[web:canvaskit] switch to temporary SkPaint objects

Author: yjbanov

lib/web_ui/lib/painting.dart

@@ -325,14 +325,6 @@ abstract class Paint {
   factory Paint() => engine.renderer.createPaint();
 
   factory Paint.from(Paint other) {
-    // This is less efficient than copying the underlying buffer or object but
-    // it's a reasonable default, as if a user wanted to implement a copy of a
-    // paint object themselves they are unable to do much better than this.
-    //
-    // TODO(matanlurey): Web team, if important to optimize, could:
-    // 1. Add a `engine.renderer.copyPaint` method.
-    // 2. Use the below code as the default implementation.
-    // 3. Have renderer-specific implementations override with optimized code.
     final Paint paint = Paint();
     paint
       ..blendMode = other.blendMode

lib/web_ui/lib/src/engine/canvaskit/canvas.dart

@@ -80,13 +80,16 @@ class CkCanvas {
     CkPaint paint,
   ) {
     const double toDegrees = 180 / math.pi;
+
+    final skPaint = paint.toSkPaint();
     skCanvas.drawArc(
       toSkRect(oval),
       startAngle * toDegrees,
       sweepAngle * toDegrees,
       useCenter,
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   // TODO(flar): CanvasKit does not expose sampling options available on SkCanvas.drawAtlas
@@ -98,23 +101,27 @@ class CkCanvas {
     Uint32List? colors,
     ui.BlendMode blendMode,
   ) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawAtlas(
       atlas.skImage,
       rects,
       rstTransforms,
-      paint.skiaObject,
+      skPaint,
       toSkBlendMode(blendMode),
       colors,
     );
+    skPaint.delete();
   }
 
   void drawCircle(ui.Offset c, double radius, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawCircle(
       c.dx,
       c.dy,
       radius,
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawColor(ui.Color color, ui.BlendMode blendMode) {
@@ -125,23 +132,26 @@ class CkCanvas {
   }
 
   void drawDRRect(ui.RRect outer, ui.RRect inner, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawDRRect(
       toSkRRect(outer),
       toSkRRect(inner),
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawImage(CkImage image, ui.Offset offset, CkPaint paint) {
     final ui.FilterQuality filterQuality = paint.filterQuality;
+    final skPaint = paint.toSkPaint();
     if (filterQuality == ui.FilterQuality.high) {
       skCanvas.drawImageCubic(
         image.skImage,
         offset.dx,
         offset.dy,
         _kMitchellNetravali_B,
         _kMitchellNetravali_C,
-        paint.skiaObject,
+        skPaint,
       );
     } else {
       skCanvas.drawImageOptions(
@@ -150,21 +160,23 @@ class CkCanvas {
         offset.dy,
         toSkFilterMode(filterQuality),
         toSkMipmapMode(filterQuality),
-        paint.skiaObject,
+        skPaint,
       );
     }
+    skPaint.delete();
   }
 
   void drawImageRect(CkImage image, ui.Rect src, ui.Rect dst, CkPaint paint) {
     final ui.FilterQuality filterQuality = paint.filterQuality;
+    final skPaint = paint.toSkPaint();
     if (filterQuality == ui.FilterQuality.high) {
       skCanvas.drawImageRectCubic(
         image.skImage,
         toSkRect(src),
         toSkRect(dst),
         _kMitchellNetravali_B,
         _kMitchellNetravali_C,
-        paint.skiaObject,
+        skPaint,
       );
     } else {
       skCanvas.drawImageRectOptions(
@@ -173,41 +185,50 @@ class CkCanvas {
         toSkRect(dst),
         toSkFilterMode(filterQuality),
         toSkMipmapMode(filterQuality),
-        paint.skiaObject,
+        skPaint,
       );
     }
+    skPaint.delete();
   }
 
   void drawImageNine(
       CkImage image, ui.Rect center, ui.Rect dst, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawImageNine(
       image.skImage,
       toSkRect(center),
       toSkRect(dst),
       toSkFilterMode(paint.filterQuality),
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawLine(ui.Offset p1, ui.Offset p2, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawLine(
       p1.dx,
       p1.dy,
       p2.dx,
       p2.dy,
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawOval(ui.Rect rect, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawOval(
       toSkRect(rect),
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawPaint(CkPaint paint) {
-    skCanvas.drawPaint(paint.skiaObject);
+    final skPaint = paint.toSkPaint();
+    skCanvas.drawPaint(skPaint);
+    skPaint.delete();
   }
 
   void drawParagraph(CkParagraph paragraph, ui.Offset offset) {
@@ -219,7 +240,9 @@ class CkCanvas {
   }
 
   void drawPath(CkPath path, CkPaint paint) {
-    skCanvas.drawPath(path.skiaObject, paint.skiaObject);
+    final skPaint = paint.toSkPaint();
+    skCanvas.drawPath(path.skiaObject, skPaint);
+    skPaint.delete();
   }
 
   void drawPicture(CkPicture picture) {
@@ -228,22 +251,28 @@ class CkCanvas {
   }
 
   void drawPoints(CkPaint paint, ui.PointMode pointMode, Float32List points) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawPoints(
       toSkPointMode(pointMode),
       points,
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawRRect(ui.RRect rrect, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawRRect(
       toSkRRect(rrect),
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void drawRect(ui.Rect rect, CkPaint paint) {
-    skCanvas.drawRect(toSkRect(rect), paint.skiaObject);
+    final skPaint = paint.toSkPaint();
+    skCanvas.drawRect(toSkRect(rect), skPaint);
+    skPaint.delete();
   }
 
   void drawShadow(
@@ -254,11 +283,13 @@ class CkCanvas {
 
   void drawVertices(
       CkVertices vertices, ui.BlendMode blendMode, CkPaint paint) {
+    final skPaint = paint.toSkPaint();
     skCanvas.drawVertices(
       vertices.skiaObject,
       toSkBlendMode(blendMode),
-      paint.skiaObject,
+      skPaint,
     );
+    skPaint.delete();
   }
 
   void restore() {
@@ -278,16 +309,20 @@ class CkCanvas {
   }
 
   void saveLayer(ui.Rect bounds, CkPaint? paint) {
+    final skPaint = paint?.toSkPaint();
     skCanvas.saveLayer(
-      paint?.skiaObject,
+      skPaint,
       toSkRect(bounds),
       null,
       null,
     );
+    skPaint?.delete();
   }
 
   void saveLayerWithoutBounds(CkPaint? paint) {
-    skCanvas.saveLayer(paint?.skiaObject, null, null, null);
+    final skPaint = paint?.toSkPaint();
+    skCanvas.saveLayer(skPaint, null, null, null);
+    skPaint?.delete();
   }
 
   void saveLayerWithFilter(ui.Rect bounds, ui.ImageFilter filter,
@@ -299,12 +334,14 @@ class CkCanvas {
       convertible = filter as CkManagedSkImageFilterConvertible;
     }
     convertible.imageFilter((SkImageFilter filter) {
+      final skPaint = paint?.toSkPaint();
       skCanvas.saveLayer(
-        paint?.skiaObject,
+        skPaint,
         toSkRect(bounds),
         filter,
         0,
       );
+      skPaint?.delete();
     });
   }
 

lib/web_ui/lib/src/engine/canvaskit/image.dart

@@ -300,7 +300,6 @@ CkImage scaleImage(SkImage image, int? targetWidth, int? targetHeight) {
     ui.Rect.fromLTWH(0, 0, targetWidth!.toDouble(), targetHeight!.toDouble()),
     paint,
   );
-  paint.dispose();
 
   final CkPicture picture = recorder.endRecording();
   final ui.Image finalImage = picture.toImageSync(targetWidth, targetHeight);

lib/web_ui/lib/src/engine/canvaskit/layer.dart

@@ -187,7 +187,6 @@ class BackdropFilterEngineLayer extends ContainerLayer
     // single canvas, the backdrop filter will be applied multiple times.
     final CkCanvas currentCanvas = paintContext.leafNodesCanvas!;
     currentCanvas.saveLayerWithFilter(paintBounds, _filter, paint);
-    paint.dispose();
     paintChildren(paintContext);
     currentCanvas.restore();
   }
@@ -349,7 +348,6 @@ class OpacityEngineLayer extends ContainerLayer
     final ui.Rect saveLayerBounds = paintBounds.shift(-_offset);
 
     paintContext.internalNodesCanvas.saveLayer(saveLayerBounds, paint);
-    paint.dispose();
     paintChildren(paintContext);
     // Restore twice: once for the translate and once for the saveLayer.
     paintContext.internalNodesCanvas.restore();
@@ -442,7 +440,6 @@ class ImageFilterEngineLayer extends ContainerLayer
     final CkPaint paint = CkPaint();
     paint.imageFilter = _filter;
     paintContext.internalNodesCanvas.saveLayer(paintBounds, paint);
-    paint.dispose();
     paintChildren(paintContext);
     paintContext.internalNodesCanvas.restore();
     paintContext.internalNodesCanvas.restore();
@@ -479,7 +476,6 @@ class ShaderMaskEngineLayer extends ContainerLayer
 
     paintContext.leafNodesCanvas!.drawRect(
         ui.Rect.fromLTWH(0, 0, maskRect.width, maskRect.height), paint);
-    paint.dispose();
     paintContext.leafNodesCanvas!.restore();
 
     paintContext.internalNodesCanvas.restore();
@@ -547,7 +543,6 @@ class ColorFilterEngineLayer extends ContainerLayer
     paintChildren(paintContext);
     paintContext.internalNodesCanvas.restore();
     paintContext.internalNodesCanvas.restore();
-    paint.dispose();
   }
 }
 

lib/web_ui/lib/src/engine/canvaskit/mask_filter.dart

@@ -5,25 +5,14 @@
 import 'package:ui/ui.dart' as ui;
 
 import 'canvaskit_api.dart';
-import 'native_memory.dart';
 
-/// The CanvasKit implementation of [ui.MaskFilter].
-class CkMaskFilter {
-  CkMaskFilter.blur(ui.BlurStyle blurStyle, double sigma)
-      : _blurStyle = blurStyle,
-        _sigma = sigma {
-    final SkMaskFilter skMaskFilter = canvasKit.MaskFilter.MakeBlur(
-      toSkBlurStyle(_blurStyle),
-      _sigma,
-      true,
-    )!;
-    _ref = UniqueRef<SkMaskFilter>(this, skMaskFilter, 'MaskFilter');
-  }
-
-  final ui.BlurStyle _blurStyle;
-  final double _sigma;
-
-  late final UniqueRef<SkMaskFilter> _ref;
-
-  SkMaskFilter get skiaObject => _ref.nativeObject;
+/// Creates and returns a [SkMaskFilter] that applies a blur effect.
+///
+/// It is the responsibility of the caller to delete the returned Skia object.
+SkMaskFilter createBlurSkMaskFilter(ui.BlurStyle blurStyle, double sigma) {
+  return canvasKit.MaskFilter.MakeBlur(
+    toSkBlurStyle(blurStyle),
+    sigma,
+    true,
+  )!;
 }