Mark layers that can use LCD text based on layer transform and opacity.

cc/content_layer_unittest.cc

 // Copyright 2012 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/content_layer.h"
 
 #include "cc/bitmap_content_layer_updater.h"
 #include "cc/content_layer_client.h"
 #include "cc/rendering_stats.h"
+#include "cc/resource_update_queue.h"
 #include "cc/test/geometry_test_utils.h"
 #include "skia/ext/platform_canvas.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/rect_conversions.h"
 
 using namespace WebKit;
 
 namespace cc {
 namespace {
 
+class FakeContentLayer : public ContentLayer {
+public:
+    explicit FakeContentLayer(ContentLayerClient* client) : ContentLayer(client) { }
+
+protected:
+    virtual ~FakeContentLayer() { }
+    virtual void createUpdaterIfNeeded() OVERRIDE { }
+};
+
 class MockContentLayerClient : public ContentLayerClient {
 public:
     explicit MockContentLayerClient(gfx::Rect opaqueLayerRect)
         : m_opaqueLayerRect(opaqueLayerRect)
     {
     }
 
     virtual void paintContents(SkCanvas*, const gfx::Rect&, gfx::RectF& opaque) OVERRIDE
     {
         opaque = gfx::RectF(m_opaqueLayerRect);
@@ skipping 12 matching lines @@
     MockContentLayerClient client(opaqueRectInLayerSpace);
     scoped_refptr<BitmapContentLayerUpdater> updater = BitmapContentLayerUpdater::create(ContentLayerPainter::create(&client).PassAs<LayerPainter>());
 
     gfx::Rect resultingOpaqueRect;
     RenderingStats stats;
     updater->prepareToUpdate(contentRect, gfx::Size(256, 256), contentsScale, contentsScale, resultingOpaqueRect, stats);
 
     EXPECT_RECT_EQ(gfx::ToEnclosingRect(opaqueRectInContentSpace), resultingOpaqueRect);
 }
 
+TEST(ContentLayerTest, CanUseLCDTextEnableCount)
+{
+    scoped_refptr<FakeContentLayer> layer = new FakeContentLayer(NULL);
+
+    // By default LCD text is disabled.
+    EXPECT_FALSE(layer->canUseLCDText());
+
+    // LCD text can be enabled once.
+    layer->setCanUseLCDText(true);
+    EXPECT_TRUE(layer->canUseLCDText());
+
+    // LCD text can always be disabled.
+    layer->setCanUseLCDText(false);
+    EXPECT_FALSE(layer->canUseLCDText());
+
+    // LCD text cannot be enabled anymore.
+    layer->setCanUseLCDText(true);
+    EXPECT_FALSE(layer->canUseLCDText());
+}
+
+TEST(ContentLayerTest, CanUseLCDTextChangeTriggersRepaint)
+{
+    scoped_refptr<FakeContentLayer> layer = new FakeContentLayer(NULL);
+    layer->setBounds(gfx::Size(100, 100));
+    ResourceUpdateQueue queue;
+    RenderingStats stats;
+    // Reset needsDisplay bit.
+    layer->update(queue, NULL, stats);
+    EXPECT_FALSE(layer->canUseLCDText());
+    EXPECT_FALSE(layer->needsDisplay());
+
+    layer->setCanUseLCDText(true);
+    EXPECT_TRUE(layer->canUseLCDText());
+    EXPECT_TRUE(layer->needsDisplay());
+
+    // Reset needsDisplay bit.
+    layer->update(queue, NULL, stats);
+    EXPECT_FALSE(layer->needsDisplay());
+
+    layer->setCanUseLCDText(false);
+    EXPECT_FALSE(layer->canUseLCDText());
+    EXPECT_TRUE(layer->needsDisplay());
+}
+
 }  // namespace
 }  // namespace cc