encode DPR for shadows into DisplayList (#27289)

flow/display_list.cc

@@ -796,24 +796,28 @@ struct DrawTextBlobOp final : DLOp {
 };
 
 // 4 byte header + 28 byte payload packs evenly into 32 bytes
-struct DrawShadowOp final : DLOp {
-  static const auto kType = DisplayListOpType::kDrawShadow;
-
-  DrawShadowOp(const SkPath& path,
-               SkColor color,
-               SkScalar elevation,
-               bool occludes)
-      : color(color), elevation(elevation), occludes(occludes), path(path) {}
-
-  const SkColor color;
-  const SkScalar elevation;
-  const bool occludes;
-  const SkPath path;
-
-  void dispatch(Dispatcher& dispatcher) const {
-    dispatcher.drawShadow(path, color, elevation, occludes);
-  }
-};
+#define DEFINE_DRAW_SHADOW_OP(name, occludes)                         \
+  struct Draw##name##Op final : DLOp {                                \
+    static const auto kType = DisplayListOpType::kDraw##name;         \
+                                                                      \
+    Draw##name##Op(const SkPath& path,                                \
+                   SkColor color,                                     \
+                   SkScalar elevation,                                \
+                   SkScalar dpr)                                      \
+        : color(color), elevation(elevation), dpr(dpr), path(path) {} \
+                                                                      \
+    const SkColor color;                                              \
+    const SkScalar elevation;                                         \
+    const SkScalar dpr;                                               \
+    const SkPath path;                                                \
+                                                                      \
+    void dispatch(Dispatcher& dispatcher) const {                     \
+      dispatcher.drawShadow(path, color, elevation, occludes, dpr);   \
+    }                                                                 \
+  };
+DEFINE_DRAW_SHADOW_OP(Shadow, false)
+DEFINE_DRAW_SHADOW_OP(ShadowOccludes, true)
+#undef DEFINE_DRAW_SHADOW_OP
 
 #pragma pack(pop, DLOp_Alignment)
 
@@ -1351,8 +1355,11 @@ void DisplayListBuilder::drawTextBlob(const sk_sp<SkTextBlob> blob,
 void DisplayListBuilder::drawShadow(const SkPath& path,
                                     const SkColor color,
                                     const SkScalar elevation,
-                                    bool occludes) {
-  Push<DrawShadowOp>(0, path, color, elevation, occludes);
+                                    bool occludes,
+                                    SkScalar dpr) {
+  occludes  //
+      ? Push<DrawShadowOccludesOp>(0, path, color, elevation, dpr)
+      : Push<DrawShadowOp>(0, path, color, elevation, dpr);
 }
 
 }  // namespace flutter

flow/display_list.h

@@ -144,7 +144,8 @@ namespace flutter {
   V(DrawDisplayList)                \
   V(DrawTextBlob)                   \
                                     \
-  V(DrawShadow)
+  V(DrawShadow)                     \
+  V(DrawShadowOccludes)
 
 #define DL_OP_TO_ENUM_VALUE(name) k##name,
 enum class DisplayListOpType { FOR_EACH_DISPLAY_LIST_OP(DL_OP_TO_ENUM_VALUE) };
@@ -318,7 +319,8 @@ class Dispatcher {
   virtual void drawShadow(const SkPath& path,
                           const SkColor color,
                           const SkScalar elevation,
-                          bool occludes) = 0;
+                          bool occludes,
+                          SkScalar dpr) = 0;
 };
 
 // The primary class used to build a display list. The list of methods
@@ -431,7 +433,8 @@ class DisplayListBuilder final : public virtual Dispatcher, public SkRefCnt {
   void drawShadow(const SkPath& path,
                   const SkColor color,
                   const SkScalar elevation,
-                  bool occludes) override;
+                  bool occludes,
+                  SkScalar dpr) override;
 
   sk_sp<DisplayList> Build();
 

flow/display_list_canvas.cc

@@ -176,9 +176,10 @@ void DisplayListCanvasDispatcher::drawTextBlob(const sk_sp<SkTextBlob> blob,
 void DisplayListCanvasDispatcher::drawShadow(const SkPath& path,
                                              const SkColor color,
                                              const SkScalar elevation,
-                                             bool occludes) {
+                                             bool occludes,
+                                             SkScalar dpr) {
   flutter::PhysicalShapeLayer::DrawShadow(canvas_, path, color, elevation,
-                                          occludes, 1.0);
+                                          occludes, dpr);
 }
 
 DisplayListCanvasRecorder::DisplayListCanvasRecorder(const SkRect& bounds)

flow/display_list_canvas.h

@@ -110,7 +110,8 @@ class DisplayListCanvasDispatcher : public virtual Dispatcher,
   void drawShadow(const SkPath& path,
                   const SkColor color,
                   const SkScalar elevation,
-                  bool occludes) override;
+                  bool occludes,
+                  SkScalar dpr) override;
 
  private:
   SkCanvas* canvas_;

flow/display_list_canvas_unittests.cc

@@ -1350,7 +1350,7 @@ TEST(DisplayListCanvas, DrawShadow) {
                                        1.0);
       },
       [=](DisplayListBuilder& builder) {  //
-        builder.drawShadow(path, color, elevation, false);
+        builder.drawShadow(path, color, elevation, false, 1.0);
       });
   CanvasCompareTester::UsingShadows = false;
 }
@@ -1373,7 +1373,30 @@ TEST(DisplayListCanvas, DrawOccludingShadow) {
                                        1.0);
       },
       [=](DisplayListBuilder& builder) {  //
-        builder.drawShadow(path, color, elevation, true);
+        builder.drawShadow(path, color, elevation, true, 1.0);
+      });
+  CanvasCompareTester::UsingShadows = false;
+}
+
+TEST(DisplayListCanvas, DrawShadowDpr) {
+  CanvasCompareTester::UsingShadows = true;
+  SkPath path;
+  path.moveTo(RenderCenterX, RenderTop);
+  path.lineTo(RenderRight, RenderBottom);
+  path.lineTo(RenderLeft, RenderCenterY);
+  path.lineTo(RenderRight, RenderCenterY);
+  path.lineTo(RenderLeft, RenderBottom);
+  path.close();
+  const SkColor color = SK_ColorDKGRAY;
+  const SkScalar elevation = 10;
+
+  CanvasCompareTester::RenderNoAttributes(
+      [=](SkCanvas* canvas, SkPaint& paint) {  //
+        PhysicalShapeLayer::DrawShadow(canvas, path, color, elevation, false,
+                                       2.5);
+      },
+      [=](DisplayListBuilder& builder) {  //
+        builder.drawShadow(path, color, elevation, false, 2.5);
       });
   CanvasCompareTester::UsingShadows = false;
 }

flow/display_list_unittests.cc

@@ -663,11 +663,12 @@ std::vector<DisplayListInvocationGroup> allGroups = {
   // See: https://bugs.chromium.org/p/skia/issues/detail?id=12125
   { "DrawShadow", {
       // cv shadows are turned into an opaque ShadowRec which is not exposed
-      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 1.0, false);}},
-      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath2, SK_ColorGREEN, 1.0, false);}},
-      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorBLUE, 1.0, false);}},
-      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 2.0, false);}},
-      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 1.0, true);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 1.0, false, 1.0);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath2, SK_ColorGREEN, 1.0, false, 1.0);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorBLUE, 1.0, false, 1.0);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 2.0, false, 1.0);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 1.0, true, 1.0);}},
+      {1, 32, -1, 32, [](DisplayListBuilder& b) {b.drawShadow(TestPath1, SK_ColorGREEN, 1.0, false, 2.5);}},
     }
   },
 };

flow/display_list_utils.cc

@@ -335,7 +335,8 @@ void DisplayListBoundsCalculator::drawTextBlob(const sk_sp<SkTextBlob> blob,
 void DisplayListBoundsCalculator::drawShadow(const SkPath& path,
                                              const SkColor color,
                                              const SkScalar elevation,
-                                             bool occludes) {
+                                             bool occludes,
+                                             SkScalar dpr) {
   // Constants from physical_shape_layer.cc
   const SkScalar kLightHeight = 600;
   const SkScalar kLightRadius = 800;
@@ -348,9 +349,9 @@ void DisplayListBoundsCalculator::drawShadow(const SkPath& path,
   SkScalar shadow_y = bounds.top() - 600.0f;
   SkRect shadow_bounds;
   SkShadowUtils::GetLocalBounds(
-      matrix(), path, SkPoint3::Make(0, 0, elevation),
-      SkPoint3::Make(shadow_x, shadow_y, kLightHeight), kLightRadius, flags,
-      &shadow_bounds);
+      matrix(), path, SkPoint3::Make(0, 0, dpr * elevation),
+      SkPoint3::Make(shadow_x, shadow_y, dpr * kLightHeight),
+      dpr * kLightRadius, flags, &shadow_bounds);
   accumulateRect(shadow_bounds);
 }
 

flow/display_list_utils.h

@@ -308,7 +308,8 @@ class DisplayListBoundsCalculator final
   void drawShadow(const SkPath& path,
                   const SkColor color,
                   const SkScalar elevation,
-                  bool occludes) override;
+                  bool occludes,
+                  SkScalar dpr) override;
 
   SkRect getBounds() { return accumulator_->getBounds(); }
 

lib/ui/painting/canvas.cc

@@ -499,6 +499,11 @@ void Canvas::drawShadow(const CanvasPath* path,
         ToDart("Canvas.drawShader called with non-genuine Path."));
     return;
   }
+  SkScalar dpr = UIDartState::Current()
+                     ->platform_configuration()
+                     ->get_window(0)
+                     ->viewport_metrics()
+                     .device_pixel_ratio;
   if (display_list_recorder_) {
     // The DrawShadow mechanism results in non-public operations to be
     // performed on the canvas involving an SkDrawShadowRec. Since we
@@ -507,13 +512,9 @@ void Canvas::drawShadow(const CanvasPath* path,
     // that situation we bypass the canvas interface and inject the
     // shadow parameters directly into the underlying DisplayList.
     // See: https://bugs.chromium.org/p/skia/issues/detail?id=12125
-    builder()->drawShadow(path->path(), color, elevation, transparentOccluder);
+    builder()->drawShadow(path->path(), color, elevation, transparentOccluder,
+                          dpr);
   } else {
-    SkScalar dpr = UIDartState::Current()
-                       ->platform_configuration()
-                       ->get_window(0)
-                       ->viewport_metrics()
-                       .device_pixel_ratio;
     flutter::PhysicalShapeLayer::DrawShadow(
         canvas_, path->path(), color, elevation, transparentOccluder, dpr);
   }