can visit. |
| 213 | /// |
| 214 | /// If new callbacks are added or removed within the [callback], the new |
| 215 | /// callbacks will fire (or stop firing) on the _next_ compositing event. |
| 216 | /// |
| 217 | /// {@template flutter.rendering.Layer.compositionCallbacks} |
| 218 | /// Composition callbacks are useful in place of pushing a layer that would |
| 219 | /// otherwise try to observe the layer tree without actually affecting |
| 220 | /// compositing. For example, a composition callback may be used to observe |
| 221 | /// the total transform and clip of the current container layer to determine |
| 222 | /// whether a render object drawn into it is visible or not. |
| 223 | /// |
| 224 | /// Calling the returned callback will remove [callback] from the composition |
| 225 | /// callbacks. |
| 226 | /// {@endtemplate} |
| 227 | VoidCallback addCompositionCallback(CompositionCallback callback) { |
| 228 | _updateSubtreeCompositionObserverCount(1); |
| 229 | final int callbackId = _nextCallbackId += 1; |
| 230 | _callbacks[callbackId] = () { |
| 231 | assert(() { |
| 232 | _debugMutationsLocked = true; |
| 233 | return true; |
| 234 | }()); |
| 235 | callback(this); |
| 236 | assert(() { |
| 237 | _debugMutationsLocked = false; |
| 238 | return true; |
| 239 | }()); |
| 240 | }; |
| 241 | return () { |
| 242 | assert(debugDisposed || _callbacks.containsKey(callbackId)); |
| 243 | _callbacks.remove(callbackId); |
| 244 | _updateSubtreeCompositionObserverCount(-1); |
| 245 | }; |
| 246 | } |
| 247 | |
| 248 | /// If asserts are enabled, returns whether [dispose] has |
| 249 | /// been called since the last time any retained resources were created. |
| 250 | /// |
| 251 | /// Throws an exception if asserts are disabled. |
| 252 | bool get debugDisposed { |
| 253 | late bool disposed; |
| 254 | assert(() { |
| 255 | disposed = _debugDisposed; |
| 256 | return true; |
| 257 | }()); |
| 258 | return disposed; |
| 259 | } |
| 260 | |
| 261 | bool _debugDisposed = false; |
| 262 | |
| 263 | /// Set when this layer is appended to a [ContainerLayer], and |
| 264 | /// unset when it is removed. |
| 265 | /// |
| 266 | /// This cannot be set from [attach] or [detach] which is called when an |
| 267 | /// entire subtree is attached to or detached from an owner. Layers may be |
| 268 | /// appended to or removed from a [ContainerLayer] regardless of whether they |
| 269 | /// are attached or detached, and detaching a layer from an owner does not |
| 270 | /// imply that it has been removed from its parent. |
| 271 | final LayerHandle<Layer> _parentHandle = LayerHandle<Layer>(); |
| 272 | |
| 273 | /// Incremented by [LayerHandle]. |
| 274 | int _refCount = 0; |
| 275 | |
| 276 | /// Called by [LayerHandle]. |
| 277 | void _unref() { |
| 278 | assert(!_debugMutationsLocked); |
| 279 | assert(_refCount > 0); |
| 280 | _refCount -= 1; |
| 281 | if (_refCount == 0) { |
| 282 | dispose(); |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | /// Returns the number of objects holding a [LayerHandle] to this layer. |
| 287 | /// |
| 288 | /// This method throws if asserts are disabled. |
| 289 | int get debugHandleCount { |
| 290 | late int count; |
| 291 | assert(() { |
| 292 | count = _refCount; |
| 293 | return true; |
| 294 | }()); |
| 295 | return count; |
| 296 | } |
| 297 | |
| 298 | /// Clears any retained resources that this layer holds. |
| 299 | /// |
| 300 | /// This method must dispose resources such as [ui.EngineLayer] and [ui.Picture] |
| 301 | /// objects. The layer is still usable after this call, but any graphics |
| 302 | /// related resources it holds will need to be recreated. |
| 303 | /// |
| 304 | /// This method _only_ disposes resources for this layer. For example, if it |
| 305 | /// is a [ContainerLayer], it does not dispose resources of any children. |
| 306 | /// However, [ContainerLayer]s do remove any children they have when |
| 307 | /// this method is called, and if this layer was the last holder of a removed |
| 308 | /// child handle, the child may recursively clean up its resources. |
| 309 | /// |
| 310 | /// This method automatically gets called when all outstanding [LayerHandle]s |
| 311 | /// are disposed. [LayerHandle] objects are typically held by the [parent] |
| 312 | /// layer of this layer and any [RenderObject]s that participated in creating |
| 313 | /// it. |
| 314 | /// |
| 315 | /// After calling this method, the object is unusable. |
| 316 | @mustCallSuper |
| 317 | @protected |
| 318 | @visibleForTesting |
| 319 | void dispose() { |
| 320 | assert(!_debugMutationsLocked); |
| 321 | assert( |
| 322 | !_debugDisposed, |
| 323 | 'Layers must only be disposed once. This is typically handled by ' |
| 324 | 'LayerHandle and createHandle. Subclasses should not directly call ' |
| 325 | 'dispose, except to call super.dispose() in an overridden dispose ' |
| 326 | 'method. Tests must only call dispose once.', |
| 327 | ); |
| 328 | assert(() { |
| 329 | assert( |
| 330 | _refCount == 0, |
| 331 | 'Do not directly call dispose on a$runtimeType . Instead, ' |
| 332 | 'use createHandle and LayerHandle.dispose.', |
| 333 | ); |
| 334 | _debugDisposed = true; |
| 335 | return true; |
| 336 | }()); |
| 337 | assert(debugMaybeDispatchDisposed(this)); |
| 338 | _engineLayer?.dispose(); |
| 339 | _engineLayer = null; |
| 340 | } |
| 341 | |
| 342 | /// This layer's parent in the layer tree. |
| 343 | /// |
| 344 | /// The [parent] of the root node in the layer tree is null. |
| 345 | /// |
| 346 | /// Only subclasses of [ContainerLayer] can have children in the layer tree. |
| 347 | /// All other layer classes are used for leaves in the layer tree. |
| 348 | ContainerLayer? get parent => _parent; |
| 349 | ContainerLayer? _parent; |
| 350 | |
| 351 | // Whether this layer has any changes since its last call to [addToScene]. |
| 352 | // |
| 353 | // Initialized to true as a new layer has never called [addToScene], and is |
| 354 | // set to false after calling [addToScene]. The value can become true again |
| 355 | // if [markNeedsAddToScene] is called, or when [updateSubtreeNeedsAddToScene] |
| 356 | // is called on this layer or on an ancestor layer. |
| 357 | // |
| 358 | // The values of [_needsAddToScene] in a tree of layers are said to be |
| 359 | // _consistent_ if every layer in the tree satisfies the following: |
| 360 | // |
| 361 | // - If [alwaysNeedsAddToScene] is true, then [_needsAddToScene] is also true. |
| 362 | // - If [_needsAddToScene] is true and [parent] is not null, then |
| 363 | // `parent._needsAddToScene` is true. |
| 364 | // |
| 365 | // Typically, this value is set during the paint phase and during compositing. |
| 366 | // During the paint phase render objects create new layers and call |
| 367 | // [markNeedsAddToScene] on existing layers, causing this value to become |
| 368 | // true. After the paint phase the tree may be in an inconsistent state. |
| 369 | // During compositing [ContainerLayer.buildScene] first calls |
| 370 | // [updateSubtreeNeedsAddToScene] to bring this tree to a consistent state, |
| 371 | // then it calls [addToScene], and finally sets this field to false. |
| 372 | bool _needsAddToScene = true; |
| 373 | |
| 374 | /// Mark that this layer has changed and [addToScene] needs to be called. |
| 375 | @protected |
| 376 | @visibleForTesting |
| 377 | void markNeedsAddToScene() { |
| 378 | assert(!_debugMutationsLocked); |
| 379 | assert( |
| 380 | !alwaysNeedsAddToScene, |
| 381 | '$runtimeType with alwaysNeedsAddToScene set called markNeedsAddToScene.\n' |
| 382 | "The layer's alwaysNeedsAddToScene is set to true, and therefore it should not call markNeedsAddToScene.", |
| 383 | ); |
| 384 | assert(!_debugDisposed); |
| 385 | |
| 386 | // Already marked. Short-circuit. |
| 387 | if (_needsAddToScene) { |
| 388 | return; |
| 389 | } |
| 390 | |
| 391 | _needsAddToScene = true; |
| 392 | } |
| 393 | |
| 394 | /// Mark that this layer is in sync with engine. |
| 395 | /// |
| 396 | /// This is for debugging and testing purposes only. In release builds |
| 397 | /// this method has no effect. |
| 398 | @visibleForTesting |
| 399 | void debugMarkClean() { |
| 400 | assert(!_debugMutationsLocked); |
| 401 | assert(() { |
| 402 | _needsAddToScene = false; |
| 403 | return true; |
| 404 | }()); |
| 405 | } |
| 406 | |
| 407 | /// Subclasses may override this to true to disable retained rendering. |
| 408 | @protected |
| 409 | bool get alwaysNeedsAddToScene => false; |
| 410 | |
| 411 | /// Whether this or any descendant layer in the subtree needs [addToScene]. |
| 412 | /// |
| 413 | /// This is for debug and test purpose only. It only becomes valid after |
| 414 | /// calling [updateSubtreeNeedsAddToScene]. |
| 415 | @visibleForTesting |
| 416 | bool? get debugSubtreeNeedsAddToScene { |
| 417 | bool? result; |
| 418 | assert(() { |
| 419 | result = _needsAddToScene; |
| 420 | return true; |
| 421 | }()); |
| 422 | return result; |
| 423 | } |
| 424 | |
| 425 | /// Stores the engine layer created for this layer in order to reuse engine |
| 426 | /// resources across frames for better app performance. |
| 427 | /// |
| 428 | /// This value may be passed to [ui.SceneBuilder.addRetained] to communicate |
| 429 | /// to the engine that nothing in this layer or any of its descendants |
| 430 | /// changed. The native engine could, for example, reuse the texture rendered |
| 431 | /// in a previous frame. The web engine could, for example, reuse the HTML |
| 432 | /// DOM nodes created for a previous frame. |
| 433 | /// |
| 434 | /// This value may be passed as `oldLayer` argument to a "push" method to |
| 435 | /// communicate to the engine that a layer is updating a previously rendered |
| 436 | /// layer. The web engine could, for example, update the properties of |
| 437 | /// previously rendered HTML DOM nodes rather than creating new nodes. |
| 438 | @protected |
| 439 | @visibleForTesting |
| 440 | ui.EngineLayer? get engineLayer => _engineLayer; |
| 441 | |
| 442 | /// Sets the engine layer used to render this layer. |
| 443 | /// |
| 444 | /// Typically this field is set to the value returned by [addToScene], which |
| 445 | /// in turn returns the engine layer produced by one of [ui.SceneBuilder]'s |
| 446 | /// "push" methods, such as [ui.SceneBuilder.pushOpacity]. |
| 447 | @protected |
| 448 | @visibleForTesting |
| 449 | set engineLayer(ui.EngineLayer? value) { |
| 450 | assert(!_debugMutationsLocked); |
| 451 | assert(!_debugDisposed); |
| 452 | |
| 453 | _engineLayer?.dispose(); |
| 454 | _engineLayer = value; |
| 455 | if (!alwaysNeedsAddToScene) { |
| 456 | // The parent must construct a new engine layer to add this layer to, and |
| 457 | // so we mark it as needing [addToScene]. |
| 458 | // |
| 459 | // This is designed to handle two situations: |
| 460 | // |
| 461 | // 1. When rendering the complete layer tree as normal. In this case we |
| 462 | // call child `addToScene` methods first, then we call `set engineLayer` |
| 463 | // for the parent. The children will call `markNeedsAddToScene` on the |
| 464 | // parent to signal that they produced new engine layers and therefore |
| 465 | // the parent needs to update. In this case, the parent is already adding |
| 466 | // itself to the scene via [addToScene], and so after it's done, its |
| 467 | // `set engineLayer` is called and it clears the `_needsAddToScene` flag. |
| 468 | // |
| 469 | // 2. When rendering an interior layer (e.g. `OffsetLayer.toImage`). In |
| 470 | // this case we call `addToScene` for one of the children but not the |
| 471 | // parent, i.e. we produce new engine layers for children but not for the |
| 472 | // parent. Here the children will mark the parent as needing |
| 473 | // `addToScene`, but the parent does not clear the flag until some future |
| 474 | // frame decides to render it, at which point the parent knows that it |
| 475 | // cannot retain its engine layer and will call `addToScene` again. |
| 476 | if (parent != null && !parent!.alwaysNeedsAddToScene) { |
| 477 | parent!.markNeedsAddToScene(); |
| 478 | } |
| 479 | } |
| 480 | } |
| 481 | |
| 482 | ui.EngineLayer? _engineLayer; |
| 483 | |
| 484 | /// Traverses the layer subtree starting from this layer and determines whether it needs [addToScene]. |
| 485 | /// |
| 486 | /// A layer needs [addToScene] if any of the following is true: |
| 487 | /// |
| 488 | /// - [alwaysNeedsAddToScene] is true. |
| 489 | /// - [markNeedsAddToScene] has been called. |
| 490 | /// - Any of its descendants need [addToScene]. |
| 491 | /// |
| 492 | /// [ContainerLayer] overrides this method to recursively call it on its children. |
| 493 | @protected |
| 494 | @visibleForTesting |
| 495 | void updateSubtreeNeedsAddToScene() { |
| 496 | assert(!_debugMutationsLocked); |
| 497 | _needsAddToScene = _needsAddToScene || alwaysNeedsAddToScene; |
| 498 | } |
| 499 | |
| 500 | /// The owner for this layer (null if unattached). |
| 501 | /// |
| 502 | /// The entire layer tree that this layer belongs to will have the same owner. |
| 503 | /// |
| 504 | /// Typically the owner is a [RenderView]. |
| 505 | Object? get owner => _owner; |
| 506 | Object? _owner; |
| 507 | |
| 508 | /// Whether the layer tree containing this layer is attached to an owner. |
| 509 | /// |
| 510 | /// This becomes true during the call to [attach]. |
| 511 | /// |
| 512 | /// This becomes false during the call to [detach]. |
| 513 | bool get attached => _owner != null; |
| 514 | |
| 515 | /// Mark this layer as attached to the given owner. |
| 516 | /// |
| 517 | /// Typically called only from the [parent]'s [attach] method, and by the |
| 518 | /// [owner] to mark the root of a tree as attached. |
| 519 | /// |
| 520 | /// Subclasses with children should override this method to |
| 521 | /// [attach] all their children to the same [owner] |
| 522 | /// after calling the inherited method, as in `super.attach(owner)`. |
| 523 | @mustCallSuper |
| 524 | void attach(covariant Object owner) { |
| 525 | assert(_owner == null); |
| 526 | _owner = owner; |
| 527 | } |
| 528 | |
| 529 | /// Mark this layer as detached from its owner. |
| 530 | /// |
| 531 | /// Typically called only from the [parent]'s [detach], and by the [owner] to |
| 532 | /// mark the root of a tree as detached. |
| 533 | /// |
| 534 | /// Subclasses with children should override this method to |
| 535 | /// [detach] all their children after calling the inherited method, |
| 536 | /// as in `super.detach()`. |
| 537 | @mustCallSuper |
| 538 | void detach() { |
| 539 | assert(_owner != null); |
| 540 | _owner = null; |
| 541 | assert(parent == null || attached == parent!.attached); |
| 542 | } |
| 543 | |
| 544 | /// The depth of this layer in the layer tree. |
| 545 | /// |
| 546 | /// The depth of nodes in a tree monotonically increases as you traverse down |
| 547 | /// the tree. There's no guarantee regarding depth between siblings. |
| 548 | /// |
| 549 | /// The depth is used to ensure that nodes are processed in depth order. |
| 550 | int get depth => _depth; |
| 551 | int _depth = 0; |
| 552 | |
| 553 | /// Adjust the [depth] of this node's children, if any. |
| 554 | /// |
| 555 | /// Override this method in subclasses with child nodes to call |
| 556 | /// [ContainerLayer.redepthChild] for each child. Do not call this method |
| 557 | /// directly. |
| 558 | @protected |
| 559 | void redepthChildren() { |
| 560 | // ContainerLayer provides an implementation since its the only one that |
| 561 | // can actually have children. |
| 562 | } |
| 563 | |
| 564 | /// This layer's next sibling in the parent layer's child list. |
| 565 | Layer? get nextSibling => _nextSibling; |
| 566 | Layer? _nextSibling; |
| 567 | |
| 568 | /// This layer's previous sibling in the parent layer's child list. |
| 569 | Layer? get previousSibling => _previousSibling; |
| 570 | Layer? _previousSibling; |
| 571 | |
| 572 | /// Removes this layer from its parent layer's child list. |
| 573 | /// |
| 574 | /// This has no effect if the layer's parent is already null. |
| 575 | @mustCallSuper |
| 576 | void remove() { |
| 577 | assert(!_debugMutationsLocked); |
| 578 | parent?._removeChild(this); |
| 579 | } |
| 580 | |
| 581 | /// Search this layer and its subtree for annotations of type `S` at the |
| 582 | /// location described by `localPosition`. |
| 583 | /// |
| 584 | /// This method is called by the default implementation of [find] and |
| 585 | /// [findAllAnnotations]. Override this method to customize how the layer |
| 586 | /// should search for annotations, or if the layer has its own annotations to |
| 587 | /// add. |
| 588 | /// |
| 589 | /// The default implementation always returns `false`, which means neither |
| 590 | /// the layer nor its children has annotations, and the annotation search |
| 591 | /// is not absorbed either (see below for explanation). |
| 592 | /// |
| 593 | /// ## About layer annotations |
| 594 | /// |
| 595 | /// {@template flutter.rendering.Layer.findAnnotations.aboutAnnotations} |
| 596 | /// An annotation is an optional object of any type that can be carried with a |
| 597 | /// layer. An annotation can be found at a location as long as the owner layer |
| 598 | /// contains the location and is walked to. |
| 599 | /// |
| 600 | /// The annotations are searched by first visiting each child recursively, |
| 601 | /// then this layer, resulting in an order from visually front to back. |
| 602 | /// Annotations must meet the given restrictions, such as type and position. |
| 603 | /// |
| 604 | /// The common way for a value to be found here is by pushing an |
| 605 | /// [AnnotatedRegionLayer] into the layer tree, or by adding the desired |
| 606 | /// annotation by overriding [findAnnotations]. |
| 607 | /// {@endtemplate} |
| 608 | /// |
| 609 | /// ## Parameters and return value |
| 610 | /// |
| 611 | /// The [result] parameter is where the method outputs the resulting |
| 612 | /// annotations. New annotations found during the walk are added to the tail. |
| 613 | /// |
| 614 | /// The [onlyFirst] parameter indicates that, if true, the search will stop |
| 615 | /// when it finds the first qualified annotation; otherwise, it will walk the |
| 616 | /// entire subtree. |
| 617 | /// |
| 618 | /// The return value indicates the opacity of this layer and its subtree at |
| 619 | /// this position. If it returns true, then this layer's parent should skip |
| 620 | /// the children behind this layer. In other words, it is opaque to this type |
| 621 | /// of annotation and has absorbed the search so that its siblings behind it |
| 622 | /// are not aware of the search. If the return value is false, then the parent |
| 623 | /// might continue with other siblings. |
| 624 | /// |
| 625 | /// The return value does not affect whether the parent adds its own |
| 626 | /// annotations; in other words, if a layer is supposed to add an annotation, |
| 627 | /// it will always add it even if its children are opaque to this type of |
| 628 | /// annotation. However, the opacity that the parents return might be affected |
| 629 | /// by their children, hence making all of its ancestors opaque to this type |
| 630 | /// of annotation. |
| 631 | @protected |
| 632 | bool findAnnotations<S extends Object>( |
| 633 | AnnotationResult<S> result, |
| 634 | Offset localPosition, { |
| 635 | required bool onlyFirst, |
| 636 | }) { |
| 637 | return false; |
| 638 | } |
| 639 | |
| 640 | /// Search this layer and its subtree for the first annotation of type `S` |
| 641 | /// under the point described by `localPosition`. |
| 642 | /// |
| 643 | /// Returns null if no matching annotations are found. |
| 644 | /// |
| 645 | /// By default this method calls [findAnnotations] with `onlyFirst: |
| 646 | /// true` and returns the annotation of the first result. Prefer overriding |
| 647 | /// [findAnnotations] instead of this method, because during an annotation |
| 648 | /// search, only [findAnnotations] is recursively called, while custom |
| 649 | /// behavior in this method is ignored. |
| 650 | /// |
| 651 | /// ## About layer annotations |
| 652 | /// |
| 653 | /// {@macro flutter.rendering.Layer.findAnnotations.aboutAnnotations} |
| 654 | /// |
| 655 | /// See also: |
| 656 | /// |
| 657 | /// * [findAllAnnotations], which is similar but returns all annotations found |
| 658 | /// at the given position. |
| 659 | /// * [AnnotatedRegionLayer], for placing values in the layer tree. |
| 660 | S? find<S extends Object>(Offset localPosition) { |
| 661 | final AnnotationResult<S> result = AnnotationResult<S>(); |
| 662 | findAnnotations<S>(result, localPosition, onlyFirst: true); |
| 663 | return result.entries.isEmpty ? null : result.entries.first.annotation; |
| 664 | } |
| 665 | |
| 666 | /// Search this layer and its subtree for all annotations of type `S` under |
| 667 | /// the point described by `localPosition`. |
| 668 | /// |
| 669 | /// Returns a result with empty entries if no matching annotations are found. |
| 670 | /// |
| 671 | /// By default this method calls [findAnnotations] with `onlyFirst: |
| 672 | /// false` and returns the annotations of its result. Prefer overriding |
| 673 | /// [findAnnotations] instead of this method, because during an annotation |
| 674 | /// search, only [findAnnotations] is recursively called, while custom |
| 675 | /// behavior in this method is ignored. |
| 676 | /// |
| 677 | /// ## About layer annotations |
| 678 | /// |
| 679 | /// {@macro flutter.rendering.Layer.findAnnotations.aboutAnnotations} |
| 680 | /// |
| 681 | /// See also: |
| 682 | /// |
| 683 | /// * [find], which is similar but returns the first annotation found at the |
| 684 | /// given position. |
| 685 | /// * [AnnotatedRegionLayer], for placing values in the layer tree. |
| 686 | AnnotationResult<S> findAllAnnotations<S extends Object>(Offset localPosition) { |
| 687 | final AnnotationResult<S> result = AnnotationResult<S>(); |
| 688 | findAnnotations<S>(result, localPosition, onlyFirst: false); |
| 689 | return result; |
| 690 | } |
| 691 | |
| 692 | /// Override this method to upload this layer to the engine. |
| 693 | @protected |
| 694 | void addToScene(ui.SceneBuilder builder); |
| 695 | |
| 696 | void _addToSceneWithRetainedRendering(ui.SceneBuilder builder) { |
| 697 | assert(!_debugMutationsLocked); |
| 698 | // There can't be a loop by adding a retained layer subtree whose |
| 699 | // _needsAddToScene is false. |
| 700 | // |
| 701 | // Proof by contradiction: |
| 702 | // |
| 703 | // If we introduce a loop, this retained layer must be appended to one of |
| 704 | // its descendant layers, say A. That means the child structure of A has |
| 705 | // changed so A's _needsAddToScene is true. This contradicts |
| 706 | // _needsAddToScene being false. |
| 707 | if (!_needsAddToScene && _engineLayer != null) { |
| 708 | builder.addRetained(_engineLayer!); |
| 709 | return; |
| 710 | } |
| 711 | addToScene(builder); |
| 712 | // Clearing the flag _after_ calling `addToScene`, not _before_. This is |
| 713 | // because `addToScene` calls children's `addToScene` methods, which may |
| 714 | // mark this layer as dirty. |
| 715 | _needsAddToScene = false; |
| 716 | } |
| 717 | |
| 718 | /// The object responsible for creating this layer. |
| 719 | /// |
| 720 | /// Defaults to the value of [RenderObject.debugCreator] for the render object |
| 721 | /// that created this layer. Used in debug messages. |
| 722 | Object? debugCreator; |
| 723 | |
| 724 | @override |
| 725 | String toStringShort() => '${super.toStringShort()} ${owner == null ?" DETACHED":""}'; |
| 726 | |
| 727 | @override |
| 728 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 729 | super.debugFillProperties(properties); |
| 730 | properties.add( |
| 731 | DiagnosticsProperty<Object>( |
| 732 | 'owner', |
| 733 | owner, |
| 734 | level: parent != null ? DiagnosticLevel.hidden : DiagnosticLevel.info, |
| 735 | defaultValue: null, |
| 736 | ), |
| 737 | ); |
| 738 | properties.add( |
| 739 | DiagnosticsProperty<Object?>( |
| 740 | 'creator', |
| 741 | debugCreator, |
| 742 | defaultValue: null, |
| 743 | level: DiagnosticLevel.debug, |
| 744 | ), |
| 745 | ); |
| 746 | if (_engineLayer != null) { |
| 747 | properties.add(DiagnosticsProperty<String>('engine layer', describeIdentity(_engineLayer))); |
| 748 | } |
| 749 | properties.add(DiagnosticsProperty<int>('handles', debugHandleCount)); |
| 750 | } |
| 751 | } |
| 752 | |
| 753 | /// A handle to prevent a [Layer]'s platform graphics resources from being |
| 754 | /// disposed. |
| 755 | /// |
| 756 | /// [Layer] objects retain native resources such as [ui.EngineLayer]s and [ui.Picture] |
| 757 | /// objects. These objects may in turn retain large chunks of texture memory, |
| 758 | /// either directly or indirectly. |
| 759 | /// |
| 760 | /// The layer's native resources must be retained as long as there is some |
| 761 | /// object that can add it to a scene. Typically, this is either its |
| 762 | /// [Layer.parent] or an undisposed [RenderObject] that will append it to a |
| 763 | /// [ContainerLayer]. Layers automatically hold a handle to their children, and |
| 764 | /// RenderObjects automatically hold a handle to their [RenderObject.layer] as |
| 765 | /// well as any [PictureLayer]s that they paint into using the |
| 766 | /// [PaintingContext.canvas]. A layer automatically releases its resources once |
| 767 | /// at least one handle has been acquired and all handles have been disposed. |
| 768 | /// [RenderObject]s that create additional layer objects must manually manage |
| 769 | /// the handles for that layer similarly to the implementation of |
| 770 | /// [RenderObject.layer]. |
| 771 | /// |
| 772 | /// A handle is automatically managed for [RenderObject.layer]. |
| 773 | /// |
| 774 | /// If a [RenderObject] creates layers in addition to its [RenderObject.layer] |
| 775 | /// and it intends to reuse those layers separately from [RenderObject.layer], |
| 776 | /// it must create a handle to that layer and dispose of it when the layer is |
| 777 | /// no longer needed. For example, if it re-creates or nulls out an existing |
| 778 | /// layer in [RenderObject.paint], it should dispose of the handle to the |
| 779 | /// old layer. It should also dispose of any layer handles it holds in |
| 780 | /// [RenderObject.dispose]. |
| 781 | /// |
| 782 | /// To dispose of a layer handle, set its [layer] property to null. |
| 783 | class LayerHandle<T extends Layer> { |
| 784 | /// Create a new layer handle, optionally referencing a [Layer]. |
| 785 | LayerHandle([this._layer]) { |
| 786 | if (_layer != null) { |
| 787 | _layer!._refCount += 1; |
| 788 | } |
| 789 | } |
| 790 | |
| 791 | T? _layer; |
| 792 | |
| 793 | /// The [Layer] whose resources this object keeps alive. |
| 794 | /// |
| 795 | /// Setting a new value or null will dispose the previously held layer if |
| 796 | /// there are no other open handles to that layer. |
| 797 | T? get layer => _layer; |
| 798 | |
| 799 | set layer(T? layer) { |
| 800 | assert( |
| 801 | layer?.debugDisposed != true, |
| 802 | 'Attempted to create a handle to an already disposed layer:$layer.', |
| 803 | ); |
| 804 | if (identical(layer, _layer)) { |
| 805 | return; |
| 806 | } |
| 807 | _layer?._unref(); |
| 808 | _layer = layer; |
| 809 | if (_layer != null) { |
| 810 | _layer!._refCount += 1; |
| 811 | } |
| 812 | } |
| 813 | |
| 814 | @override |
| 815 | String toString() =>'LayerHandle(${_layer != null ? _layer.toString() :'DISPOSED'})'; |
| 816 | } |
| 817 | |
| 818 | /// A composited layer containing a [ui.Picture]. |
| 819 | /// |
| 820 | /// Picture layers are always leaves in the layer tree. They are also |
| 821 | /// responsible for disposing of the [ui.Picture] object they hold. This is |
| 822 | /// typically done when their parent and all [RenderObject]s that participated |
| 823 | /// in painting the picture have been disposed. |
| 824 | class PictureLayer extends Layer { |
| 825 | /// Creates a leaf layer for the layer tree. |
| 826 | PictureLayer(this.canvasBounds); |
| 827 | |
| 828 | /// The bounds that were used for the canvas that drew this layer's [picture]. |
| 829 | /// |
| 830 | /// This is purely advisory. It is included in the information dumped with |
| 831 | /// [debugDumpLayerTree] (which can be triggered by pressing "L" when using |
| 832 | /// "flutter run" at the console), which can help debug why certain drawing |
| 833 | /// commands are being culled. |
| 834 | final Rect canvasBounds; |
| 835 | |
| 836 | /// The picture recorded for this layer. |
| 837 | /// |
| 838 | /// The picture's coordinate system matches this layer's coordinate system. |
| 839 | /// |
| 840 | /// The scene must be explicitly recomposited after this property is changed |
| 841 | /// (as described at [Layer]). |
| 842 | ui.Picture? get picture => _picture; |
| 843 | ui.Picture? _picture; |
| 844 | set picture(ui.Picture? picture) { |
| 845 | assert(!_debugDisposed); |
| 846 | markNeedsAddToScene(); |
| 847 | _picture?.dispose(); |
| 848 | _picture = picture; |
| 849 | } |
| 850 | |
| 851 | /// Hints that the painting in this layer is complex and would benefit from |
| 852 | /// caching. |
| 853 | /// |
| 854 | /// If this hint is not set, the compositor will apply its own heuristics to |
| 855 | /// decide whether the this layer is complex enough to benefit from caching. |
| 856 | /// |
| 857 | /// The scene must be explicitly recomposited after this property is changed |
| 858 | /// (as described at [Layer]). |
| 859 | bool get isComplexHint => _isComplexHint; |
| 860 | bool _isComplexHint = false; |
| 861 | set isComplexHint(bool value) { |
| 862 | if (value != _isComplexHint) { |
| 863 | _isComplexHint = value; |
| 864 | markNeedsAddToScene(); |
| 865 | } |
| 866 | } |
| 867 | |
| 868 | /// Hints that the painting in this layer is likely to change next frame. |
| 869 | /// |
| 870 | /// This hint tells the compositor not to cache this layer because the cache |
| 871 | /// will not be used in the future. If this hint is not set, the compositor |
| 872 | /// will apply its own heuristics to decide whether this layer is likely to be |
| 873 | /// reused in the future. |
| 874 | /// |
| 875 | /// The scene must be explicitly recomposited after this property is changed |
| 876 | /// (as described at [Layer]). |
| 877 | bool get willChangeHint => _willChangeHint; |
| 878 | bool _willChangeHint = false; |
| 879 | set willChangeHint(bool value) { |
| 880 | if (value != _willChangeHint) { |
| 881 | _willChangeHint = value; |
| 882 | markNeedsAddToScene(); |
| 883 | } |
| 884 | } |
| 885 | |
| 886 | @override |
| 887 | void dispose() { |
| 888 | picture = null; // Will dispose _picture. |
| 889 | super.dispose(); |
| 890 | } |
| 891 | |
| 892 | @override |
| 893 | void addToScene(ui.SceneBuilder builder) { |
| 894 | assert(picture != null); |
| 895 | builder.addPicture( |
| 896 | Offset.zero, |
| 897 | picture!, |
| 898 | isComplexHint: isComplexHint, |
| 899 | willChangeHint: willChangeHint, |
| 900 | ); |
| 901 | } |
| 902 | |
| 903 | @override |
| 904 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 905 | super.debugFillProperties(properties); |
| 906 | properties.add(DiagnosticsProperty<Rect>('paint bounds', canvasBounds)); |
| 907 | properties.add(DiagnosticsProperty<String>('picture', describeIdentity(_picture))); |
| 908 | properties.add( |
| 909 | DiagnosticsProperty<String>( |
| 910 | 'raster cache hints', |
| 911 | 'isComplex =$isComplexHint, willChange =$willChangeHint', |
| 912 | ), |
| 913 | ); |
| 914 | } |
| 915 | |
| 916 | @override |
| 917 | bool findAnnotations<S extends Object>( |
| 918 | AnnotationResult<S> result, |
| 919 | Offset localPosition, { |
| 920 | required bool onlyFirst, |
| 921 | }) { |
| 922 | return false; |
| 923 | } |
| 924 | } |
| 925 | |
| 926 | /// A composited layer that maps a backend texture to a rectangle. |
| 927 | /// |
| 928 | /// Backend textures are images that can be applied (mapped) to an area of the |
| 929 | /// Flutter view. They are created, managed, and updated using a |
| 930 | /// platform-specific texture registry. This is typically done by a plugin |
| 931 | /// that integrates with host platform video player, camera, or OpenGL APIs, |
| 932 | /// or similar image sources. |
| 933 | /// |
| 934 | /// A texture layer refers to its backend texture using an integer ID. Texture |
| 935 | /// IDs are obtained from the texture registry and are scoped to the Flutter |
| 936 | /// view. Texture IDs may be reused after deregistration, at the discretion |
| 937 | /// of the registry. The use of texture IDs currently unknown to the registry |
| 938 | /// will silently result in a blank rectangle. |
| 939 | /// |
| 940 | /// Once inserted into the layer tree, texture layers are repainted autonomously |
| 941 | /// as dictated by the backend (e.g. on arrival of a video frame). Such |
| 942 | /// repainting generally does not involve executing Dart code. |
| 943 | /// |
| 944 | /// Texture layers are always leaves in the layer tree. |
| 945 | /// |
| 946 | /// See also: |
| 947 | /// |
| 948 | /// * [TextureRegistry](/javadoc/io/flutter/view/TextureRegistry.html) |
| 949 | /// for how to create and manage backend textures on Android. |
| 950 | /// * [TextureRegistry Protocol](/ios-embedder/protocol_flutter_texture_registry-p.html) |
| 951 | /// for how to create and manage backend textures on iOS. |
| 952 | class TextureLayer extends Layer { |
| 953 | /// Creates a texture layer bounded by [rect] and with backend texture |
| 954 | /// identified by [textureId], if [freeze] is true new texture frames will not be |
| 955 | /// populated to the texture, and use [filterQuality] to set layer's [FilterQuality]. |
| 956 | TextureLayer({ |
| 957 | required this.rect, |
| 958 | required this.textureId, |
| 959 | this.freeze = false, |
| 960 | this.filterQuality = ui.FilterQuality.low, |
| 961 | }); |
| 962 | |
| 963 | /// Bounding rectangle of this layer. |
| 964 | final Rect rect; |
| 965 | |
| 966 | /// The identity of the backend texture. |
| 967 | final int textureId; |
| 968 | |
| 969 | /// When true the texture will not be updated with new frames. |
| 970 | /// |
| 971 | /// This is used for resizing embedded Android views: when resizing there |
| 972 | /// is a short period during which the framework cannot tell if the newest |
| 973 | /// texture frame has the previous or new size; to work around this, the |
| 974 | /// framework "freezes" the texture just before resizing the Android view and |
| 975 | /// un-freezes it when it is certain that a frame with the new size is ready. |
| 976 | final bool freeze; |
| 977 | |
| 978 | /// {@macro flutter.widgets.Texture.filterQuality} |
| 979 | final ui.FilterQuality filterQuality; |
| 980 | |
| 981 | @override |
| 982 | void addToScene(ui.SceneBuilder builder) { |
| 983 | builder.addTexture( |
| 984 | textureId, |
| 985 | offset: rect.topLeft, |
| 986 | width: rect.width, |
| 987 | height: rect.height, |
| 988 | freeze: freeze, |
| 989 | filterQuality: filterQuality, |
| 990 | ); |
| 991 | } |
| 992 | |
| 993 | @override |
| 994 | bool findAnnotations<S extends Object>( |
| 995 | AnnotationResult<S> result, |
| 996 | Offset localPosition, { |
| 997 | required bool onlyFirst, |
| 998 | }) { |
| 999 | return false; |
| 1000 | } |
| 1001 | } |
| 1002 | |
| 1003 | /// A layer that shows an embedded [UIView](https://developer.apple.com/documentation/uikit/uiview) |
| 1004 | /// on iOS. |
| 1005 | class PlatformViewLayer extends Layer { |
| 1006 | /// Creates a platform view layer. |
| 1007 | PlatformViewLayer({required this.rect, required this.viewId}); |
| 1008 | |
| 1009 | /// Bounding rectangle of this layer in the global coordinate space. |
| 1010 | final Rect rect; |
| 1011 | |
| 1012 | /// The unique identifier of the UIView displayed on this layer. |
| 1013 | /// |
| 1014 | /// A UIView with this identifier must have been created by [PlatformViewsService.initUiKitView]. |
| 1015 | final int viewId; |
| 1016 | |
| 1017 | @override |
| 1018 | bool supportsRasterization() { |
| 1019 | return false; |
| 1020 | } |
| 1021 | |
| 1022 | @override |
| 1023 | void addToScene(ui.SceneBuilder builder) { |
| 1024 | builder.addPlatformView(viewId, offset: rect.topLeft, width: rect.width, height: rect.height); |
| 1025 | } |
| 1026 | } |
| 1027 | |
| 1028 | /// A layer that indicates to the compositor that it should display |
| 1029 | /// certain performance statistics within it. |
| 1030 | /// |
| 1031 | /// Performance overlay layers are always leaves in the layer tree. |
| 1032 | class PerformanceOverlayLayer extends Layer { |
| 1033 | /// Creates a layer that displays a performance overlay. |
| 1034 | PerformanceOverlayLayer({required Rect overlayRect, required this.optionsMask}) |
| 1035 | : _overlayRect = overlayRect; |
| 1036 | |
| 1037 | /// The rectangle in this layer's coordinate system that the overlay should occupy. |
| 1038 | /// |
| 1039 | /// The scene must be explicitly recomposited after this property is changed |
| 1040 | /// (as described at [Layer]). |
| 1041 | Rect get overlayRect => _overlayRect; |
| 1042 | Rect _overlayRect; |
| 1043 | set overlayRect(Rect value) { |
| 1044 | if (value != _overlayRect) { |
| 1045 | _overlayRect = value; |
| 1046 | markNeedsAddToScene(); |
| 1047 | } |
| 1048 | } |
| 1049 | |
| 1050 | /// The mask is created by shifting 1 by the index of the specific |
| 1051 | /// [PerformanceOverlayOption] to enable. |
| 1052 | final int optionsMask; |
| 1053 | |
| 1054 | @override |
| 1055 | void addToScene(ui.SceneBuilder builder) { |
| 1056 | builder.addPerformanceOverlay(optionsMask, overlayRect); |
| 1057 | } |
| 1058 | |
| 1059 | @override |
| 1060 | bool findAnnotations<S extends Object>( |
| 1061 | AnnotationResult<S> result, |
| 1062 | Offset localPosition, { |
| 1063 | required bool onlyFirst, |
| 1064 | }) { |
| 1065 | return false; |
| 1066 | } |
| 1067 | } |
| 1068 | |
| 1069 | /// The signature of the callback added in [Layer.addCompositionCallback]. |
| 1070 | typedef CompositionCallback = void Function(Layer layer); |
| 1071 | |
| 1072 | /// A composited layer that has a list of children. |
| 1073 | /// |
| 1074 | /// A [ContainerLayer] instance merely takes a list of children and inserts them |
| 1075 | /// into the composited rendering in order. There are subclasses of |
| 1076 | /// [ContainerLayer] which apply more elaborate effects in the process. |
| 1077 | class ContainerLayer extends Layer { |
| 1078 | @override |
| 1079 | void _fireCompositionCallbacks({required bool includeChildren}) { |
| 1080 | super._fireCompositionCallbacks(includeChildren: includeChildren); |
| 1081 | if (!includeChildren) { |
| 1082 | return; |
| 1083 | } |
| 1084 | Layer? child = firstChild; |
| 1085 | while (child != null) { |
| 1086 | child._fireCompositionCallbacks(includeChildren: includeChildren); |
| 1087 | child = child.nextSibling; |
| 1088 | } |
| 1089 | } |
| 1090 | |
| 1091 | /// The first composited layer in this layer's child list. |
| 1092 | Layer? get firstChild => _firstChild; |
| 1093 | Layer? _firstChild; |
| 1094 | |
| 1095 | /// The last composited layer in this layer's child list. |
| 1096 | Layer? get lastChild => _lastChild; |
| 1097 | Layer? _lastChild; |
| 1098 | |
| 1099 | /// Returns whether this layer has at least one child layer. |
| 1100 | bool get hasChildren => _firstChild != null; |
| 1101 | |
| 1102 | @override |
| 1103 | bool supportsRasterization() { |
| 1104 | for (Layer? child = lastChild; child != null; child = child.previousSibling) { |
| 1105 | if (!child.supportsRasterization()) { |
| 1106 | return false; |
| 1107 | } |
| 1108 | } |
| 1109 | return true; |
| 1110 | } |
| 1111 | |
| 1112 | /// Consider this layer as the root and build a scene (a tree of layers) |
| 1113 | /// in the engine. |
| 1114 | // The reason this method is in the `ContainerLayer` class rather than |
| 1115 | // `PipelineOwner` or other singleton level is because this method can be used |
| 1116 | // both to render the whole layer tree (e.g. a normal application frame) and |
| 1117 | // to render a subtree (e.g. `OffsetLayer.toImage`). |
| 1118 | ui.Scene buildScene(ui.SceneBuilder builder) { |
| 1119 | updateSubtreeNeedsAddToScene(); |
| 1120 | addToScene(builder); |
| 1121 | if (subtreeHasCompositionCallbacks) { |
| 1122 | _fireCompositionCallbacks(includeChildren: true); |
| 1123 | } |
| 1124 | // Clearing the flag _after_ calling `addToScene`, not _before_. This is |
| 1125 | // because `addToScene` calls children's `addToScene` methods, which may |
| 1126 | // mark this layer as dirty. |
| 1127 | _needsAddToScene = false; |
| 1128 | final ui.Scene scene = builder.build(); |
| 1129 | return scene; |
| 1130 | } |
| 1131 | |
| 1132 | bool _debugUltimatePreviousSiblingOf(Layer child, {Layer? equals}) { |
| 1133 | assert(child.attached == attached); |
| 1134 | while (child.previousSibling != null) { |
| 1135 | assert(child.previousSibling != child); |
| 1136 | child = child.previousSibling!; |
| 1137 | assert(child.attached == attached); |
| 1138 | } |
| 1139 | return child == equals; |
| 1140 | } |
| 1141 | |
| 1142 | bool _debugUltimateNextSiblingOf(Layer child, {Layer? equals}) { |
| 1143 | assert(child.attached == attached); |
| 1144 | while (child._nextSibling != null) { |
| 1145 | assert(child._nextSibling != child); |
| 1146 | child = child._nextSibling!; |
| 1147 | assert(child.attached == attached); |
| 1148 | } |
| 1149 | return child == equals; |
| 1150 | } |
| 1151 | |
| 1152 | @override |
| 1153 | void dispose() { |
| 1154 | removeAllChildren(); |
| 1155 | _callbacks.clear(); |
| 1156 | super.dispose(); |
| 1157 | } |
| 1158 | |
| 1159 | @override |
| 1160 | void updateSubtreeNeedsAddToScene() { |
| 1161 | super.updateSubtreeNeedsAddToScene(); |
| 1162 | Layer? child = firstChild; |
| 1163 | while (child != null) { |
| 1164 | child.updateSubtreeNeedsAddToScene(); |
| 1165 | _needsAddToScene = _needsAddToScene || child._needsAddToScene; |
| 1166 | child = child.nextSibling; |
| 1167 | } |
| 1168 | } |
| 1169 | |
| 1170 | @override |
| 1171 | bool findAnnotations<S extends Object>( |
| 1172 | AnnotationResult<S> result, |
| 1173 | Offset localPosition, { |
| 1174 | required bool onlyFirst, |
| 1175 | }) { |
| 1176 | for (Layer? child = lastChild; child != null; child = child.previousSibling) { |
| 1177 | final bool isAbsorbed = child.findAnnotations<S>(result, localPosition, onlyFirst: onlyFirst); |
| 1178 | if (isAbsorbed) { |
| 1179 | return true; |
| 1180 | } |
| 1181 | if (onlyFirst && result.entries.isNotEmpty) { |
| 1182 | return isAbsorbed; |
| 1183 | } |
| 1184 | } |
| 1185 | return false; |
| 1186 | } |
| 1187 | |
| 1188 | @override |
| 1189 | void attach(Object owner) { |
| 1190 | assert(!_debugMutationsLocked); |
| 1191 | super.attach(owner); |
| 1192 | Layer? child = firstChild; |
| 1193 | while (child != null) { |
| 1194 | child.attach(owner); |
| 1195 | child = child.nextSibling; |
| 1196 | } |
| 1197 | } |
| 1198 | |
| 1199 | @override |
| 1200 | void detach() { |
| 1201 | assert(!_debugMutationsLocked); |
| 1202 | super.detach(); |
| 1203 | Layer? child = firstChild; |
| 1204 | while (child != null) { |
| 1205 | child.detach(); |
| 1206 | child = child.nextSibling; |
| 1207 | } |
| 1208 | // Detach indicates that we may never be composited again. Clients |
| 1209 | // interested in observing composition need to get an update here because |
| 1210 | // they might otherwise never get another one even though the layer is no |
| 1211 | // longer visible. |
| 1212 | // |
| 1213 | // Children fired them already in child.detach(). |
| 1214 | _fireCompositionCallbacks(includeChildren: false); |
| 1215 | } |
| 1216 | |
| 1217 | /// Adds the given layer to the end of this layer's child list. |
| 1218 | void append(Layer child) { |
| 1219 | assert(!_debugMutationsLocked); |
| 1220 | assert(child != this); |
| 1221 | assert(child != firstChild); |
| 1222 | assert(child != lastChild); |
| 1223 | assert(child.parent == null); |
| 1224 | assert(!child.attached); |
| 1225 | assert(child.nextSibling == null); |
| 1226 | assert(child.previousSibling == null); |
| 1227 | assert(child._parentHandle.layer == null); |
| 1228 | assert(() { |
| 1229 | Layer node = this; |
| 1230 | while (node.parent != null) { |
| 1231 | node = node.parent!; |
| 1232 | } |
| 1233 | assert(node != child); // indicates we are about to create a cycle |
| 1234 | return true; |
| 1235 | }()); |
| 1236 | _adoptChild(child); |
| 1237 | child._previousSibling = lastChild; |
| 1238 | if (lastChild != null) { |
| 1239 | lastChild!._nextSibling = child; |
| 1240 | } |
| 1241 | _lastChild = child; |
| 1242 | _firstChild ??= child; |
| 1243 | child._parentHandle.layer = child; |
| 1244 | assert(child.attached == attached); |
| 1245 | } |
| 1246 | |
| 1247 | void _adoptChild(Layer child) { |
| 1248 | assert(!_debugMutationsLocked); |
| 1249 | if (!alwaysNeedsAddToScene) { |
| 1250 | markNeedsAddToScene(); |
| 1251 | } |
| 1252 | if (child._compositionCallbackCount != 0) { |
| 1253 | _updateSubtreeCompositionObserverCount(child._compositionCallbackCount); |
| 1254 | } |
| 1255 | assert(child._parent == null); |
| 1256 | assert(() { |
| 1257 | Layer node = this; |
| 1258 | while (node.parent != null) { |
| 1259 | node = node.parent!; |
| 1260 | } |
| 1261 | assert(node != child); // indicates we are about to create a cycle |
| 1262 | return true; |
| 1263 | }()); |
| 1264 | child._parent = this; |
| 1265 | if (attached) { |
| 1266 | child.attach(_owner!); |
| 1267 | } |
| 1268 | redepthChild(child); |
| 1269 | } |
| 1270 | |
| 1271 | @override |
| 1272 | void redepthChildren() { |
| 1273 | Layer? child = firstChild; |
| 1274 | while (child != null) { |
| 1275 | redepthChild(child); |
| 1276 | child = child.nextSibling; |
| 1277 | } |
| 1278 | } |
| 1279 | |
| 1280 | /// Adjust the [depth] of the given [child] to be greater than this node's own |
| 1281 | /// [depth]. |
| 1282 | /// |
| 1283 | /// Only call this method from overrides of [redepthChildren]. |
| 1284 | @protected |
| 1285 | void redepthChild(Layer child) { |
| 1286 | assert(child.owner == owner); |
| 1287 | if (child._depth <= _depth) { |
| 1288 | child._depth = _depth + 1; |
| 1289 | child.redepthChildren(); |
| 1290 | } |
| 1291 | } |
| 1292 | |
| 1293 | // Implementation of [Layer.remove]. |
| 1294 | void _removeChild(Layer child) { |
| 1295 | assert(child.parent == this); |
| 1296 | assert(child.attached == attached); |
| 1297 | assert(_debugUltimatePreviousSiblingOf(child, equals: firstChild)); |
| 1298 | assert(_debugUltimateNextSiblingOf(child, equals: lastChild)); |
| 1299 | assert(child._parentHandle.layer != null); |
| 1300 | if (child._previousSibling == null) { |
| 1301 | assert(_firstChild == child); |
| 1302 | _firstChild = child._nextSibling; |
| 1303 | } else { |
| 1304 | child._previousSibling!._nextSibling = child.nextSibling; |
| 1305 | } |
| 1306 | if (child._nextSibling == null) { |
| 1307 | assert(lastChild == child); |
| 1308 | _lastChild = child.previousSibling; |
| 1309 | } else { |
| 1310 | child.nextSibling!._previousSibling = child.previousSibling; |
| 1311 | } |
| 1312 | assert((firstChild == null) == (lastChild == null)); |
| 1313 | assert(firstChild == null || firstChild!.attached == attached); |
| 1314 | assert(lastChild == null || lastChild!.attached == attached); |
| 1315 | assert(firstChild == null || _debugUltimateNextSiblingOf(firstChild!, equals: lastChild)); |
| 1316 | assert(lastChild == null || _debugUltimatePreviousSiblingOf(lastChild!, equals: firstChild)); |
| 1317 | child._previousSibling = null; |
| 1318 | child._nextSibling = null; |
| 1319 | _dropChild(child); |
| 1320 | child._parentHandle.layer = null; |
| 1321 | assert(!child.attached); |
| 1322 | } |
| 1323 | |
| 1324 | void _dropChild(Layer child) { |
| 1325 | assert(!_debugMutationsLocked); |
| 1326 | if (!alwaysNeedsAddToScene) { |
| 1327 | markNeedsAddToScene(); |
| 1328 | } |
| 1329 | if (child._compositionCallbackCount != 0) { |
| 1330 | _updateSubtreeCompositionObserverCount(-child._compositionCallbackCount); |
| 1331 | } |
| 1332 | assert(child._parent == this); |
| 1333 | assert(child.attached == attached); |
| 1334 | child._parent = null; |
| 1335 | if (attached) { |
| 1336 | child.detach(); |
| 1337 | } |
| 1338 | } |
| 1339 | |
| 1340 | /// Removes all of this layer's children from its child list. |
| 1341 | void removeAllChildren() { |
| 1342 | assert(!_debugMutationsLocked); |
| 1343 | Layer? child = firstChild; |
| 1344 | while (child != null) { |
| 1345 | final Layer? next = child.nextSibling; |
| 1346 | child._previousSibling = null; |
| 1347 | child._nextSibling = null; |
| 1348 | assert(child.attached == attached); |
| 1349 | _dropChild(child); |
| 1350 | child._parentHandle.layer = null; |
| 1351 | child = next; |
| 1352 | } |
| 1353 | _firstChild = null; |
| 1354 | _lastChild = null; |
| 1355 | } |
| 1356 | |
| 1357 | @override |
| 1358 | void addToScene(ui.SceneBuilder builder) { |
| 1359 | addChildrenToScene(builder); |
| 1360 | } |
| 1361 | |
| 1362 | /// Uploads all of this layer's children to the engine. |
| 1363 | /// |
| 1364 | /// This method is typically used by [addToScene] to insert the children into |
| 1365 | /// the scene. Subclasses of [ContainerLayer] typically override [addToScene] |
| 1366 | /// to apply effects to the scene using the [ui.SceneBuilder] API, then insert |
| 1367 | /// their children using [addChildrenToScene], then reverse the aforementioned |
| 1368 | /// effects before returning from [addToScene]. |
| 1369 | void addChildrenToScene(ui.SceneBuilder builder) { |
| 1370 | Layer? child = firstChild; |
| 1371 | while (child != null) { |
| 1372 | child._addToSceneWithRetainedRendering(builder); |
| 1373 | child = child.nextSibling; |
| 1374 | } |
| 1375 | } |
| 1376 | |
| 1377 | /// Applies the transform that would be applied when compositing the given |
| 1378 | /// child to the given matrix. |
| 1379 | /// |
| 1380 | /// Specifically, this should apply the transform that is applied to child's |
| 1381 | /// _origin_. When using [applyTransform] with a chain of layers, results will |
| 1382 | /// be unreliable unless the deepest layer in the chain collapses the |
| 1383 | /// `layerOffset` in [addToScene] to zero, meaning that it passes |
| 1384 | /// [Offset.zero] to its children, and bakes any incoming `layerOffset` into |
| 1385 | /// the [ui.SceneBuilder] as (for instance) a transform (which is then also |
| 1386 | /// included in the transformation applied by [applyTransform]). |
| 1387 | /// |
| 1388 | /// For example, if [addToScene] applies the `layerOffset` and then |
| 1389 | /// passes [Offset.zero] to the children, then it should be included in the |
| 1390 | /// transform applied here, whereas if [addToScene] just passes the |
| 1391 | /// `layerOffset` to the child, then it should not be included in the |
| 1392 | /// transform applied here. |
| 1393 | /// |
| 1394 | /// This method is only valid immediately after [addToScene] has been called, |
| 1395 | /// before any of the properties have been changed. |
| 1396 | /// |
| 1397 | /// The default implementation does nothing, since [ContainerLayer], by |
| 1398 | /// default, composites its children at the origin of the [ContainerLayer] |
| 1399 | /// itself. |
| 1400 | /// |
| 1401 | /// The `child` argument should generally not be null, since in principle a |
| 1402 | /// layer could transform each child independently. However, certain layers |
| 1403 | /// may explicitly allow null as a value, for example if they know that they |
| 1404 | /// transform all their children identically. |
| 1405 | /// |
| 1406 | /// Used by [FollowerLayer] to transform its child to a [LeaderLayer]'s |
| 1407 | /// position. |
| 1408 | void applyTransform(Layer? child, Matrix4 transform) { |
| 1409 | assert(child != null); |
| 1410 | } |
| 1411 | |
| 1412 | /// Returns the descendants of this layer in depth first order. |
| 1413 | @visibleForTesting |
| 1414 | List<Layer> depthFirstIterateChildren() { |
| 1415 | if (firstChild == null) { |
| 1416 | return <Layer>[]; |
| 1417 | } |
| 1418 | final List<Layer> children = <Layer>[]; |
| 1419 | Layer? child = firstChild; |
| 1420 | while (child != null) { |
| 1421 | children.add(child); |
| 1422 | if (child is ContainerLayer) { |
| 1423 | children.addAll(child.depthFirstIterateChildren()); |
| 1424 | } |
| 1425 | child = child.nextSibling; |
| 1426 | } |
| 1427 | return children; |
| 1428 | } |
| 1429 | |
| 1430 | @override |
| 1431 | List<DiagnosticsNode> debugDescribeChildren() { |
| 1432 | final List<DiagnosticsNode> children = <DiagnosticsNode>[]; |
| 1433 | if (firstChild == null) { |
| 1434 | return children; |
| 1435 | } |
| 1436 | Layer? child = firstChild; |
| 1437 | int count = 1; |
| 1438 | while (true) { |
| 1439 | children.add(child!.toDiagnosticsNode(name:'child$count')); |
| 1440 | if (child == lastChild) { |
| 1441 | break; |
| 1442 | } |
| 1443 | count += 1; |
| 1444 | child = child.nextSibling; |
| 1445 | } |
| 1446 | return children; |
| 1447 | } |
| 1448 | } |
| 1449 | |
| 1450 | /// A layer that is displayed at an offset from its parent layer. |
| 1451 | /// |
| 1452 | /// Offset layers are key to efficient repainting because they are created by |
| 1453 | /// repaint boundaries in the [RenderObject] tree (see |
| 1454 | /// [RenderObject.isRepaintBoundary]). When a render object that is a repaint |
| 1455 | /// boundary is asked to paint at given offset in a [PaintingContext], the |
| 1456 | /// render object first checks whether it needs to repaint itself. If not, it |
| 1457 | /// reuses its existing [OffsetLayer] (and its entire subtree) by mutating its |
| 1458 | /// [offset] property, cutting off the paint walk. |
| 1459 | class OffsetLayer extends ContainerLayer { |
| 1460 | /// Creates an offset layer. |
| 1461 | /// |
| 1462 | /// By default, [offset] is zero. It must be non-null before the compositing |
| 1463 | /// phase of the pipeline. |
| 1464 | OffsetLayer({Offset offset = Offset.zero}) : _offset = offset; |
| 1465 | |
| 1466 | /// Offset from parent in the parent's coordinate system. |
| 1467 | /// |
| 1468 | /// The scene must be explicitly recomposited after this property is changed |
| 1469 | /// (as described at [Layer]). |
| 1470 | /// |
| 1471 | /// The [offset] property must be non-null before the compositing phase of the |
| 1472 | /// pipeline. |
| 1473 | Offset get offset => _offset; |
| 1474 | Offset _offset; |
| 1475 | set offset(Offset value) { |
| 1476 | if (value != _offset) { |
| 1477 | markNeedsAddToScene(); |
| 1478 | } |
| 1479 | _offset = value; |
| 1480 | } |
| 1481 | |
| 1482 | @override |
| 1483 | bool findAnnotations<S extends Object>( |
| 1484 | AnnotationResult<S> result, |
| 1485 | Offset localPosition, { |
| 1486 | required bool onlyFirst, |
| 1487 | }) { |
| 1488 | return super.findAnnotations<S>(result, localPosition - offset, onlyFirst: onlyFirst); |
| 1489 | } |
| 1490 | |
| 1491 | @override |
| 1492 | void applyTransform(Layer? child, Matrix4 transform) { |
| 1493 | assert(child != null); |
| 1494 | transform.translate(offset.dx, offset.dy); |
| 1495 | } |
| 1496 | |
| 1497 | @override |
| 1498 | void addToScene(ui.SceneBuilder builder) { |
| 1499 | // Skia has a fast path for concatenating scale/translation only matrices. |
| 1500 | // Hence pushing a translation-only transform layer should be fast. For |
| 1501 | // retained rendering, we don't want to push the offset down to each leaf |
| 1502 | // node. Otherwise, changing an offset layer on the very high level could |
| 1503 | // cascade the change to too many leaves. |
| 1504 | engineLayer = builder.pushOffset( |
| 1505 | offset.dx, |
| 1506 | offset.dy, |
| 1507 | oldLayer: _engineLayer as ui.OffsetEngineLayer?, |
| 1508 | ); |
| 1509 | addChildrenToScene(builder); |
| 1510 | builder.pop(); |
| 1511 | } |
| 1512 | |
| 1513 | @override |
| 1514 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1515 | super.debugFillProperties(properties); |
| 1516 | properties.add(DiagnosticsProperty<Offset>('offset', offset)); |
| 1517 | } |
| 1518 | |
| 1519 | ui.Scene _createSceneForImage(Rect bounds, {double pixelRatio = 1.0}) { |
| 1520 | final ui.SceneBuilder builder = ui.SceneBuilder(); |
| 1521 | final Matrix4 transform = Matrix4.diagonal3Values(pixelRatio, pixelRatio, 1); |
| 1522 | transform.translate(-(bounds.left + offset.dx), -(bounds.top + offset.dy)); |
| 1523 | builder.pushTransform(transform.storage); |
| 1524 | return buildScene(builder); |
| 1525 | } |
| 1526 | |
| 1527 | /// Capture an image of the current state of this layer and its children. |
| 1528 | /// |
| 1529 | /// The returned [ui.Image] has uncompressed raw RGBA bytes, will be offset |
| 1530 | /// by the top-left corner of [bounds], and have dimensions equal to the size |
| 1531 | /// of [bounds] multiplied by [pixelRatio]. |
| 1532 | /// |
| 1533 | /// The [pixelRatio] describes the scale between the logical pixels and the |
| 1534 | /// size of the output image. It is independent of the |
| 1535 | /// [dart:ui.FlutterView.devicePixelRatio] for the device, so specifying 1.0 |
| 1536 | /// (the default) will give you a 1:1 mapping between logical pixels and the |
| 1537 | /// output pixels in the image. |
| 1538 | /// |
| 1539 | /// This API functions like [toImageSync], except that it only returns after |
| 1540 | /// rasterization is complete. |
| 1541 | /// |
| 1542 | /// See also: |
| 1543 | /// |
| 1544 | /// * [RenderRepaintBoundary.toImage] for a similar API at the render object level. |
| 1545 | /// * [dart:ui.Scene.toImage] for more information about the image returned. |
| 1546 | Future<ui.Image> toImage(Rect bounds, {double pixelRatio = 1.0}) async { |
| 1547 | final ui.Scene scene = _createSceneForImage(bounds, pixelRatio: pixelRatio); |
| 1548 | |
| 1549 | try { |
| 1550 | // Size is rounded up to the next pixel to make sure we don't clip off |
| 1551 | // anything. |
| 1552 | return await scene.toImage( |
| 1553 | (pixelRatio * bounds.width).ceil(), |
| 1554 | (pixelRatio * bounds.height).ceil(), |
| 1555 | ); |
| 1556 | } finally { |
| 1557 | scene.dispose(); |
| 1558 | } |
| 1559 | } |
| 1560 | |
| 1561 | /// Capture an image of the current state of this layer and its children. |
| 1562 | /// |
| 1563 | /// The returned [ui.Image] has uncompressed raw RGBA bytes, will be offset |
| 1564 | /// by the top-left corner of [bounds], and have dimensions equal to the size |
| 1565 | /// of [bounds] multiplied by [pixelRatio]. |
| 1566 | /// |
| 1567 | /// The [pixelRatio] describes the scale between the logical pixels and the |
| 1568 | /// size of the output image. It is independent of the |
| 1569 | /// [dart:ui.FlutterView.devicePixelRatio] for the device, so specifying 1.0 |
| 1570 | /// (the default) will give you a 1:1 mapping between logical pixels and the |
| 1571 | /// output pixels in the image. |
| 1572 | /// |
| 1573 | /// This API functions like [toImage], except that rasterization begins eagerly |
| 1574 | /// on the raster thread and the image is returned before this is completed. |
| 1575 | /// |
| 1576 | /// See also: |
| 1577 | /// |
| 1578 | /// * [RenderRepaintBoundary.toImage] for a similar API at the render object level. |
| 1579 | /// * [dart:ui.Scene.toImage] for more information about the image returned. |
| 1580 | ui.Image toImageSync(Rect bounds, {double pixelRatio = 1.0}) { |
| 1581 | final ui.Scene scene = _createSceneForImage(bounds, pixelRatio: pixelRatio); |
| 1582 | |
| 1583 | try { |
| 1584 | // Size is rounded up to the next pixel to make sure we don't clip off |
| 1585 | // anything. |
| 1586 | return scene.toImageSync( |
| 1587 | (pixelRatio * bounds.width).ceil(), |
| 1588 | (pixelRatio * bounds.height).ceil(), |
| 1589 | ); |
| 1590 | } finally { |
| 1591 | scene.dispose(); |
| 1592 | } |
| 1593 | } |
| 1594 | } |
| 1595 | |
| 1596 | /// A composite layer that clips its children using a rectangle. |
| 1597 | /// |
| 1598 | /// When debugging, setting [debugDisableClipLayers] to true will cause this |
| 1599 | /// layer to be skipped (directly replaced by its children). This can be helpful |
| 1600 | /// to track down the cause of performance problems. |
| 1601 | class ClipRectLayer extends ContainerLayer { |
| 1602 | /// Creates a layer with a rectangular clip. |
| 1603 | /// |
| 1604 | /// The [clipRect] argument must not be null before the compositing phase of |
| 1605 | /// the pipeline. |
| 1606 | /// |
| 1607 | /// The [clipBehavior] argument must not be [Clip.none]. |
| 1608 | ClipRectLayer({Rect? clipRect, Clip clipBehavior = Clip.hardEdge}) |
| 1609 | : _clipRect = clipRect, |
| 1610 | _clipBehavior = clipBehavior, |
| 1611 | assert(clipBehavior != Clip.none); |
| 1612 | |
| 1613 | /// The rectangle to clip in the parent's coordinate system. |
| 1614 | /// |
| 1615 | /// The scene must be explicitly recomposited after this property is changed |
| 1616 | /// (as described at [Layer]). |
| 1617 | Rect? get clipRect => _clipRect; |
| 1618 | Rect? _clipRect; |
| 1619 | set clipRect(Rect? value) { |
| 1620 | if (value != _clipRect) { |
| 1621 | _clipRect = value; |
| 1622 | markNeedsAddToScene(); |
| 1623 | } |
| 1624 | } |
| 1625 | |
| 1626 | @override |
| 1627 | Rect? describeClipBounds() => clipRect; |
| 1628 | |
| 1629 | /// {@template flutter.rendering.ClipRectLayer.clipBehavior} |
| 1630 | /// Controls how to clip. |
| 1631 | /// |
| 1632 | /// Must not be set to null or [Clip.none]. |
| 1633 | /// {@endtemplate} |
| 1634 | /// |
| 1635 | /// Defaults to [Clip.hardEdge]. |
| 1636 | Clip get clipBehavior => _clipBehavior; |
| 1637 | Clip _clipBehavior; |
| 1638 | set clipBehavior(Clip value) { |
| 1639 | assert(value != Clip.none); |
| 1640 | if (value != _clipBehavior) { |
| 1641 | _clipBehavior = value; |
| 1642 | markNeedsAddToScene(); |
| 1643 | } |
| 1644 | } |
| 1645 | |
| 1646 | @override |
| 1647 | bool findAnnotations<S extends Object>( |
| 1648 | AnnotationResult<S> result, |
| 1649 | Offset localPosition, { |
| 1650 | required bool onlyFirst, |
| 1651 | }) { |
| 1652 | if (!clipRect!.contains(localPosition)) { |
| 1653 | return false; |
| 1654 | } |
| 1655 | return super.findAnnotations<S>(result, localPosition, onlyFirst: onlyFirst); |
| 1656 | } |
| 1657 | |
| 1658 | @override |
| 1659 | void addToScene(ui.SceneBuilder builder) { |
| 1660 | assert(clipRect != null); |
| 1661 | bool enabled = true; |
| 1662 | assert(() { |
| 1663 | enabled = !debugDisableClipLayers; |
| 1664 | return true; |
| 1665 | }()); |
| 1666 | if (enabled) { |
| 1667 | engineLayer = builder.pushClipRect( |
| 1668 | clipRect!, |
| 1669 | clipBehavior: clipBehavior, |
| 1670 | oldLayer: _engineLayer as ui.ClipRectEngineLayer?, |
| 1671 | ); |
| 1672 | } else { |
| 1673 | engineLayer = null; |
| 1674 | } |
| 1675 | addChildrenToScene(builder); |
| 1676 | if (enabled) { |
| 1677 | builder.pop(); |
| 1678 | } |
| 1679 | } |
| 1680 | |
| 1681 | @override |
| 1682 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1683 | super.debugFillProperties(properties); |
| 1684 | properties.add(DiagnosticsProperty<Rect>('clipRect', clipRect)); |
| 1685 | properties.add(DiagnosticsProperty<Clip>('clipBehavior', clipBehavior)); |
| 1686 | } |
| 1687 | } |
| 1688 | |
| 1689 | /// A composite layer that clips its children using a rounded rectangle. |
| 1690 | /// |
| 1691 | /// When debugging, setting [debugDisableClipLayers] to true will cause this |
| 1692 | /// layer to be skipped (directly replaced by its children). This can be helpful |
| 1693 | /// to track down the cause of performance problems. |
| 1694 | class ClipRRectLayer extends ContainerLayer { |
| 1695 | /// Creates a layer with a rounded-rectangular clip. |
| 1696 | /// |
| 1697 | /// The [clipRRect] and [clipBehavior] properties must be non-null before the |
| 1698 | /// compositing phase of the pipeline. |
| 1699 | ClipRRectLayer({RRect? clipRRect, Clip clipBehavior = Clip.antiAlias}) |
| 1700 | : _clipRRect = clipRRect, |
| 1701 | _clipBehavior = clipBehavior, |
| 1702 | assert(clipBehavior != Clip.none); |
| 1703 | |
| 1704 | /// The rounded-rect to clip in the parent's coordinate system. |
| 1705 | /// |
| 1706 | /// The scene must be explicitly recomposited after this property is changed |
| 1707 | /// (as described at [Layer]). |
| 1708 | RRect? get clipRRect => _clipRRect; |
| 1709 | RRect? _clipRRect; |
| 1710 | set clipRRect(RRect? value) { |
| 1711 | if (value != _clipRRect) { |
| 1712 | _clipRRect = value; |
| 1713 | markNeedsAddToScene(); |
| 1714 | } |
| 1715 | } |
| 1716 | |
| 1717 | @override |
| 1718 | Rect? describeClipBounds() => clipRRect?.outerRect; |
| 1719 | |
| 1720 | /// {@macro flutter.rendering.ClipRectLayer.clipBehavior} |
| 1721 | /// |
| 1722 | /// Defaults to [Clip.antiAlias]. |
| 1723 | Clip get clipBehavior => _clipBehavior; |
| 1724 | Clip _clipBehavior; |
| 1725 | set clipBehavior(Clip value) { |
| 1726 | assert(value != Clip.none); |
| 1727 | if (value != _clipBehavior) { |
| 1728 | _clipBehavior = value; |
| 1729 | markNeedsAddToScene(); |
| 1730 | } |
| 1731 | } |
| 1732 | |
| 1733 | @override |
| 1734 | bool findAnnotations<S extends Object>( |
| 1735 | AnnotationResult<S> result, |
| 1736 | Offset localPosition, { |
| 1737 | required bool onlyFirst, |
| 1738 | }) { |
| 1739 | if (!clipRRect!.contains(localPosition)) { |
| 1740 | return false; |
| 1741 | } |
| 1742 | return super.findAnnotations<S>(result, localPosition, onlyFirst: onlyFirst); |
| 1743 | } |
| 1744 | |
| 1745 | @override |
| 1746 | void addToScene(ui.SceneBuilder builder) { |
| 1747 | assert(clipRRect != null); |
| 1748 | bool enabled = true; |
| 1749 | assert(() { |
| 1750 | enabled = !debugDisableClipLayers; |
| 1751 | return true; |
| 1752 | }()); |
| 1753 | if (enabled) { |
| 1754 | engineLayer = builder.pushClipRRect( |
| 1755 | clipRRect!, |
| 1756 | clipBehavior: clipBehavior, |
| 1757 | oldLayer: _engineLayer as ui.ClipRRectEngineLayer?, |
| 1758 | ); |
| 1759 | } else { |
| 1760 | engineLayer = null; |
| 1761 | } |
| 1762 | addChildrenToScene(builder); |
| 1763 | if (enabled) { |
| 1764 | builder.pop(); |
| 1765 | } |
| 1766 | } |
| 1767 | |
| 1768 | @override |
| 1769 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1770 | super.debugFillProperties(properties); |
| 1771 | properties.add(DiagnosticsProperty<RRect>('clipRRect', clipRRect)); |
| 1772 | properties.add(DiagnosticsProperty<Clip>('clipBehavior', clipBehavior)); |
| 1773 | } |
| 1774 | } |
| 1775 | |
| 1776 | /// A composite layer that clips its children using a rounded superellipse. |
| 1777 | /// |
| 1778 | /// When debugging, setting [debugDisableClipLayers] to true will cause this |
| 1779 | /// layer to be skipped (directly replaced by its children). This can be helpful |
| 1780 | /// to track down the cause of performance problems. |
| 1781 | /// |
| 1782 | /// Hit tests are performed based on the bounding box of the rounded |
| 1783 | /// superellipse. |
| 1784 | class ClipRSuperellipseLayer extends ContainerLayer { |
| 1785 | /// Creates a layer with a rounded-rectangular clip. |
| 1786 | /// |
| 1787 | /// The [clipRSuperellipse] and [clipBehavior] properties must be non-null before the |
| 1788 | /// compositing phase of the pipeline. |
| 1789 | ClipRSuperellipseLayer({RSuperellipse? clipRSuperellipse, Clip clipBehavior = Clip.antiAlias}) |
| 1790 | : _clipRSuperellipse = clipRSuperellipse, |
| 1791 | _clipBehavior = clipBehavior, |
| 1792 | assert(clipBehavior != Clip.none); |
| 1793 | |
| 1794 | /// The rounded-rect to clip in the parent's coordinate system. |
| 1795 | /// |
| 1796 | /// The scene must be explicitly recomposited after this property is changed |
| 1797 | /// (as described at [Layer]). |
| 1798 | RSuperellipse? get clipRSuperellipse => _clipRSuperellipse; |
| 1799 | RSuperellipse? _clipRSuperellipse; |
| 1800 | set clipRSuperellipse(RSuperellipse? value) { |
| 1801 | if (value != _clipRSuperellipse) { |
| 1802 | _clipRSuperellipse = value; |
| 1803 | markNeedsAddToScene(); |
| 1804 | } |
| 1805 | } |
| 1806 | |
| 1807 | @override |
| 1808 | Rect? describeClipBounds() => clipRSuperellipse?.outerRect; |
| 1809 | |
| 1810 | /// {@macro flutter.rendering.ClipRectLayer.clipBehavior} |
| 1811 | /// |
| 1812 | /// Defaults to [Clip.antiAlias]. |
| 1813 | Clip get clipBehavior => _clipBehavior; |
| 1814 | Clip _clipBehavior; |
| 1815 | set clipBehavior(Clip value) { |
| 1816 | assert(value != Clip.none); |
| 1817 | if (value != _clipBehavior) { |
| 1818 | _clipBehavior = value; |
| 1819 | markNeedsAddToScene(); |
| 1820 | } |
| 1821 | } |
| 1822 | |
| 1823 | @override |
| 1824 | bool findAnnotations<S extends Object>( |
| 1825 | AnnotationResult<S> result, |
| 1826 | Offset localPosition, { |
| 1827 | required bool onlyFirst, |
| 1828 | }) { |
| 1829 | if (!clipRSuperellipse!.outerRect.contains(localPosition)) { |
| 1830 | return false; |
| 1831 | } |
| 1832 | return super.findAnnotations<S>(result, localPosition, onlyFirst: onlyFirst); |
| 1833 | } |
| 1834 | |
| 1835 | @override |
| 1836 | void addToScene(ui.SceneBuilder builder) { |
| 1837 | assert(clipRSuperellipse != null); |
| 1838 | bool enabled = true; |
| 1839 | assert(() { |
| 1840 | enabled = !debugDisableClipLayers; |
| 1841 | return true; |
| 1842 | }()); |
| 1843 | if (enabled) { |
| 1844 | engineLayer = builder.pushClipRSuperellipse( |
| 1845 | clipRSuperellipse!, |
| 1846 | clipBehavior: clipBehavior, |
| 1847 | oldLayer: _engineLayer as ui.ClipRSuperellipseEngineLayer?, |
| 1848 | ); |
| 1849 | } else { |
| 1850 | engineLayer = null; |
| 1851 | } |
| 1852 | addChildrenToScene(builder); |
| 1853 | if (enabled) { |
| 1854 | builder.pop(); |
| 1855 | } |
| 1856 | } |
| 1857 | |
| 1858 | @override |
| 1859 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1860 | super.debugFillProperties(properties); |
| 1861 | properties.add(DiagnosticsProperty<RSuperellipse>('clipRSuperellipse', clipRSuperellipse)); |
| 1862 | properties.add(DiagnosticsProperty<Clip>('clipBehavior', clipBehavior)); |
| 1863 | } |
| 1864 | } |
| 1865 | |
| 1866 | /// A composite layer that clips its children using a path. |
| 1867 | /// |
| 1868 | /// When debugging, setting [debugDisableClipLayers] to true will cause this |
| 1869 | /// layer to be skipped (directly replaced by its children). This can be helpful |
| 1870 | /// to track down the cause of performance problems. |
| 1871 | class ClipPathLayer extends ContainerLayer { |
| 1872 | /// Creates a layer with a path-based clip. |
| 1873 | /// |
| 1874 | /// The [clipPath] and [clipBehavior] properties must be non-null before the |
| 1875 | /// compositing phase of the pipeline. |
| 1876 | ClipPathLayer({Path? clipPath, Clip clipBehavior = Clip.antiAlias}) |
| 1877 | : _clipPath = clipPath, |
| 1878 | _clipBehavior = clipBehavior, |
| 1879 | assert(clipBehavior != Clip.none); |
| 1880 | |
| 1881 | /// The path to clip in the parent's coordinate system. |
| 1882 | /// |
| 1883 | /// The scene must be explicitly recomposited after this property is changed |
| 1884 | /// (as described at [Layer]). |
| 1885 | Path? get clipPath => _clipPath; |
| 1886 | Path? _clipPath; |
| 1887 | set clipPath(Path? value) { |
| 1888 | if (value != _clipPath) { |
| 1889 | _clipPath = value; |
| 1890 | markNeedsAddToScene(); |
| 1891 | } |
| 1892 | } |
| 1893 | |
| 1894 | @override |
| 1895 | Rect? describeClipBounds() => clipPath?.getBounds(); |
| 1896 | |
| 1897 | /// {@macro flutter.rendering.ClipRectLayer.clipBehavior} |
| 1898 | /// |
| 1899 | /// Defaults to [Clip.antiAlias]. |
| 1900 | Clip get clipBehavior => _clipBehavior; |
| 1901 | Clip _clipBehavior; |
| 1902 | set clipBehavior(Clip value) { |
| 1903 | assert(value != Clip.none); |
| 1904 | if (value != _clipBehavior) { |
| 1905 | _clipBehavior = value; |
| 1906 | markNeedsAddToScene(); |
| 1907 | } |
| 1908 | } |
| 1909 | |
| 1910 | @override |
| 1911 | bool findAnnotations<S extends Object>( |
| 1912 | AnnotationResult<S> result, |
| 1913 | Offset localPosition, { |
| 1914 | required bool onlyFirst, |
| 1915 | }) { |
| 1916 | if (!clipPath!.contains(localPosition)) { |
| 1917 | return false; |
| 1918 | } |
| 1919 | return super.findAnnotations<S>(result, localPosition, onlyFirst: onlyFirst); |
| 1920 | } |
| 1921 | |
| 1922 | @override |
| 1923 | void addToScene(ui.SceneBuilder builder) { |
| 1924 | assert(clipPath != null); |
| 1925 | bool enabled = true; |
| 1926 | assert(() { |
| 1927 | enabled = !debugDisableClipLayers; |
| 1928 | return true; |
| 1929 | }()); |
| 1930 | if (enabled) { |
| 1931 | engineLayer = builder.pushClipPath( |
| 1932 | clipPath!, |
| 1933 | clipBehavior: clipBehavior, |
| 1934 | oldLayer: _engineLayer as ui.ClipPathEngineLayer?, |
| 1935 | ); |
| 1936 | } else { |
| 1937 | engineLayer = null; |
| 1938 | } |
| 1939 | addChildrenToScene(builder); |
| 1940 | if (enabled) { |
| 1941 | builder.pop(); |
| 1942 | } |
| 1943 | } |
| 1944 | |
| 1945 | @override |
| 1946 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1947 | super.debugFillProperties(properties); |
| 1948 | properties.add(DiagnosticsProperty<Clip>('clipBehavior', clipBehavior)); |
| 1949 | } |
| 1950 | } |
| 1951 | |
| 1952 | /// A composite layer that applies a [ColorFilter] to its children. |
| 1953 | class ColorFilterLayer extends ContainerLayer { |
| 1954 | /// Creates a layer that applies a [ColorFilter] to its children. |
| 1955 | /// |
| 1956 | /// The [colorFilter] property must be non-null before the compositing phase |
| 1957 | /// of the pipeline. |
| 1958 | ColorFilterLayer({ColorFilter? colorFilter}) : _colorFilter = colorFilter; |
| 1959 | |
| 1960 | /// The color filter to apply to children. |
| 1961 | /// |
| 1962 | /// The scene must be explicitly recomposited after this property is changed |
| 1963 | /// (as described at [Layer]). |
| 1964 | ColorFilter? get colorFilter => _colorFilter; |
| 1965 | ColorFilter? _colorFilter; |
| 1966 | set colorFilter(ColorFilter? value) { |
| 1967 | assert(value != null); |
| 1968 | if (value != _colorFilter) { |
| 1969 | _colorFilter = value; |
| 1970 | markNeedsAddToScene(); |
| 1971 | } |
| 1972 | } |
| 1973 | |
| 1974 | @override |
| 1975 | void addToScene(ui.SceneBuilder builder) { |
| 1976 | assert(colorFilter != null); |
| 1977 | engineLayer = builder.pushColorFilter( |
| 1978 | colorFilter!, |
| 1979 | oldLayer: _engineLayer as ui.ColorFilterEngineLayer?, |
| 1980 | ); |
| 1981 | addChildrenToScene(builder); |
| 1982 | builder.pop(); |
| 1983 | } |
| 1984 | |
| 1985 | @override |
| 1986 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 1987 | super.debugFillProperties(properties); |
| 1988 | properties.add(DiagnosticsProperty<ColorFilter>('colorFilter', colorFilter)); |
| 1989 | } |
| 1990 | } |
| 1991 | |
| 1992 | /// A composite layer that applies an [ui.ImageFilter] to its children. |
| 1993 | class ImageFilterLayer extends OffsetLayer { |
| 1994 | /// Creates a layer that applies an [ui.ImageFilter] to its children. |
| 1995 | /// |
| 1996 | /// The [imageFilter] property must be non-null before the compositing phase |
| 1997 | /// of the pipeline. |
| 1998 | ImageFilterLayer({ui.ImageFilter? imageFilter, super.offset}) : _imageFilter = imageFilter; |
| 1999 | |
| 2000 | /// The image filter to apply to children. |
| 2001 | /// |
| 2002 | /// The scene must be explicitly recomposited after this property is changed |
| 2003 | /// (as described at [Layer]). |
| 2004 | ui.ImageFilter? get imageFilter => _imageFilter; |
| 2005 | ui.ImageFilter? _imageFilter; |
| 2006 | set imageFilter(ui.ImageFilter? value) { |
| 2007 | assert(value != null); |
| 2008 | if (value != _imageFilter) { |
| 2009 | _imageFilter = value; |
| 2010 | markNeedsAddToScene(); |
| 2011 | } |
| 2012 | } |
| 2013 | |
| 2014 | @override |
| 2015 | void addToScene(ui.SceneBuilder builder) { |
| 2016 | assert(imageFilter != null); |
| 2017 | engineLayer = builder.pushImageFilter( |
| 2018 | imageFilter!, |
| 2019 | offset: offset, |
| 2020 | oldLayer: _engineLayer as ui.ImageFilterEngineLayer?, |
| 2021 | ); |
| 2022 | addChildrenToScene(builder); |
| 2023 | builder.pop(); |
| 2024 | } |
| 2025 | |
| 2026 | @override |
| 2027 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2028 | super.debugFillProperties(properties); |
| 2029 | properties.add(DiagnosticsProperty<ui.ImageFilter>('imageFilter', imageFilter)); |
| 2030 | } |
| 2031 | } |
| 2032 | |
| 2033 | /// A composited layer that applies a given transformation matrix to its |
| 2034 | /// children. |
| 2035 | /// |
| 2036 | /// This class inherits from [OffsetLayer] to make it one of the layers that |
| 2037 | /// can be used at the root of a [RenderObject] hierarchy. |
| 2038 | class TransformLayer extends OffsetLayer { |
| 2039 | /// Creates a transform layer. |
| 2040 | /// |
| 2041 | /// The [transform] and [offset] properties must be non-null before the |
| 2042 | /// compositing phase of the pipeline. |
| 2043 | TransformLayer({Matrix4? transform, super.offset}) : _transform = transform; |
| 2044 | |
| 2045 | /// The matrix to apply. |
| 2046 | /// |
| 2047 | /// The scene must be explicitly recomposited after this property is changed |
| 2048 | /// (as described at [Layer]). |
| 2049 | /// |
| 2050 | /// This transform is applied before [offset], if both are set. |
| 2051 | /// |
| 2052 | /// The [transform] property must be non-null before the compositing phase of |
| 2053 | /// the pipeline. |
| 2054 | Matrix4? get transform => _transform; |
| 2055 | Matrix4? _transform; |
| 2056 | set transform(Matrix4? value) { |
| 2057 | assert(value != null); |
| 2058 | assert(value!.storage.every((double component) => component.isFinite)); |
| 2059 | if (value == _transform) { |
| 2060 | return; |
| 2061 | } |
| 2062 | _transform = value; |
| 2063 | _inverseDirty = true; |
| 2064 | markNeedsAddToScene(); |
| 2065 | } |
| 2066 | |
| 2067 | Matrix4? _lastEffectiveTransform; |
| 2068 | Matrix4? _invertedTransform; |
| 2069 | bool _inverseDirty = true; |
| 2070 | |
| 2071 | @override |
| 2072 | void addToScene(ui.SceneBuilder builder) { |
| 2073 | assert(transform != null); |
| 2074 | _lastEffectiveTransform = transform; |
| 2075 | if (offset != Offset.zero) { |
| 2076 | _lastEffectiveTransform = Matrix4.translationValues(offset.dx, offset.dy, 0.0) |
| 2077 | ..multiply(_lastEffectiveTransform!); |
| 2078 | } |
| 2079 | engineLayer = builder.pushTransform( |
| 2080 | _lastEffectiveTransform!.storage, |
| 2081 | oldLayer: _engineLayer as ui.TransformEngineLayer?, |
| 2082 | ); |
| 2083 | addChildrenToScene(builder); |
| 2084 | builder.pop(); |
| 2085 | } |
| 2086 | |
| 2087 | Offset? _transformOffset(Offset localPosition) { |
| 2088 | if (_inverseDirty) { |
| 2089 | _invertedTransform = Matrix4.tryInvert(PointerEvent.removePerspectiveTransform(transform!)); |
| 2090 | _inverseDirty = false; |
| 2091 | } |
| 2092 | if (_invertedTransform == null) { |
| 2093 | return null; |
| 2094 | } |
| 2095 | |
| 2096 | return MatrixUtils.transformPoint(_invertedTransform!, localPosition); |
| 2097 | } |
| 2098 | |
| 2099 | @override |
| 2100 | bool findAnnotations<S extends Object>( |
| 2101 | AnnotationResult<S> result, |
| 2102 | Offset localPosition, { |
| 2103 | required bool onlyFirst, |
| 2104 | }) { |
| 2105 | final Offset? transformedOffset = _transformOffset(localPosition); |
| 2106 | if (transformedOffset == null) { |
| 2107 | return false; |
| 2108 | } |
| 2109 | return super.findAnnotations<S>(result, transformedOffset, onlyFirst: onlyFirst); |
| 2110 | } |
| 2111 | |
| 2112 | @override |
| 2113 | void applyTransform(Layer? child, Matrix4 transform) { |
| 2114 | assert(child != null); |
| 2115 | assert(_lastEffectiveTransform != null || this.transform != null); |
| 2116 | if (_lastEffectiveTransform == null) { |
| 2117 | transform.multiply(this.transform!); |
| 2118 | } else { |
| 2119 | transform.multiply(_lastEffectiveTransform!); |
| 2120 | } |
| 2121 | } |
| 2122 | |
| 2123 | @override |
| 2124 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2125 | super.debugFillProperties(properties); |
| 2126 | properties.add(TransformProperty('transform', transform)); |
| 2127 | } |
| 2128 | } |
| 2129 | |
| 2130 | /// A composited layer that makes its children partially transparent. |
| 2131 | /// |
| 2132 | /// When debugging, setting [debugDisableOpacityLayers] to true will cause this |
| 2133 | /// layer to be skipped (directly replaced by its children). This can be helpful |
| 2134 | /// to track down the cause of performance problems. |
| 2135 | /// |
| 2136 | /// Try to avoid an [OpacityLayer] with no children. Remove that layer if |
| 2137 | /// possible to save some tree walks. |
| 2138 | class OpacityLayer extends OffsetLayer { |
| 2139 | /// Creates an opacity layer. |
| 2140 | /// |
| 2141 | /// The [alpha] property must be non-null before the compositing phase of |
| 2142 | /// the pipeline. |
| 2143 | OpacityLayer({int? alpha, super.offset}) : _alpha = alpha; |
| 2144 | |
| 2145 | /// The amount to multiply into the alpha channel. |
| 2146 | /// |
| 2147 | /// The opacity is expressed as an integer from 0 to 255, where 0 is fully |
| 2148 | /// transparent and 255 is fully opaque. |
| 2149 | /// |
| 2150 | /// The scene must be explicitly recomposited after this property is changed |
| 2151 | /// (as described at [Layer]). |
| 2152 | int? get alpha => _alpha; |
| 2153 | int? _alpha; |
| 2154 | set alpha(int? value) { |
| 2155 | assert(value != null); |
| 2156 | if (value != _alpha) { |
| 2157 | if (value == 255 || _alpha == 255) { |
| 2158 | engineLayer = null; |
| 2159 | } |
| 2160 | _alpha = value; |
| 2161 | markNeedsAddToScene(); |
| 2162 | } |
| 2163 | } |
| 2164 | |
| 2165 | @override |
| 2166 | void addToScene(ui.SceneBuilder builder) { |
| 2167 | assert(alpha != null); |
| 2168 | |
| 2169 | // Don't add this layer if there's no child. |
| 2170 | bool enabled = firstChild != null; |
| 2171 | if (!enabled) { |
| 2172 | // Ensure the engineLayer is disposed. |
| 2173 | engineLayer = null; |
| 2174 | // TODO(dnfield): Remove this if/when we can fix https://github.com/flutter/flutter/issues/90004 |
| 2175 | return; |
| 2176 | } |
| 2177 | |
| 2178 | assert(() { |
| 2179 | enabled = enabled && !debugDisableOpacityLayers; |
| 2180 | return true; |
| 2181 | }()); |
| 2182 | |
| 2183 | final int realizedAlpha = alpha!; |
| 2184 | // The type assertions work because the [alpha] setter nulls out the |
| 2185 | // engineLayer if it would have changed type (i.e. changed to or from 255). |
| 2186 | if (enabled && realizedAlpha < 255) { |
| 2187 | assert(_engineLayer is ui.OpacityEngineLayer?); |
| 2188 | engineLayer = builder.pushOpacity( |
| 2189 | realizedAlpha, |
| 2190 | offset: offset, |
| 2191 | oldLayer: _engineLayer as ui.OpacityEngineLayer?, |
| 2192 | ); |
| 2193 | } else { |
| 2194 | assert(_engineLayer is ui.OffsetEngineLayer?); |
| 2195 | engineLayer = builder.pushOffset( |
| 2196 | offset.dx, |
| 2197 | offset.dy, |
| 2198 | oldLayer: _engineLayer as ui.OffsetEngineLayer?, |
| 2199 | ); |
| 2200 | } |
| 2201 | addChildrenToScene(builder); |
| 2202 | builder.pop(); |
| 2203 | } |
| 2204 | |
| 2205 | @override |
| 2206 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2207 | super.debugFillProperties(properties); |
| 2208 | properties.add(IntProperty('alpha', alpha)); |
| 2209 | } |
| 2210 | } |
| 2211 | |
| 2212 | /// A composited layer that applies a shader to its children. |
| 2213 | /// |
| 2214 | /// The shader is only applied inside the given [maskRect]. The shader itself |
| 2215 | /// uses the top left of the [maskRect] as its origin. |
| 2216 | /// |
| 2217 | /// The [maskRect] does not affect the positions of any child layers. |
| 2218 | class ShaderMaskLayer extends ContainerLayer { |
| 2219 | /// Creates a shader mask layer. |
| 2220 | /// |
| 2221 | /// The [shader], [maskRect], and [blendMode] properties must be non-null |
| 2222 | /// before the compositing phase of the pipeline. |
| 2223 | ShaderMaskLayer({Shader? shader, Rect? maskRect, BlendMode? blendMode}) |
| 2224 | : _shader = shader, |
| 2225 | _maskRect = maskRect, |
| 2226 | _blendMode = blendMode; |
| 2227 | |
| 2228 | /// The shader to apply to the children. |
| 2229 | /// |
| 2230 | /// The origin of the shader (e.g. of the coordinate system used by the `from` |
| 2231 | /// and `to` arguments to [ui.Gradient.linear]) is at the top left of the |
| 2232 | /// [maskRect]. |
| 2233 | /// |
| 2234 | /// The scene must be explicitly recomposited after this property is changed |
| 2235 | /// (as described at [Layer]). |
| 2236 | /// |
| 2237 | /// See also: |
| 2238 | /// |
| 2239 | /// * [ui.Gradient] and [ui.ImageShader], two shader types that can be used. |
| 2240 | Shader? get shader => _shader; |
| 2241 | Shader? _shader; |
| 2242 | set shader(Shader? value) { |
| 2243 | if (value != _shader) { |
| 2244 | _shader = value; |
| 2245 | markNeedsAddToScene(); |
| 2246 | } |
| 2247 | } |
| 2248 | |
| 2249 | /// The position and size of the shader. |
| 2250 | /// |
| 2251 | /// The [shader] is only rendered inside this rectangle, using the top left of |
| 2252 | /// the rectangle as its origin. |
| 2253 | /// |
| 2254 | /// The scene must be explicitly recomposited after this property is changed |
| 2255 | /// (as described at [Layer]). |
| 2256 | Rect? get maskRect => _maskRect; |
| 2257 | Rect? _maskRect; |
| 2258 | set maskRect(Rect? value) { |
| 2259 | if (value != _maskRect) { |
| 2260 | _maskRect = value; |
| 2261 | markNeedsAddToScene(); |
| 2262 | } |
| 2263 | } |
| 2264 | |
| 2265 | /// The blend mode to apply when blending the shader with the children. |
| 2266 | /// |
| 2267 | /// The scene must be explicitly recomposited after this property is changed |
| 2268 | /// (as described at [Layer]). |
| 2269 | BlendMode? get blendMode => _blendMode; |
| 2270 | BlendMode? _blendMode; |
| 2271 | set blendMode(BlendMode? value) { |
| 2272 | if (value != _blendMode) { |
| 2273 | _blendMode = value; |
| 2274 | markNeedsAddToScene(); |
| 2275 | } |
| 2276 | } |
| 2277 | |
| 2278 | @override |
| 2279 | void addToScene(ui.SceneBuilder builder) { |
| 2280 | assert(shader != null); |
| 2281 | assert(maskRect != null); |
| 2282 | assert(blendMode != null); |
| 2283 | engineLayer = builder.pushShaderMask( |
| 2284 | shader!, |
| 2285 | maskRect!, |
| 2286 | blendMode!, |
| 2287 | oldLayer: _engineLayer as ui.ShaderMaskEngineLayer?, |
| 2288 | ); |
| 2289 | addChildrenToScene(builder); |
| 2290 | builder.pop(); |
| 2291 | } |
| 2292 | |
| 2293 | @override |
| 2294 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2295 | super.debugFillProperties(properties); |
| 2296 | properties.add(DiagnosticsProperty<Shader>('shader', shader)); |
| 2297 | properties.add(DiagnosticsProperty<Rect>('maskRect', maskRect)); |
| 2298 | properties.add(EnumProperty<BlendMode>('blendMode', blendMode)); |
| 2299 | } |
| 2300 | } |
| 2301 | |
| 2302 | /// A backdrop key uniquely identifies the backdrop that a [BackdropFilterLayer] |
| 2303 | /// samples from. |
| 2304 | /// |
| 2305 | /// When multiple backdrop filters share the same key, the Flutter engine can |
| 2306 | /// more efficiently perform the backdrop operations. |
| 2307 | /// |
| 2308 | /// Instead of using a backdrop key directly, consider using a [BackdropGroup] |
| 2309 | /// and the [BackdropFilter.grouped] constructor. The framework will |
| 2310 | /// automatically group child backdrop filters that use the `.grouped` |
| 2311 | /// constructor when they are placed as children of a [BackdropGroup]. |
| 2312 | /// |
| 2313 | /// For more information, see [BackdropFilter]. |
| 2314 | @immutable |
| 2315 | final class BackdropKey { |
| 2316 | /// Create a new [BackdropKey]. |
| 2317 | BackdropKey() : _key = _nextKey++; |
| 2318 | |
| 2319 | static int _nextKey = 0; |
| 2320 | |
| 2321 | final int _key; |
| 2322 | } |
| 2323 | |
| 2324 | /// A composited layer that applies a filter to the existing contents of the scene. |
| 2325 | class BackdropFilterLayer extends ContainerLayer { |
| 2326 | /// Creates a backdrop filter layer. |
| 2327 | /// |
| 2328 | /// The [filter] property must be non-null before the compositing phase of the |
| 2329 | /// pipeline. |
| 2330 | /// |
| 2331 | /// The [blendMode] property defaults to [BlendMode.srcOver]. |
| 2332 | BackdropFilterLayer({ui.ImageFilter? filter, BlendMode blendMode = BlendMode.srcOver}) |
| 2333 | : _filter = filter, |
| 2334 | _blendMode = blendMode; |
| 2335 | |
| 2336 | /// The filter to apply to the existing contents of the scene. |
| 2337 | /// |
| 2338 | /// The scene must be explicitly recomposited after this property is changed |
| 2339 | /// (as described at [Layer]). |
| 2340 | ui.ImageFilter? get filter => _filter; |
| 2341 | ui.ImageFilter? _filter; |
| 2342 | set filter(ui.ImageFilter? value) { |
| 2343 | if (value != _filter) { |
| 2344 | _filter = value; |
| 2345 | markNeedsAddToScene(); |
| 2346 | } |
| 2347 | } |
| 2348 | |
| 2349 | /// The blend mode to use to apply the filtered background content onto the background |
| 2350 | /// surface. |
| 2351 | /// |
| 2352 | /// The default value of this property is [BlendMode.srcOver]. |
| 2353 | /// {@macro flutter.widgets.BackdropFilter.blendMode} |
| 2354 | /// |
| 2355 | /// The scene must be explicitly recomposited after this property is changed |
| 2356 | /// (as described at [Layer]). |
| 2357 | BlendMode get blendMode => _blendMode; |
| 2358 | BlendMode _blendMode; |
| 2359 | set blendMode(BlendMode value) { |
| 2360 | if (value != _blendMode) { |
| 2361 | _blendMode = value; |
| 2362 | markNeedsAddToScene(); |
| 2363 | } |
| 2364 | } |
| 2365 | |
| 2366 | /// The backdrop key that identifies the [BackdropGroup] this filter will apply to. |
| 2367 | /// |
| 2368 | /// The default value for the backdrop key is `null`, meaning that it's not |
| 2369 | /// part of a [BackdropGroup]. |
| 2370 | /// |
| 2371 | /// The scene must be explicitly recomposited after this property is changed |
| 2372 | /// (as described at [Layer]). |
| 2373 | BackdropKey? get backdropKey => _backdropKey; |
| 2374 | BackdropKey? _backdropKey; |
| 2375 | set backdropKey(BackdropKey? value) { |
| 2376 | if (value != _backdropKey) { |
| 2377 | _backdropKey = value; |
| 2378 | markNeedsAddToScene(); |
| 2379 | } |
| 2380 | } |
| 2381 | |
| 2382 | @override |
| 2383 | void addToScene(ui.SceneBuilder builder) { |
| 2384 | assert(filter != null); |
| 2385 | engineLayer = builder.pushBackdropFilter( |
| 2386 | filter!, |
| 2387 | blendMode: blendMode, |
| 2388 | oldLayer: _engineLayer as ui.BackdropFilterEngineLayer?, |
| 2389 | backdropId: _backdropKey?._key, |
| 2390 | ); |
| 2391 | addChildrenToScene(builder); |
| 2392 | builder.pop(); |
| 2393 | } |
| 2394 | |
| 2395 | @override |
| 2396 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2397 | super.debugFillProperties(properties); |
| 2398 | properties.add(DiagnosticsProperty<ui.ImageFilter>('filter', filter)); |
| 2399 | properties.add(EnumProperty<BlendMode>('blendMode', blendMode)); |
| 2400 | properties.add(IntProperty('backdropKey', _backdropKey?._key)); |
| 2401 | } |
| 2402 | } |
| 2403 | |
| 2404 | /// An object that a [LeaderLayer] can register with. |
| 2405 | /// |
| 2406 | /// An instance of this class should be provided as the [LeaderLayer.link] and |
| 2407 | /// the [FollowerLayer.link] properties to cause the [FollowerLayer] to follow |
| 2408 | /// the [LeaderLayer]. |
| 2409 | /// |
| 2410 | /// See also: |
| 2411 | /// |
| 2412 | /// * [CompositedTransformTarget], the widget that creates a [LeaderLayer]. |
| 2413 | /// * [CompositedTransformFollower], the widget that creates a [FollowerLayer]. |
| 2414 | /// * [RenderLeaderLayer] and [RenderFollowerLayer], the corresponding |
| 2415 | /// render objects. |
| 2416 | class LayerLink { |
| 2417 | /// The [LeaderLayer] connected to this link. |
| 2418 | LeaderLayer? get leader => _leader; |
| 2419 | LeaderLayer? _leader; |
| 2420 | |
| 2421 | void _registerLeader(LeaderLayer leader) { |
| 2422 | assert(_leader != leader); |
| 2423 | assert(() { |
| 2424 | if (_leader != null) { |
| 2425 | _debugPreviousLeaders ??= <LeaderLayer>{}; |
| 2426 | _debugScheduleLeadersCleanUpCheck(); |
| 2427 | return _debugPreviousLeaders!.add(_leader!); |
| 2428 | } |
| 2429 | return true; |
| 2430 | }()); |
| 2431 | _leader = leader; |
| 2432 | } |
| 2433 | |
| 2434 | void _unregisterLeader(LeaderLayer leader) { |
| 2435 | if (_leader == leader) { |
| 2436 | _leader = null; |
| 2437 | } else { |
| 2438 | assert(_debugPreviousLeaders!.remove(leader)); |
| 2439 | } |
| 2440 | } |
| 2441 | |
| 2442 | /// Stores the previous leaders that were replaced by the current [_leader] |
| 2443 | /// in the current frame. |
| 2444 | /// |
| 2445 | /// These leaders need to give up their leaderships of this link by the end of |
| 2446 | /// the current frame. |
| 2447 | Set<LeaderLayer>? _debugPreviousLeaders; |
| 2448 | bool _debugLeaderCheckScheduled = false; |
| 2449 | |
| 2450 | /// Schedules the check as post frame callback to make sure the |
| 2451 | /// [_debugPreviousLeaders] is empty. |
| 2452 | void _debugScheduleLeadersCleanUpCheck() { |
| 2453 | assert(_debugPreviousLeaders != null); |
| 2454 | assert(() { |
| 2455 | if (_debugLeaderCheckScheduled) { |
| 2456 | return true; |
| 2457 | } |
| 2458 | _debugLeaderCheckScheduled = true; |
| 2459 | SchedulerBinding.instance.addPostFrameCallback((Duration timeStamp) { |
| 2460 | _debugLeaderCheckScheduled = false; |
| 2461 | assert(_debugPreviousLeaders!.isEmpty); |
| 2462 | }, debugLabel:'LayerLink.leadersCleanUpCheck'); |
| 2463 | return true; |
| 2464 | }()); |
| 2465 | } |
| 2466 | |
| 2467 | /// The total size of the content of the connected [LeaderLayer]. |
| 2468 | /// |
| 2469 | /// Generally this should be set by the [RenderObject] that paints on the |
| 2470 | /// registered [LeaderLayer] (for instance a [RenderLeaderLayer] that shares |
| 2471 | /// this link with its followers). This size may be outdated before and during |
| 2472 | /// layout. |
| 2473 | Size? leaderSize; |
| 2474 | |
| 2475 | @override |
| 2476 | String toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) { |
| 2477 | return'${describeIdentity(this)}(${_leader != null ?"<linked>":"<dangling>"})'; |
| 2478 | } |
| 2479 | } |
| 2480 | |
| 2481 | /// A composited layer that can be followed by a [FollowerLayer]. |
| 2482 | /// |
| 2483 | /// This layer collapses the accumulated offset into a transform and passes |
| 2484 | /// [Offset.zero] to its child layers in the [addToScene]/[addChildrenToScene] |
| 2485 | /// methods, so that [applyTransform] will work reliably. |
| 2486 | class LeaderLayer extends ContainerLayer { |
| 2487 | /// Creates a leader layer. |
| 2488 | /// |
| 2489 | /// The [link] property must not have been provided to any other [LeaderLayer] |
| 2490 | /// layers that are [attached] to the layer tree at the same time. |
| 2491 | /// |
| 2492 | /// The [offset] property must be non-null before the compositing phase of the |
| 2493 | /// pipeline. |
| 2494 | LeaderLayer({required LayerLink link, Offset offset = Offset.zero}) |
| 2495 | : _link = link, |
| 2496 | _offset = offset; |
| 2497 | |
| 2498 | /// The object with which this layer should register. |
| 2499 | /// |
| 2500 | /// The link will be established when this layer is [attach]ed, and will be |
| 2501 | /// cleared when this layer is [detach]ed. |
| 2502 | LayerLink get link => _link; |
| 2503 | LayerLink _link; |
| 2504 | set link(LayerLink value) { |
| 2505 | if (_link == value) { |
| 2506 | return; |
| 2507 | } |
| 2508 | if (attached) { |
| 2509 | _link._unregisterLeader(this); |
| 2510 | value._registerLeader(this); |
| 2511 | } |
| 2512 | _link = value; |
| 2513 | } |
| 2514 | |
| 2515 | /// Offset from parent in the parent's coordinate system. |
| 2516 | /// |
| 2517 | /// The scene must be explicitly recomposited after this property is changed |
| 2518 | /// (as described at [Layer]). |
| 2519 | /// |
| 2520 | /// The [offset] property must be non-null before the compositing phase of the |
| 2521 | /// pipeline. |
| 2522 | Offset get offset => _offset; |
| 2523 | Offset _offset; |
| 2524 | set offset(Offset value) { |
| 2525 | if (value == _offset) { |
| 2526 | return; |
| 2527 | } |
| 2528 | _offset = value; |
| 2529 | if (!alwaysNeedsAddToScene) { |
| 2530 | markNeedsAddToScene(); |
| 2531 | } |
| 2532 | } |
| 2533 | |
| 2534 | @override |
| 2535 | void attach(Object owner) { |
| 2536 | super.attach(owner); |
| 2537 | _link._registerLeader(this); |
| 2538 | } |
| 2539 | |
| 2540 | @override |
| 2541 | void detach() { |
| 2542 | _link._unregisterLeader(this); |
| 2543 | super.detach(); |
| 2544 | } |
| 2545 | |
| 2546 | @override |
| 2547 | bool findAnnotations<S extends Object>( |
| 2548 | AnnotationResult<S> result, |
| 2549 | Offset localPosition, { |
| 2550 | required bool onlyFirst, |
| 2551 | }) { |
| 2552 | return super.findAnnotations<S>(result, localPosition - offset, onlyFirst: onlyFirst); |
| 2553 | } |
| 2554 | |
| 2555 | @override |
| 2556 | void addToScene(ui.SceneBuilder builder) { |
| 2557 | if (offset != Offset.zero) { |
| 2558 | engineLayer = builder.pushTransform( |
| 2559 | Matrix4.translationValues(offset.dx, offset.dy, 0.0).storage, |
| 2560 | oldLayer: _engineLayer as ui.TransformEngineLayer?, |
| 2561 | ); |
| 2562 | } else { |
| 2563 | engineLayer = null; |
| 2564 | } |
| 2565 | addChildrenToScene(builder); |
| 2566 | if (offset != Offset.zero) { |
| 2567 | builder.pop(); |
| 2568 | } |
| 2569 | } |
| 2570 | |
| 2571 | /// Applies the transform that would be applied when compositing the given |
| 2572 | /// child to the given matrix. |
| 2573 | /// |
| 2574 | /// See [ContainerLayer.applyTransform] for details. |
| 2575 | /// |
| 2576 | /// The `child` argument may be null, as the same transform is applied to all |
| 2577 | /// children. |
| 2578 | @override |
| 2579 | void applyTransform(Layer? child, Matrix4 transform) { |
| 2580 | if (offset != Offset.zero) { |
| 2581 | transform.translate(offset.dx, offset.dy); |
| 2582 | } |
| 2583 | } |
| 2584 | |
| 2585 | @override |
| 2586 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2587 | super.debugFillProperties(properties); |
| 2588 | properties.add(DiagnosticsProperty<Offset>('offset', offset)); |
| 2589 | properties.add(DiagnosticsProperty<LayerLink>('link', link)); |
| 2590 | } |
| 2591 | } |
| 2592 | |
| 2593 | /// A composited layer that applies a transformation matrix to its children such |
| 2594 | /// that they are positioned to match a [LeaderLayer]. |
| 2595 | /// |
| 2596 | /// If any of the ancestors of this layer have a degenerate matrix (e.g. scaling |
| 2597 | /// by zero), then the [FollowerLayer] will not be able to transform its child |
| 2598 | /// to the coordinate space of the [LeaderLayer]. |
| 2599 | /// |
| 2600 | /// A [linkedOffset] property can be provided to further offset the child layer |
| 2601 | /// from the leader layer, for example if the child is to follow the linked |
| 2602 | /// layer at a distance rather than directly overlapping it. |
| 2603 | class FollowerLayer extends ContainerLayer { |
| 2604 | /// Creates a follower layer. |
| 2605 | /// |
| 2606 | /// The [unlinkedOffset], [linkedOffset], and [showWhenUnlinked] properties |
| 2607 | /// must be non-null before the compositing phase of the pipeline. |
| 2608 | FollowerLayer({ |
| 2609 | required this.link, |
| 2610 | this.showWhenUnlinked = true, |
| 2611 | this.unlinkedOffset = Offset.zero, |
| 2612 | this.linkedOffset = Offset.zero, |
| 2613 | }); |
| 2614 | |
| 2615 | /// The link to the [LeaderLayer]. |
| 2616 | /// |
| 2617 | /// The same object should be provided to a [LeaderLayer] that is earlier in |
| 2618 | /// the layer tree. When this layer is composited, it will apply a transform |
| 2619 | /// that moves its children to match the position of the [LeaderLayer]. |
| 2620 | LayerLink link; |
| 2621 | |
| 2622 | /// Whether to show the layer's contents when the [link] does not point to a |
| 2623 | /// [LeaderLayer]. |
| 2624 | /// |
| 2625 | /// When the layer is linked, children layers are positioned such that they |
| 2626 | /// have the same global position as the linked [LeaderLayer]. |
| 2627 | /// |
| 2628 | /// When the layer is not linked, then: if [showWhenUnlinked] is true, |
| 2629 | /// children are positioned as if the [FollowerLayer] was a [ContainerLayer]; |
| 2630 | /// if it is false, then children are hidden. |
| 2631 | /// |
| 2632 | /// The [showWhenUnlinked] property must be non-null before the compositing |
| 2633 | /// phase of the pipeline. |
| 2634 | bool? showWhenUnlinked; |
| 2635 | |
| 2636 | /// Offset from parent in the parent's coordinate system, used when the layer |
| 2637 | /// is not linked to a [LeaderLayer]. |
| 2638 | /// |
| 2639 | /// The scene must be explicitly recomposited after this property is changed |
| 2640 | /// (as described at [Layer]). |
| 2641 | /// |
| 2642 | /// The [unlinkedOffset] property must be non-null before the compositing |
| 2643 | /// phase of the pipeline. |
| 2644 | /// |
| 2645 | /// See also: |
| 2646 | /// |
| 2647 | /// * [linkedOffset], for when the layers are linked. |
| 2648 | Offset? unlinkedOffset; |
| 2649 | |
| 2650 | /// Offset from the origin of the leader layer to the origin of the child |
| 2651 | /// layers, used when the layer is linked to a [LeaderLayer]. |
| 2652 | /// |
| 2653 | /// The scene must be explicitly recomposited after this property is changed |
| 2654 | /// (as described at [Layer]). |
| 2655 | /// |
| 2656 | /// The [linkedOffset] property must be non-null before the compositing phase |
| 2657 | /// of the pipeline. |
| 2658 | /// |
| 2659 | /// See also: |
| 2660 | /// |
| 2661 | /// * [unlinkedOffset], for when the layer is not linked. |
| 2662 | Offset? linkedOffset; |
| 2663 | |
| 2664 | Offset? _lastOffset; |
| 2665 | Matrix4? _lastTransform; |
| 2666 | Matrix4? _invertedTransform; |
| 2667 | bool _inverseDirty = true; |
| 2668 | |
| 2669 | Offset? _transformOffset(Offset localPosition) { |
| 2670 | if (_inverseDirty) { |
| 2671 | _invertedTransform = Matrix4.tryInvert(getLastTransform()!); |
| 2672 | _inverseDirty = false; |
| 2673 | } |
| 2674 | if (_invertedTransform == null) { |
| 2675 | return null; |
| 2676 | } |
| 2677 | final Vector4 vector = Vector4(localPosition.dx, localPosition.dy, 0.0, 1.0); |
| 2678 | final Vector4 result = _invertedTransform!.transform(vector); |
| 2679 | return Offset(result[0] - linkedOffset!.dx, result[1] - linkedOffset!.dy); |
| 2680 | } |
| 2681 | |
| 2682 | @override |
| 2683 | bool findAnnotations<S extends Object>( |
| 2684 | AnnotationResult<S> result, |
| 2685 | Offset localPosition, { |
| 2686 | required bool onlyFirst, |
| 2687 | }) { |
| 2688 | if (link.leader == null) { |
| 2689 | if (showWhenUnlinked!) { |
| 2690 | return super.findAnnotations(result, localPosition - unlinkedOffset!, onlyFirst: onlyFirst); |
| 2691 | } |
| 2692 | return false; |
| 2693 | } |
| 2694 | final Offset? transformedOffset = _transformOffset(localPosition); |
| 2695 | if (transformedOffset == null) { |
| 2696 | return false; |
| 2697 | } |
| 2698 | return super.findAnnotations<S>(result, transformedOffset, onlyFirst: onlyFirst); |
| 2699 | } |
| 2700 | |
| 2701 | /// The transform that was used during the last composition phase. |
| 2702 | /// |
| 2703 | /// If the [link] was not linked to a [LeaderLayer], or if this layer has |
| 2704 | /// a degenerate matrix applied, then this will be null. |
| 2705 | /// |
| 2706 | /// This method returns a new [Matrix4] instance each time it is invoked. |
| 2707 | Matrix4? getLastTransform() { |
| 2708 | if (_lastTransform == null) { |
| 2709 | return null; |
| 2710 | } |
| 2711 | final Matrix4 result = Matrix4.translationValues(-_lastOffset!.dx, -_lastOffset!.dy, 0.0); |
| 2712 | result.multiply(_lastTransform!); |
| 2713 | return result; |
| 2714 | } |
| 2715 | |
| 2716 | /// Call [applyTransform] for each layer in the provided list. |
| 2717 | /// |
| 2718 | /// The list is in reverse order (deepest first). The first layer will be |
| 2719 | /// treated as the child of the second, and so forth. The first layer in the |
| 2720 | /// list won't have [applyTransform] called on it. The first layer may be |
| 2721 | /// null. |
| 2722 | static Matrix4 _collectTransformForLayerChain(List<ContainerLayer?> layers) { |
| 2723 | // Initialize our result matrix. |
| 2724 | final Matrix4 result = Matrix4.identity(); |
| 2725 | // Apply each layer to the matrix in turn, starting from the last layer, |
| 2726 | // and providing the previous layer as the child. |
| 2727 | for (int index = layers.length - 1; index > 0; index -= 1) { |
| 2728 | layers[index]?.applyTransform(layers[index - 1], result); |
| 2729 | } |
| 2730 | return result; |
| 2731 | } |
| 2732 | |
| 2733 | /// Find the common ancestor of two layers [a] and [b] by searching towards |
| 2734 | /// the root of the tree, and append each ancestor of [a] or [b] visited along |
| 2735 | /// the path to [ancestorsA] and [ancestorsB] respectively. |
| 2736 | /// |
| 2737 | /// Returns null if [a] [b] do not share a common ancestor, in which case the |
| 2738 | /// results in [ancestorsA] and [ancestorsB] are undefined. |
| 2739 | static Layer? _pathsToCommonAncestor( |
| 2740 | Layer? a, |
| 2741 | Layer? b, |
| 2742 | List<ContainerLayer?> ancestorsA, |
| 2743 | List<ContainerLayer?> ancestorsB, |
| 2744 | ) { |
| 2745 | // No common ancestor found. |
| 2746 | if (a == null || b == null) { |
| 2747 | return null; |
| 2748 | } |
| 2749 | |
| 2750 | if (identical(a, b)) { |
| 2751 | return a; |
| 2752 | } |
| 2753 | |
| 2754 | if (a.depth < b.depth) { |
| 2755 | ancestorsB.add(b.parent); |
| 2756 | return _pathsToCommonAncestor(a, b.parent, ancestorsA, ancestorsB); |
| 2757 | } else if (a.depth > b.depth) { |
| 2758 | ancestorsA.add(a.parent); |
| 2759 | return _pathsToCommonAncestor(a.parent, b, ancestorsA, ancestorsB); |
| 2760 | } |
| 2761 | |
| 2762 | ancestorsA.add(a.parent); |
| 2763 | ancestorsB.add(b.parent); |
| 2764 | return _pathsToCommonAncestor(a.parent, b.parent, ancestorsA, ancestorsB); |
| 2765 | } |
| 2766 | |
| 2767 | bool _debugCheckLeaderBeforeFollower( |
| 2768 | List<ContainerLayer> leaderToCommonAncestor, |
| 2769 | List<ContainerLayer> followerToCommonAncestor, |
| 2770 | ) { |
| 2771 | if (followerToCommonAncestor.length <= 1) { |
| 2772 | // Follower is the common ancestor, ergo the leader must come AFTER the follower. |
| 2773 | return false; |
| 2774 | } |
| 2775 | if (leaderToCommonAncestor.length <= 1) { |
| 2776 | // Leader is the common ancestor, ergo the leader must come BEFORE the follower. |
| 2777 | return true; |
| 2778 | } |
| 2779 | |
| 2780 | // Common ancestor is neither the leader nor the follower. |
| 2781 | final ContainerLayer leaderSubtreeBelowAncestor = |
| 2782 | leaderToCommonAncestor[leaderToCommonAncestor.length - 2]; |
| 2783 | final ContainerLayer followerSubtreeBelowAncestor = |
| 2784 | followerToCommonAncestor[followerToCommonAncestor.length - 2]; |
| 2785 | |
| 2786 | Layer? sibling = leaderSubtreeBelowAncestor; |
| 2787 | while (sibling != null) { |
| 2788 | if (sibling == followerSubtreeBelowAncestor) { |
| 2789 | return true; |
| 2790 | } |
| 2791 | sibling = sibling.nextSibling; |
| 2792 | } |
| 2793 | // The follower subtree didn't come after the leader subtree. |
| 2794 | return false; |
| 2795 | } |
| 2796 | |
| 2797 | /// Populate [_lastTransform] given the current state of the tree. |
| 2798 | void _establishTransform() { |
| 2799 | _lastTransform = null; |
| 2800 | final LeaderLayer? leader = link.leader; |
| 2801 | // Check to see if we are linked. |
| 2802 | if (leader == null) { |
| 2803 | return; |
| 2804 | } |
| 2805 | // If we're linked, check the link is valid. |
| 2806 | assert( |
| 2807 | leader.owner == owner, |
| 2808 | 'Linked LeaderLayer anchor is not in the same layer tree as the FollowerLayer.', |
| 2809 | ); |
| 2810 | |
| 2811 | // Stores [leader, ..., commonAncestor] after calling _pathsToCommonAncestor. |
| 2812 | final List<ContainerLayer> forwardLayers = <ContainerLayer>[leader]; |
| 2813 | // Stores [this (follower), ..., commonAncestor] after calling |
| 2814 | // _pathsToCommonAncestor. |
| 2815 | final List<ContainerLayer> inverseLayers = <ContainerLayer>[this]; |
| 2816 | |
| 2817 | final Layer? ancestor = _pathsToCommonAncestor(leader, this, forwardLayers, inverseLayers); |
| 2818 | assert(ancestor != null,'LeaderLayer and FollowerLayer do not have a common ancestor.'); |
| 2819 | assert( |
| 2820 | _debugCheckLeaderBeforeFollower(forwardLayers, inverseLayers), |
| 2821 | 'LeaderLayer anchor must come before FollowerLayer in paint order, but the reverse was true.', |
| 2822 | ); |
| 2823 | |
| 2824 | final Matrix4 forwardTransform = _collectTransformForLayerChain(forwardLayers); |
| 2825 | // Further transforms the coordinate system to a hypothetical child (null) |
| 2826 | // of the leader layer, to account for the leader's additional paint offset |
| 2827 | // and layer offset (LeaderLayer.offset). |
| 2828 | leader.applyTransform(null, forwardTransform); |
| 2829 | forwardTransform.translate(linkedOffset!.dx, linkedOffset!.dy); |
| 2830 | |
| 2831 | final Matrix4 inverseTransform = _collectTransformForLayerChain(inverseLayers); |
| 2832 | |
| 2833 | if (inverseTransform.invert() == 0.0) { |
| 2834 | // We are in a degenerate transform, so there's not much we can do. |
| 2835 | return; |
| 2836 | } |
| 2837 | // Combine the matrices and store the result. |
| 2838 | inverseTransform.multiply(forwardTransform); |
| 2839 | _lastTransform = inverseTransform; |
| 2840 | _inverseDirty = true; |
| 2841 | } |
| 2842 | |
| 2843 | /// {@template flutter.rendering.FollowerLayer.alwaysNeedsAddToScene} |
| 2844 | /// This disables retained rendering. |
| 2845 | /// |
| 2846 | /// A [FollowerLayer] copies changes from a [LeaderLayer] that could be anywhere |
| 2847 | /// in the Layer tree, and that leader layer could change without notifying the |
| 2848 | /// follower layer. Therefore we have to always call a follower layer's |
| 2849 | /// [addToScene]. In order to call follower layer's [addToScene], leader layer's |
| 2850 | /// [addToScene] must be called first so leader layer must also be considered |
| 2851 | /// as [alwaysNeedsAddToScene]. |
| 2852 | /// {@endtemplate} |
| 2853 | @override |
| 2854 | bool get alwaysNeedsAddToScene => true; |
| 2855 | |
| 2856 | @override |
| 2857 | void addToScene(ui.SceneBuilder builder) { |
| 2858 | assert(showWhenUnlinked != null); |
| 2859 | if (link.leader == null && !showWhenUnlinked!) { |
| 2860 | _lastTransform = null; |
| 2861 | _lastOffset = null; |
| 2862 | _inverseDirty = true; |
| 2863 | engineLayer = null; |
| 2864 | return; |
| 2865 | } |
| 2866 | _establishTransform(); |
| 2867 | if (_lastTransform != null) { |
| 2868 | _lastOffset = unlinkedOffset; |
| 2869 | engineLayer = builder.pushTransform( |
| 2870 | _lastTransform!.storage, |
| 2871 | oldLayer: _engineLayer as ui.TransformEngineLayer?, |
| 2872 | ); |
| 2873 | addChildrenToScene(builder); |
| 2874 | builder.pop(); |
| 2875 | } else { |
| 2876 | _lastOffset = null; |
| 2877 | final Matrix4 matrix = Matrix4.translationValues(unlinkedOffset!.dx, unlinkedOffset!.dy, .0); |
| 2878 | engineLayer = builder.pushTransform( |
| 2879 | matrix.storage, |
| 2880 | oldLayer: _engineLayer as ui.TransformEngineLayer?, |
| 2881 | ); |
| 2882 | addChildrenToScene(builder); |
| 2883 | builder.pop(); |
| 2884 | } |
| 2885 | _inverseDirty = true; |
| 2886 | } |
| 2887 | |
| 2888 | @override |
| 2889 | void applyTransform(Layer? child, Matrix4 transform) { |
| 2890 | assert(child != null); |
| 2891 | if (_lastTransform != null) { |
| 2892 | transform.multiply(_lastTransform!); |
| 2893 | } else { |
| 2894 | transform.multiply(Matrix4.translationValues(unlinkedOffset!.dx, unlinkedOffset!.dy, 0)); |
| 2895 | } |
| 2896 | } |
| 2897 | |
| 2898 | @override |
| 2899 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 2900 | super.debugFillProperties(properties); |
| 2901 | properties.add(DiagnosticsProperty<LayerLink>('link', link)); |
| 2902 | properties.add(TransformProperty('transform', getLastTransform(), defaultValue: null)); |
| 2903 | } |
| 2904 | } |
| 2905 | |
| 2906 | /// A composited layer which annotates its children with a value. Pushing this |
| 2907 | /// layer to the tree is the common way of adding an annotation. |
| 2908 | /// |
| 2909 | /// An annotation is an optional object of any type that, when attached with a |
| 2910 | /// layer, can be retrieved using [Layer.find] or [Layer.findAllAnnotations] |
| 2911 | /// with a position. The search process is done recursively, controlled by a |
| 2912 | /// concept of being opaque to a type of annotation, explained in the document |
| 2913 | /// of [Layer.findAnnotations]. |
| 2914 | /// |
| 2915 | /// When an annotation search arrives, this layer defers the same search to each |
| 2916 | /// of this layer's children, respecting their opacity. Then it adds this |
| 2917 | /// layer's annotation if all of the following restrictions are met: |
| 2918 | /// |
| 2919 | /// {@template flutter.rendering.AnnotatedRegionLayer.restrictions} |
| 2920 | /// * The target type must be identical to the annotated type `T`. |
| 2921 | /// * If [size] is provided, the target position must be contained within the |
| 2922 | /// rectangle formed by [size] and [offset]. |
| 2923 | /// {@endtemplate} |
| 2924 | /// |
| 2925 | /// This layer is opaque to a type of annotation if any child is also opaque, or |
| 2926 | /// if [opaque] is true and the layer's annotation is added. |
| 2927 | class AnnotatedRegionLayer<T extends Object> extends ContainerLayer { |
| 2928 | /// Creates a new layer that annotates its children with [value]. |
| 2929 | AnnotatedRegionLayer(this.value, {this.size, Offset? offset, this.opaque = false}) |
| 2930 | : offset = offset ?? Offset.zero; |
| 2931 | |
| 2932 | /// The annotated object, which is added to the result if all restrictions are |
| 2933 | /// met. |
| 2934 | final T value; |
| 2935 | |
| 2936 | /// The size of the annotated object. |
| 2937 | /// |
| 2938 | /// If [size] is provided, then the annotation is found only if the target |
| 2939 | /// position is contained by the rectangle formed by [size] and [offset]. |
| 2940 | /// Otherwise no such restriction is applied, and clipping can only be done by |
| 2941 | /// the ancestor layers. |
| 2942 | final Size? size; |
| 2943 | |
| 2944 | /// The position of the annotated object. |
| 2945 | /// |
| 2946 | /// The [offset] defaults to [Offset.zero] if not provided, and is ignored if |
| 2947 | /// [size] is not set. |
| 2948 | /// |
| 2949 | /// The [offset] only offsets the clipping rectangle, and does not affect |
| 2950 | /// how the painting or annotation search is propagated to its children. |
| 2951 | final Offset offset; |
| 2952 | |
| 2953 | /// Whether the annotation of this layer should be opaque during an annotation |
| 2954 | /// search of type `T`, preventing siblings visually behind it from being |
| 2955 | /// searched. |
| 2956 | /// |
| 2957 | /// If [opaque] is true, and this layer does add its annotation [value], |
| 2958 | /// then the layer will always be opaque during the search. |
| 2959 | /// |
| 2960 | /// If [opaque] is false, or if this layer does not add its annotation, |
| 2961 | /// then the opacity of this layer will be the one returned by the children, |
| 2962 | /// meaning that it will be opaque if any child is opaque. |
| 2963 | /// |
| 2964 | /// The [opaque] defaults to false. |
| 2965 | /// |
| 2966 | /// The [opaque] is effectively useless during [Layer.find] (more |
| 2967 | /// specifically, [Layer.findAnnotations] with `onlyFirst: true`), since the |
| 2968 | /// search process then skips the remaining tree after finding the first |
| 2969 | /// annotation. |
| 2970 | /// |
| 2971 | /// See also: |
| 2972 | /// |
| 2973 | /// * [Layer.findAnnotations], which explains the concept of being opaque |
| 2974 | /// to a type of annotation as the return value. |
| 2975 | /// * [HitTestBehavior], which controls similar logic when hit-testing in the |
| 2976 | /// render tree. |
| 2977 | final bool opaque; |
| 2978 | |
| 2979 | /// Searches the subtree for annotations of type `S` at the location |
| 2980 | /// `localPosition`, then adds the annotation [value] if applicable. |
| 2981 | /// |
| 2982 | /// This method always searches its children, and if any child returns `true`, |
| 2983 | /// the remaining children are skipped. Regardless of what the children |
| 2984 | /// return, this method then adds this layer's annotation if all of the |
| 2985 | /// following restrictions are met: |
| 2986 | /// |
| 2987 | /// {@macro flutter.rendering.AnnotatedRegionLayer.restrictions} |
| 2988 | /// |
| 2989 | /// This search process respects `onlyFirst`, meaning that when `onlyFirst` is |
| 2990 | /// true, the search will stop when it finds the first annotation from the |
| 2991 | /// children, and the layer's own annotation is checked only when none is |
| 2992 | /// given by the children. |
| 2993 | /// |
| 2994 | /// The return value is true if any child returns `true`, or if [opaque] is |
| 2995 | /// true and the layer's annotation is added. |
| 2996 | /// |
| 2997 | /// For explanation of layer annotations, parameters and return value, refer |
| 2998 | /// to [Layer.findAnnotations]. |
| 2999 | @override |
| 3000 | bool findAnnotations<S extends Object>( |
| 3001 | AnnotationResult<S> result, |
| 3002 | Offset localPosition, { |
| 3003 | required bool onlyFirst, |
| 3004 | }) { |
| 3005 | bool isAbsorbed = super.findAnnotations(result, localPosition, onlyFirst: onlyFirst); |
| 3006 | if (result.entries.isNotEmpty && onlyFirst) { |
| 3007 | return isAbsorbed; |
| 3008 | } |
| 3009 | if (size != null && !(offset & size!).contains(localPosition)) { |
| 3010 | return isAbsorbed; |
| 3011 | } |
| 3012 | if (T == S) { |
| 3013 | isAbsorbed = isAbsorbed || opaque; |
| 3014 | final Object untypedValue = value; |
| 3015 | final S typedValue = untypedValue as S; |
| 3016 | result.add(AnnotationEntry<S>(annotation: typedValue, localPosition: localPosition - offset)); |
| 3017 | } |
| 3018 | return isAbsorbed; |
| 3019 | } |
| 3020 | |
| 3021 | @override |
| 3022 | void debugFillProperties(DiagnosticPropertiesBuilder properties) { |
| 3023 | super.debugFillProperties(properties); |
| 3024 | properties.add(DiagnosticsProperty<T>('value', value)); |
| 3025 | properties.add(DiagnosticsProperty<Size>('size', size, defaultValue: null)); |
| 3026 | properties.add(DiagnosticsProperty<Offset>('offset', offset, defaultValue: null)); |
| 3027 | properties.add(DiagnosticsProperty<bool>('opaque', opaque, defaultValue: false)); |
| 3028 | } |
| 3029 | } |
| 3030 |
Definitions
- AnnotationEntry
- AnnotationEntry
- toString
- AnnotationResult
- add
- entries
- annotations
- Layer
- Layer
- subtreeHasCompositionCallbacks
- _updateSubtreeCompositionObserverCount
- _fireCompositionCallbacks
- supportsRasterization
- describeClipBounds
- addCompositionCallback
- debugDisposed
- _unref
- debugHandleCount
- dispose
- parent
- markNeedsAddToScene
- debugMarkClean
- alwaysNeedsAddToScene
- debugSubtreeNeedsAddToScene
- engineLayer
- engineLayer
- updateSubtreeNeedsAddToScene
- owner
- attached
- attach
- detach
- depth
- redepthChildren
- nextSibling
- previousSibling
- remove
- findAnnotations
- find
- findAllAnnotations
- addToScene
- _addToSceneWithRetainedRendering
- toStringShort
- debugFillProperties
- LayerHandle
- LayerHandle
- layer
- layer
- toString
- PictureLayer
- PictureLayer
- picture
- picture
- isComplexHint
- isComplexHint
- willChangeHint
- willChangeHint
- dispose
- addToScene
- debugFillProperties
- findAnnotations
- TextureLayer
- TextureLayer
- addToScene
- findAnnotations
- PlatformViewLayer
- PlatformViewLayer
- supportsRasterization
- addToScene
- PerformanceOverlayLayer
- PerformanceOverlayLayer
- overlayRect
- overlayRect
- addToScene
- findAnnotations
- ContainerLayer
- _fireCompositionCallbacks
- firstChild
- lastChild
- hasChildren
- supportsRasterization
- buildScene
- _debugUltimatePreviousSiblingOf
- _debugUltimateNextSiblingOf
- dispose
- updateSubtreeNeedsAddToScene
- findAnnotations
- attach
- detach
- append
- _adoptChild
- redepthChildren
- redepthChild
- _removeChild
- _dropChild
- removeAllChildren
- addToScene
- addChildrenToScene
- applyTransform
- depthFirstIterateChildren
- debugDescribeChildren
- OffsetLayer
- OffsetLayer
- offset
- offset
- findAnnotations
- applyTransform
- addToScene
- debugFillProperties
- _createSceneForImage
- toImage
- toImageSync
- ClipRectLayer
- ClipRectLayer
- clipRect
- clipRect
- describeClipBounds
- clipBehavior
- clipBehavior
- findAnnotations
- addToScene
- debugFillProperties
- ClipRRectLayer
- ClipRRectLayer
- clipRRect
- clipRRect
- describeClipBounds
- clipBehavior
- clipBehavior
- findAnnotations
- addToScene
- debugFillProperties
- ClipRSuperellipseLayer
- ClipRSuperellipseLayer
- clipRSuperellipse
- clipRSuperellipse
- describeClipBounds
- clipBehavior
- clipBehavior
- findAnnotations
- addToScene
- debugFillProperties
- ClipPathLayer
- ClipPathLayer
- clipPath
- clipPath
- describeClipBounds
- clipBehavior
- clipBehavior
- findAnnotations
- addToScene
- debugFillProperties
- ColorFilterLayer
- ColorFilterLayer
- colorFilter
- colorFilter
- addToScene
- debugFillProperties
- ImageFilterLayer
- ImageFilterLayer
- imageFilter
- imageFilter
- addToScene
- debugFillProperties
- TransformLayer
- TransformLayer
- transform
- transform
- addToScene
- _transformOffset
- findAnnotations
- applyTransform
- debugFillProperties
- OpacityLayer
- OpacityLayer
- alpha
- alpha
- addToScene
- debugFillProperties
- ShaderMaskLayer
- ShaderMaskLayer
- shader
- shader
- maskRect
- maskRect
- blendMode
- blendMode
- addToScene
- debugFillProperties
- BackdropKey
- BackdropKey
- BackdropFilterLayer
- BackdropFilterLayer
- filter
- filter
- blendMode
- blendMode
- backdropKey
- backdropKey
- addToScene
- debugFillProperties
- LayerLink
- leader
- _registerLeader
- _unregisterLeader
- _debugScheduleLeadersCleanUpCheck
- toString
- LeaderLayer
- LeaderLayer
- link
- link
- offset
- offset
- attach
- detach
- findAnnotations
- addToScene
- applyTransform
- debugFillProperties
- FollowerLayer
- FollowerLayer
- _transformOffset
- findAnnotations
- getLastTransform
- _collectTransformForLayerChain
- _pathsToCommonAncestor
- _debugCheckLeaderBeforeFollower
- _establishTransform
- alwaysNeedsAddToScene
- addToScene
- applyTransform
- debugFillProperties
- AnnotatedRegionLayer
- AnnotatedRegionLayer
- findAnnotations
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