Fixed bookkeeping bug in management of dimensions of mailbox's texture.

Source/web/tests/DrawingBufferTest.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 16 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 
 #include "platform/graphics/gpu/DrawingBuffer.h"
 
 #include "platform/graphics/GraphicsContext3D.h"
 #include "public/platform/Platform.h"
+#include "public/platform/WebExternalTextureMailbox.h"
 #include "web/tests/MockWebGraphicsContext3D.h"
 #include "wtf/RefPtr.h"
 
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 using namespace WebCore;
 using namespace blink;
 using testing::Test;
 using testing::_;
 
 namespace {
 
 class FakeContextEvictionManager : public ContextEvictionManager {
 public:
     void forciblyLoseOldestContext(const String& reason) { }
     IntSize oldestContextSize() { return IntSize(); }
 };
 
+class WebGraphicsContext3DForTests : public MockWebGraphicsContext3D {
+public:
+    WebGraphicsContext3DForTests()
+        : MockWebGraphicsContext3D()
+        , m_boundTexture(0)
+        , m_currentMailboxByte(0) { }
+
+    virtual void bindTexture(WGC3Denum target, WebGLId texture)
+    {
+        if (target == GraphicsContext3D::TEXTURE_2D) {
+            m_boundTexture = texture;
+        }
+    }
+
+    virtual void texImage2D(WGC3Denum target, WGC3Dint level, WGC3Denum internalformat, WGC3Dsizei width, WGC3Dsizei height, WGC3Dint border, WGC3Denum format, WGC3Denum type, const void* pixels)
+    {
+        if (target == GraphicsContext3D::TEXTURE_2D && !level) {
+            m_textureSizes.set(m_boundTexture, IntSize(width, height));
+        }
+    }
+
+    virtual void genMailboxCHROMIUM(WGC3Dbyte* mailbox)
+    {
+        ++m_currentMailboxByte;
+        WebExternalTextureMailbox temp;
+        memset(mailbox, m_currentMailboxByte, sizeof(temp.name));
+    }
+
+    virtual void produceTextureCHROMIUM(WGC3Denum target, const WGC3Dbyte* mailbox)
+    {
+        ASSERT_EQ(target, GraphicsContext3D::TEXTURE_2D);
+        m_mostRecentlyProducedSize = m_textureSizes.get(m_boundTexture);
+    }
+
+    IntSize mostRecentlyProducedSize()
+    {
+        return m_mostRecentlyProducedSize;
+    }
+
+private:
+    WebGLId m_boundTexture;
+    HashMap<WebGLId, IntSize> m_textureSizes;
+    WGC3Dbyte m_currentMailboxByte;
+    IntSize m_mostRecentlyProducedSize;
+};
+
+static const int initialWidth = 100;
+static const int initialHeight = 100;
+static const int alternateHeight = 50;
+
 } // namespace
 
 class DrawingBufferTest : public Test {
 protected:
     virtual void SetUp()
     {
         RefPtr<FakeContextEvictionManager> contextEvictionManager = adoptRef(new FakeContextEvictionManager());
-        RefPtr<GraphicsContext3D> context = GraphicsContext3D::createGraphicsContextFromWebContext(adoptPtr(new MockWebGraphicsContext3D));
-        const IntSize size(100, 100);
-        m_drawingBuffer = DrawingBuffer::create(context.get(), size, DrawingBuffer::Discard, contextEvictionManager.release());
+        RefPtr<GraphicsContext3D> context = GraphicsContext3D::createGraphicsContextFromWebContext(adoptPtr(new WebGraphicsContext3DForTests));
+        m_drawingBuffer = DrawingBuffer::create(context.get(), IntSize(initialWidth, initialHeight), DrawingBuffer::Discard, contextEvictionManager.release());
+    }
+
+    WebGraphicsContext3DForTests* webContext()
+    {
+        return static_cast<WebGraphicsContext3DForTests*>(m_drawingBuffer->context());
     }
 
     RefPtr<DrawingBuffer> m_drawingBuffer;
 };
 
 namespace {
 
 TEST_F(DrawingBufferTest, verifyNoNewBuffersAfterContextLostWithMailboxes)
 {
     // Tell the buffer its contents changed and context was lost.
     m_drawingBuffer->markContentsChanged();
     m_drawingBuffer->releaseResources();
 
     blink::WebExternalTextureMailbox mailbox;
     EXPECT_FALSE(m_drawingBuffer->prepareMailbox(&mailbox, 0));
 }
 
+TEST_F(DrawingBufferTest, verifyResizingProperlyAffectsMailboxes)
+{
+    blink::WebExternalTextureMailbox mailbox;
+
+    IntSize initialSize(initialWidth, initialHeight);
+    IntSize alternateSize(initialWidth, alternateHeight);
+
+    // Produce one mailbox at size 100x100.
+    m_drawingBuffer->markContentsChanged();
+    EXPECT_TRUE(m_drawingBuffer->prepareMailbox(&mailbox, 0));
+    EXPECT_EQ(initialSize, webContext()->mostRecentlyProducedSize());
+
+    // Resize to 100x50.
+    m_drawingBuffer->reset(IntSize(initialWidth, alternateHeight));
+    m_drawingBuffer->mailboxReleased(mailbox);
+
+    // Produce a mailbox at this size.
+    m_drawingBuffer->markContentsChanged();
+    EXPECT_TRUE(m_drawingBuffer->prepareMailbox(&mailbox, 0));
+    EXPECT_EQ(alternateSize, webContext()->mostRecentlyProducedSize());
+
+    // Reset to initial size.
+    m_drawingBuffer->reset(IntSize(initialWidth, initialHeight));
+    m_drawingBuffer->mailboxReleased(mailbox);
+
+    // Prepare another mailbox and verify that it's the correct size.
+    m_drawingBuffer->markContentsChanged();
+    EXPECT_TRUE(m_drawingBuffer->prepareMailbox(&mailbox, 0));
+    EXPECT_EQ(initialSize, webContext()->mostRecentlyProducedSize());
+
+    // Prepare one final mailbox and verify that it's the correct size.
+    m_drawingBuffer->mailboxReleased(mailbox);
+    m_drawingBuffer->markContentsChanged();
+    EXPECT_TRUE(m_drawingBuffer->prepareMailbox(&mailbox, 0));
+    EXPECT_EQ(initialSize, webContext()->mostRecentlyProducedSize());
+}
+
 } // namespace