Back PaintRecord with PaintOpBuffer instead of SkPicture

cc/paint/paint_op_buffer_unittest.cc

Index: cc/paint/paint_op_buffer_unittest.cc
diff --git a/cc/paint/paint_op_buffer_unittest.cc b/cc/paint/paint_op_buffer_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e0b0171c17e62aa94f9a7f07094a57c9b3bb17e7
--- /dev/null
+++ b/cc/paint/paint_op_buffer_unittest.cc
@@ -0,0 +1,244 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cc/paint/paint_op_buffer.h"
+#include "cc/paint/test_skcanvas.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace cc {
+
+TEST(PaintOpBufferTest, Empty) {
+  PaintOpBuffer buffer;
+  EXPECT_EQ(buffer.approximateOpCount(), 0);
+  EXPECT_EQ(buffer.approximateBytesUsed(), sizeof(PaintOpBuffer));
+  EXPECT_EQ(PaintOpBuffer::Iterator(&buffer), false);
+
+  buffer.Reset();
+  EXPECT_EQ(buffer.approximateOpCount(), 0);
+  EXPECT_EQ(buffer.approximateBytesUsed(), sizeof(PaintOpBuffer));
+  EXPECT_EQ(PaintOpBuffer::Iterator(&buffer), false);
+}
+
+TEST(PaintOpBufferTest, SimpleAppend) {
+  SkRect rect = SkRect::MakeXYWH(2, 3, 4, 5);
+  PaintFlags flags;
+  flags.setColor(SK_ColorMAGENTA);
+  flags.setAlpha(100);
+  SkColor draw_color = SK_ColorRED;
+  SkBlendMode blend = SkBlendMode::kSrc;
+
+  PaintOpBuffer buffer;
+  buffer.push<SaveLayerOp>(&rect, &flags);
+  buffer.push<SaveOp>();
+  buffer.push<DrawColorOp>(draw_color, blend);
+  buffer.push<RestoreOp>();
+
+  EXPECT_EQ(buffer.approximateOpCount(), 4);
+
+  PaintOpBuffer::Iterator iter(&buffer);
+  ASSERT_EQ(iter->GetType(), PaintOpType::SaveLayer);
+  SaveLayerOp* save_op = static_cast<SaveLayerOp*>(*iter);
+  EXPECT_EQ(save_op->bounds, rect);
+  EXPECT_TRUE(save_op->flags == flags);
+  ++iter;
+
+  ASSERT_EQ(iter->GetType(), PaintOpType::Save);
+  ++iter;
+
+  ASSERT_EQ(iter->GetType(), PaintOpType::DrawColor);
+  DrawColorOp* op = static_cast<DrawColorOp*>(*iter);
+  EXPECT_EQ(op->color, draw_color);
+  EXPECT_EQ(op->mode, blend);
+  ++iter;
+
+  ASSERT_EQ(iter->GetType(), PaintOpType::Restore);
+  ++iter;
+
+  EXPECT_FALSE(iter);
+}
+
+// PaintOpBuffer has a special case for first ops stored locally, so
+// make sure that appending different kind of ops as a first op works
+// properly, as well as resetting and reusing the first local op.
+TEST(PaintOpBufferTest, FirstOpWithAndWithoutData) {
+  PaintOpBuffer buffer;
+  char text[] = "asdf";
+
+  // Use a color filter and its ref count to verify that the destructor
+  // is called on ops after reset.
+  PaintFlags flags;
+  sk_sp<SkColorFilter> filter =
+      SkColorFilter::MakeModeFilter(SK_ColorMAGENTA, SkBlendMode::kSrcOver);
+  flags.setColorFilter(filter);
+  EXPECT_EQ(filter->getRefCnt(), 2);
+
+  buffer.push_with_data<DrawTextOp>(text, arraysize(text), 0.f, 0.f, flags);
+  EXPECT_EQ(filter->getRefCnt(), 3);
+
+  // Verify that when the first op has data, which may not fit in the
+  // PaintRecord internal buffer, that it adds a noop as the first op
+  // and then appends the "op with data" into the heap buffer.
+  ASSERT_EQ(buffer.approximateOpCount(), 2);
+  EXPECT_EQ(buffer.GetFirstOp()->GetType(), PaintOpType::Noop);
+
+  // Verify iteration behavior and brief smoke test of op state.
+  {
+    PaintOpBuffer::Iterator iter(&buffer);
+    PaintOp* noop = *iter;
+    EXPECT_EQ(buffer.GetFirstOp(), noop);
+    ++iter;
+
+    PaintOp* op = *iter;
+    ASSERT_EQ(op->GetType(), PaintOpType::DrawText);
+    DrawTextOp* draw_text_op = static_cast<DrawTextOp*>(op);
+    EXPECT_EQ(draw_text_op->bytes, arraysize(text));
+
+    void* data = paint_op_data(draw_text_op);
+    EXPECT_EQ(memcmp(data, text, arraysize(text)), 0);
+
+    ++iter;
+    EXPECT_FALSE(iter);
+  }
+
+  // Reset, verify state, and append an op that will fit in the first slot.
+  buffer.Reset();
+  EXPECT_EQ(filter->getRefCnt(), 2);
+
+  ASSERT_EQ(buffer.approximateOpCount(), 0);
+  EXPECT_EQ(PaintOpBuffer::Iterator(&buffer), false);
+
+  SkRect rect = SkRect::MakeXYWH(1, 2, 3, 4);
+  buffer.push<DrawRectOp>(rect, flags);
+  EXPECT_EQ(filter->getRefCnt(), 3);
+
+  ASSERT_EQ(buffer.approximateOpCount(), 1);
+  EXPECT_EQ(buffer.GetFirstOp()->GetType(), PaintOpType::DrawRect);
+
+  PaintOpBuffer::Iterator iter(&buffer);
+  ASSERT_EQ(iter->GetType(), PaintOpType::DrawRect);
+  DrawRectOp* draw_rect_op = static_cast<DrawRectOp*>(*iter);
+  EXPECT_EQ(draw_rect_op->rect, rect);
+
+  ++iter;
+  EXPECT_FALSE(iter);
+
+  buffer.Reset();
+  ASSERT_EQ(buffer.approximateOpCount(), 0);
+  EXPECT_EQ(filter->getRefCnt(), 2);
+}
+
+TEST(PaintOpBufferTest, Peek) {
+  PaintOpBuffer buffer;
+
+  uint8_t alpha = 100;
+  buffer.push<SaveLayerAlphaOp>(nullptr, alpha);
+  PaintFlags draw_flags;
+  buffer.push<DrawRectOp>(SkRect::MakeXYWH(1, 2, 3, 4), draw_flags);
+  buffer.push<RestoreOp>();
+  buffer.push<SaveOp>();
+  buffer.push<NoopOp>();
+  buffer.push<RestoreOp>();
+
+  PaintOpBuffer::Iterator init_iter(&buffer);
+  PaintOp* peek[2] = {*init_iter, init_iter.peek1()};
+
+  // Expect that while iterating that next = current.peek1() and that
+  // next.peek1() == current.peek2().
+  for (PaintOpBuffer::Iterator iter(&buffer); iter; ++iter) {
+    EXPECT_EQ(*iter, peek[0]) << iter.op_idx();
+    EXPECT_EQ(iter.peek1(), peek[1]) << iter.op_idx();
+
+    peek[0] = iter.peek1();
+    peek[1] = iter.peek2();
+  }
+}
+
+TEST(PaintOpBufferTest, PeekEmpty) {
+  PaintOpBuffer empty;
+  PaintOpBuffer::Iterator empty_iter(&empty);
+  EXPECT_EQ(nullptr, empty_iter.peek1());
+  EXPECT_EQ(nullptr, empty_iter.peek2());
+}
+
+// Verify that a SaveLayerAlpha / Draw / Restore can be optimized to just
+// a draw with opacity.
+TEST(PaintOpBufferTest, SaveDrawRestore) {
+  PaintOpBuffer buffer;
+
+  uint8_t alpha = 100;
+  buffer.push<SaveLayerAlphaOp>(nullptr, alpha);
+
+  PaintFlags draw_flags;
+  draw_flags.setColor(SK_ColorMAGENTA);
+  draw_flags.setAlpha(50);
+  EXPECT_TRUE(draw_flags.SupportsFoldingAlpha());
+  SkRect rect = SkRect::MakeXYWH(1, 2, 3, 4);
+  buffer.push<DrawRectOp>(rect, draw_flags);
+  buffer.push<RestoreOp>();
+
+  SaveCountingCanvas canvas;
+  buffer.playback(&canvas);
+
+  EXPECT_EQ(0, canvas.restore_count_);
+  EXPECT_EQ(rect, canvas.draw_rect_);
+
+  // Expect the alpha from the draw and the save layer to be folded together.
+  // Since alpha is stored in a uint8_t and gets rounded, so use tolerance.
+  float expected_alpha = alpha * 50 / 255.f;
+  EXPECT_LE(std::abs(expected_alpha - canvas.paint_.getAlpha()), 1.f);
+}
+
+// The same as SaveDrawRestore, but test that the optimization doesn't apply
+// when the drawing op's flags are not compatible with being folded into the
+// save layer with opacity.
+TEST(PaintOpBufferTest, SaveDrawRestoreFail_BadFlags) {
+  PaintOpBuffer buffer;
+
+  uint8_t alpha = 100;
+  buffer.push<SaveLayerAlphaOp>(nullptr, alpha);
+
+  PaintFlags draw_flags;
+  draw_flags.setColor(SK_ColorMAGENTA);
+  draw_flags.setAlpha(50);
+  draw_flags.setBlendMode(SkBlendMode::kSrc);
+  EXPECT_FALSE(draw_flags.SupportsFoldingAlpha());
+  SkRect rect = SkRect::MakeXYWH(1, 2, 3, 4);
+  buffer.push<DrawRectOp>(rect, draw_flags);
+  buffer.push<RestoreOp>();
+
+  SaveCountingCanvas canvas;
+  buffer.playback(&canvas);
+
+  EXPECT_EQ(1, canvas.restore_count_);
+  EXPECT_EQ(rect, canvas.draw_rect_);
+  EXPECT_EQ(draw_flags.getAlpha(), canvas.paint_.getAlpha());
+}
+
+// The same as SaveDrawRestore, but test that the optimization doesn't apply
+// when there are more than one ops between the save and restore.
+TEST(PaintOpBufferTest, SaveDrawRestoreFail_TooManyOps) {
+  PaintOpBuffer buffer;
+
+  uint8_t alpha = 100;
+  buffer.push<SaveLayerAlphaOp>(nullptr, alpha);
+
+  PaintFlags draw_flags;
+  draw_flags.setColor(SK_ColorMAGENTA);
+  draw_flags.setAlpha(50);
+  draw_flags.setBlendMode(SkBlendMode::kSrcOver);
+  EXPECT_TRUE(draw_flags.SupportsFoldingAlpha());
+  SkRect rect = SkRect::MakeXYWH(1, 2, 3, 4);
+  buffer.push<DrawRectOp>(rect, draw_flags);
+  buffer.push<NoopOp>();
+  buffer.push<RestoreOp>();
+
+  SaveCountingCanvas canvas;
+  buffer.playback(&canvas);
+
+  EXPECT_EQ(1, canvas.restore_count_);
+  EXPECT_EQ(rect, canvas.draw_rect_);
+  EXPECT_EQ(draw_flags.getAlpha(), canvas.paint_.getAlpha());
+}
+
+}  // namespace cc