cc: Add PaintCanvas::clipDeviceRect

Instead of having to serialize SkRegion (as clipRegion is the only call
that needs a region), instead add a top level "clip device rect" that
takes two parameters.  This is to support the use case that the
RasterSource canvas setup preamble uses to clear the canvas efficiently.

Bug: 737629
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Icfb41557c716d5c52ef44454b8791e29c36d5bda
Reviewed-on: https://chromium-review.googlesource.com/590950Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Vladimir Levin <vmpstr@chromium.org>
Commit-Queue: enne <enne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491159}

cc/paint/paint_canvas.h

@@ -85,6 +85,11 @@ class CC_PAINT_EXPORT PaintCanvas {
   void clipPath(const SkPath& path, bool do_anti_alias) {
     clipPath(path, SkClipOp::kIntersect, do_anti_alias);
   }
+  // Clip a |device_rect| in canvas device space (subtracting out the
+  // |subtract_rect|, if non-empty, from that rect).
+  virtual void clipDeviceRect(const SkIRect& device_rect,
+                              const SkIRect& subtract_rect,
+                              SkClipOp op) = 0;
 
   virtual bool quickReject(const SkRect& rect) const = 0;
   virtual bool quickReject(const SkPath& path) const = 0;

cc/paint/paint_op_buffer.cc

@@ -14,6 +14,7 @@
 #include "cc/paint/paint_record.h"
 #include "third_party/skia/include/core/SkAnnotation.h"
 #include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkRegion.h"
 
 namespace cc {
 namespace {
@@ -165,6 +166,7 @@ void RasterWithAlpha(const PaintOp* op,
 
 #define TYPES(M)      \
   M(AnnotateOp)       \
+  M(ClipDeviceRectOp) \
   M(ClipPathOp)       \
   M(ClipRectOp)       \
   M(ClipRRectOp)      \
@@ -327,6 +329,8 @@ std::string PaintOpTypeToString(PaintOpType type) {
   switch (type) {
     case PaintOpType::Annotate:
       return "Annotate";
+    case PaintOpType::ClipDeviceRect:
+      return "ClipDeviceRect";
     case PaintOpType::ClipPath:
       return "ClipPath";
     case PaintOpType::ClipRect:
@@ -413,6 +417,13 @@ size_t AnnotateOp::Serialize(const PaintOp* base_op,
   return helper.size();
 }
 
+size_t ClipDeviceRectOp::Serialize(const PaintOp* op,
+                                   void* memory,
+                                   size_t size,
+                                   const SerializeOptions& options) {
+  return SimpleSerialize<ClipDeviceRectOp>(op, memory, size);
+}
+
 size_t ClipPathOp::Serialize(const PaintOp* base_op,
                              void* memory,
                              size_t size,
@@ -748,6 +759,14 @@ PaintOp* AnnotateOp::Deserialize(const void* input,
   return op;
 }
 
+PaintOp* ClipDeviceRectOp::Deserialize(const void* input,
+                                       size_t input_size,
+                                       void* output,
+                                       size_t output_size) {
+  return SimpleDeserialize<ClipDeviceRectOp>(input, input_size, output,
+                                             output_size);
+}
+
 PaintOp* ClipPathOp::Deserialize(const void* input,
                                  size_t input_size,
                                  void* output,
@@ -1195,6 +1214,16 @@ void AnnotateOp::Raster(const AnnotateOp* op,
   }
 }
 
+void ClipDeviceRectOp::Raster(const ClipDeviceRectOp* op,
+                              SkCanvas* canvas,
+                              const PlaybackParams& params) {
+  SkRegion device_region;
+  device_region.setRect(op->device_rect);
+  if (!op->subtract_rect.isEmpty())
+    device_region.op(op->subtract_rect, SkRegion::kDifference_Op);
+  canvas->clipRegion(device_region, op->op);
+}
+
 void ClipPathOp::Raster(const ClipPathOp* op,
                         SkCanvas* canvas,
                         const PlaybackParams& params) {

cc/paint/paint_op_buffer.h

@@ -57,6 +57,7 @@ class CC_PAINT_EXPORT ThreadsafePath : public SkPath {
 
 enum class PaintOpType : uint8_t {
   Annotate,
+  ClipDeviceRect,
   ClipPath,
   ClipRect,
   ClipRRect,
@@ -342,6 +343,23 @@ class CC_PAINT_EXPORT AnnotateOp final : public PaintOp {
   AnnotateOp();
 };
 
+class CC_PAINT_EXPORT ClipDeviceRectOp final : public PaintOp {
+ public:
+  static constexpr PaintOpType kType = PaintOpType::ClipDeviceRect;
+  ClipDeviceRectOp(const SkIRect& device_rect,
+                   const SkIRect& subtract_rect,
+                   SkClipOp op)
+      : device_rect(device_rect), subtract_rect(subtract_rect), op(op) {}
+  static void Raster(const ClipDeviceRectOp* op,
+                     SkCanvas* canvas,
+                     const PlaybackParams& params);
+  HAS_SERIALIZATION_FUNCTIONS();
+
+  SkIRect device_rect;
+  SkIRect subtract_rect;
+  SkClipOp op;
+};
+
 class CC_PAINT_EXPORT ClipPathOp final : public PaintOp {
  public:
   static constexpr PaintOpType kType = PaintOpType::ClipPath;

cc/paint/paint_op_buffer_unittest.cc

@@ -1360,6 +1360,13 @@ void PushAnnotateOps(PaintOpBuffer* buffer) {
                            test_rects[2], SkData::MakeEmpty());
 }
 
+void PushClipDeviceRectOps(PaintOpBuffer* buffer) {
+  for (size_t i = 1; i < test_irects.size(); i += 2) {
+    SkClipOp op = i % 3 ? SkClipOp::kDifference : SkClipOp::kIntersect;
+    buffer->push<ClipDeviceRectOp>(test_irects[i - 1], test_irects[0], op);
+  }
+}
+
 void PushClipPathOps(PaintOpBuffer* buffer) {
   for (size_t i = 0; i < test_paths.size(); ++i) {
     SkClipOp op = i % 3 ? SkClipOp::kDifference : SkClipOp::kIntersect;
@@ -1601,6 +1608,13 @@ void CompareAnnotateOp(const AnnotateOp* original, const AnnotateOp* written) {
   }
 }
 
+void CompareClipDeviceRectOp(const ClipDeviceRectOp* original,
+                             const ClipDeviceRectOp* written) {
+  EXPECT_EQ(original->device_rect, written->device_rect);
+  EXPECT_EQ(original->subtract_rect, written->subtract_rect);
+  EXPECT_EQ(original->op, written->op);
+}
+
 void CompareClipPathOp(const ClipPathOp* original, const ClipPathOp* written) {
   EXPECT_TRUE(original->path == written->path);
   EXPECT_EQ(original->op, written->op);
@@ -1813,6 +1827,9 @@ class PaintOpSerializationTest : public ::testing::TestWithParam<uint8_t> {
       case PaintOpType::Annotate:
         PushAnnotateOps(&buffer_);
         break;
+      case PaintOpType::ClipDeviceRect:
+        PushClipDeviceRectOps(&buffer_);
+        break;
       case PaintOpType::ClipPath:
         PushClipPathOps(&buffer_);
         break;
@@ -1914,6 +1931,10 @@ class PaintOpSerializationTest : public ::testing::TestWithParam<uint8_t> {
         CompareAnnotateOp(static_cast<const AnnotateOp*>(original),
                           static_cast<const AnnotateOp*>(written));
         break;
+      case PaintOpType::ClipDeviceRect:
+        CompareClipDeviceRectOp(static_cast<const ClipDeviceRectOp*>(original),
+                                static_cast<const ClipDeviceRectOp*>(written));
+        break;
       case PaintOpType::ClipPath:
         CompareClipPathOp(static_cast<const ClipPathOp*>(original),
                           static_cast<const ClipPathOp*>(written));

cc/paint/record_paint_canvas.cc

@@ -164,6 +164,12 @@ void RecordPaintCanvas::clipPath(const SkPath& path,
   return;
 }
 
+void RecordPaintCanvas::clipDeviceRect(const SkIRect& device_rect,
+                                       const SkIRect& subtract_rect,
+                                       SkClipOp op) {
+  list_->push<ClipDeviceRectOp>(device_rect, subtract_rect, op);
+}
+
 bool RecordPaintCanvas::quickReject(const SkRect& rect) const {
   return GetCanvas()->quickReject(rect);
 }

cc/paint/record_paint_canvas.h

@@ -50,6 +50,9 @@ class CC_PAINT_EXPORT RecordPaintCanvas final : public PaintCanvas {
   void clipRect(const SkRect& rect, SkClipOp op, bool antialias) override;
   void clipRRect(const SkRRect& rrect, SkClipOp op, bool antialias) override;
   void clipPath(const SkPath& path, SkClipOp op, bool antialias) override;
+  void clipDeviceRect(const SkIRect& device_rect,
+                      const SkIRect& subtract_rect,
+                      SkClipOp op) override;
   bool quickReject(const SkRect& rect) const override;
   bool quickReject(const SkPath& path) const override;
   SkRect getLocalClipBounds() const override;

cc/paint/skia_paint_canvas.cc

@@ -10,6 +10,7 @@
 #include "third_party/skia/include/core/SkAnnotation.h"
 #include "third_party/skia/include/core/SkColorSpaceXformCanvas.h"
 #include "third_party/skia/include/core/SkMetaData.h"
+#include "third_party/skia/include/core/SkRegion.h"
 #include "third_party/skia/include/utils/SkNWayCanvas.h"
 
 namespace cc {
@@ -156,6 +157,16 @@ void SkiaPaintCanvas::clear(SkColor color) {
   canvas_->clear(color);
 }
 
+void SkiaPaintCanvas::clipDeviceRect(const SkIRect& device_rect,
+                                     const SkIRect& subtract_rect,
+                                     SkClipOp op) {
+  SkRegion device_region;
+  device_region.setRect(device_rect);
+  if (!subtract_rect.isEmpty())
+    device_region.op(subtract_rect, SkRegion::kDifference_Op);
+  canvas_->clipRegion(device_region, op);
+}
+
 void SkiaPaintCanvas::drawLine(SkScalar x0,
                                SkScalar y0,
                                SkScalar x1,

cc/paint/skia_paint_canvas.h

@@ -58,6 +58,9 @@ class CC_PAINT_EXPORT SkiaPaintCanvas final : public PaintCanvas {
                  SkClipOp op,
                  bool do_anti_alias) override;
   void clipPath(const SkPath& path, SkClipOp op, bool do_anti_alias) override;
+  void clipDeviceRect(const SkIRect& device_rect,
+                      const SkIRect& subtract_rect,
+                      SkClipOp op) override;
   bool quickReject(const SkRect& rect) const override;
   bool quickReject(const SkPath& path) const override;
   SkRect getLocalClipBounds() const override;

cc/paint/solid_color_analyzer.cc

@@ -235,6 +235,20 @@ base::Optional<SkColor> SolidColorAnalyzer::DetermineIfSolidColor(
         op->Raster(&canvas, params);
         break;
       }
+      case PaintOpType::ClipDeviceRect: {
+        // Similar to the ClipRect comment above, if clipDeviceRect uses
+        // a difference op or has an implicit subtraction (which would
+        // create a non-rect), then this creates a non-rect clip and
+        // we assume non-solid color.
+        const ClipDeviceRectOp* clip_op =
+            static_cast<const ClipDeviceRectOp*>(op);
+        if (clip_op->op == SkClipOp::kDifference)
+          return base::nullopt;
+        if (!clip_op->subtract_rect.isEmpty())
+          return base::nullopt;
+        op->Raster(&canvas, params);
+        break;
+      }
 
       // The rest of the ops should only affect our state canvas.
       case PaintOpType::Annotate:

cc/paint/solid_color_analyzer_unittest.cc

@@ -152,6 +152,48 @@ TEST_F(SolidColorAnalyzerTest, DrawRectClippedDifference) {
   EXPECT_FALSE(IsSolidColor());
 }
 
+TEST_F(SolidColorAnalyzerTest, DrawRectClipRegionUnclipped) {
+  Initialize();
+  PaintFlags flags;
+  SkColor color = SkColorSetARGB(255, 11, 22, 33);
+  flags.setColor(color);
+  static constexpr int kTranslate = 3000;
+  canvas()->translate(kTranslate, kTranslate);
+  SkRect rect = SkRect::MakeXYWH(-kTranslate, -kTranslate, 100, 100);
+  // Clip exactly the device bounds.
+  canvas()->clipDeviceRect(SkIRect::MakeWH(100, 100), SkIRect::MakeEmpty(),
+                           SkClipOp::kIntersect);
+  canvas()->drawRect(rect, flags);
+  EXPECT_EQ(color, GetColor());
+}
+
+TEST_F(SolidColorAnalyzerTest, DrawRectClipRegionClipped) {
+  Initialize();
+  PaintFlags flags;
+  SkColor color = SkColorSetARGB(255, 11, 22, 33);
+  flags.setColor(color);
+  SkRect rect = SkRect::MakeWH(100, 100);
+  // Clip less than the device bounds.
+  canvas()->clipDeviceRect(SkIRect::MakeWH(50, 50), SkIRect::MakeEmpty(),
+                           SkClipOp::kIntersect);
+  canvas()->drawRect(rect, flags);
+  EXPECT_FALSE(IsSolidColor());
+}
+
+TEST_F(SolidColorAnalyzerTest, DrawRectClipRegionClipped2) {
+  Initialize();
+  PaintFlags flags;
+  SkColor color = SkColorSetARGB(255, 11, 22, 33);
+  flags.setColor(color);
+  SkRect rect = SkRect::MakeWH(100, 100);
+  // Clip a reverse L shape (100x100 with a 50x50 corner bite out of it).
+  // This should not be solid.
+  canvas()->clipDeviceRect(SkIRect::MakeWH(100, 100), SkIRect::MakeWH(50, 50),
+                           SkClipOp::kIntersect);
+  canvas()->drawRect(rect, flags);
+  EXPECT_FALSE(IsSolidColor());
+}
+
 TEST_F(SolidColorAnalyzerTest, DrawRectWithTranslateNotSolid) {
   Initialize();
   PaintFlags flags;

third_party/WebKit/Source/platform/graphics/test/MockPaintCanvas.h

@@ -33,6 +33,10 @@ class MockPaintCanvas : public PaintCanvas {
                void(const SkRRect& rrect, SkClipOp op, bool do_anti_alias));
   MOCK_METHOD3(clipPath,
                void(const SkPath& path, SkClipOp op, bool do_anti_alias));
+  MOCK_METHOD3(clipDeviceRect,
+               void(const SkIRect& device_rect,
+                    const SkIRect& subtract_rect,
+                    SkClipOp op));
   MOCK_CONST_METHOD1(quickReject, bool(const SkRect& rect));
   MOCK_CONST_METHOD1(quickReject, bool(const SkPath& path));
   MOCK_CONST_METHOD0(getLocalClipBounds, SkRect());