Fixes a bug when the framebuffer is cleared with invalid scissor rect.

BUG=170305

Review URL: https://chromiumcodereview.appspot.com/12036091

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@179498 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 82 insertions, 1 deletions

diff --git a/cc/direct_renderer.cc b/cc/direct_renderer.cc
index 31f48e5..f9fb233 100644
--- a/cc/direct_renderer.cc
+++ b/cc/direct_renderer.cc
@@ -240,8 +240,11 @@ void DirectRenderer::drawRenderPass(DrawingFrame& frame, const RenderPass* rende
         setScissorTestRect(moveScissorToWindowSpace(frame, renderPassScissor));
     }
 
-    if (frame.currentRenderPass != frame.rootRenderPass || m_client->shouldClearRootRenderPass())
+    if (frame.currentRenderPass != frame.rootRenderPass || m_client->shouldClearRootRenderPass()) {
+        if (!usingScissorAsOptimization)
+            ensureScissorTestDisabled();
         clearFramebuffer(frame);
+    }
 
     const QuadList& quadList = renderPass->quad_list;
     for (QuadList::constBackToFrontIterator it = quadList.backToFrontBegin(); it != quadList.backToFrontEnd(); ++it) {
diff --git a/cc/gl_renderer_unittest.cc b/cc/gl_renderer_unittest.cc
index 89603b1..e9665ab 100644
--- a/cc/gl_renderer_unittest.cc
+++ b/cc/gl_renderer_unittest.cc
@@ -636,5 +636,63 @@ TEST(GLRendererTest2, shouldClearRootRenderPass)
     Mock::VerifyAndClearExpectations(&mockContext);
 }
 
+class ScissorTestOnClearCheckingContext : public FakeWebGraphicsContext3D {
+public:
+    ScissorTestOnClearCheckingContext() : m_scissorEnabled(false) { }
+
+    virtual void clear(WGC3Dbitfield)
+    {
+        EXPECT_FALSE(m_scissorEnabled);
+    }
+
+    virtual void enable(WGC3Denum cap)
+    {
+        if (cap == GL_SCISSOR_TEST)
+            m_scissorEnabled = true;
+    }
+
+    virtual void disable(WGC3Denum cap)
+    {
+        if (cap == GL_SCISSOR_TEST)
+            m_scissorEnabled = false;
+    }
+
+private:
+    bool m_scissorEnabled;
+};
+
+TEST(GLRendererTest2, scissorTestWhenClearing) {
+    FakeRendererClient mockClient;
+    scoped_ptr<OutputSurface> outputSurface(FakeOutputSurface::Create3d(scoped_ptr<WebKit::WebGraphicsContext3D>(new ScissorTestOnClearCheckingContext)));
+    scoped_ptr<ResourceProvider> resourceProvider(ResourceProvider::create(outputSurface.get()));
+    FakeRendererGL renderer(&mockClient, outputSurface.get(), resourceProvider.get());
+    EXPECT_TRUE(renderer.initialize());
+    EXPECT_FALSE(renderer.capabilities().usingPartialSwap);
+
+    gfx::Rect viewportRect(mockClient.deviceViewportSize());
+    ScopedPtrVector<RenderPass>& renderPasses = mockClient.renderPassesInDrawOrder();
+    renderPasses.clear();
+
+    gfx::Rect grandChildRect(25, 25);
+    RenderPass::Id grandChildPassId(3, 0);
+    TestRenderPass* grandChildPass = addRenderPass(renderPasses, grandChildPassId, grandChildRect, gfx::Transform());
+    addClippedQuad(grandChildPass, grandChildRect, SK_ColorYELLOW);
+
+    gfx::Rect childRect(50, 50);
+    RenderPass::Id childPassId(2, 0);
+    TestRenderPass* childPass = addRenderPass(renderPasses, childPassId, childRect, gfx::Transform());
+    addQuad(childPass, childRect, SK_ColorBLUE);
+
+    RenderPass::Id rootPassId(1, 0);
+    TestRenderPass* rootPass = addRenderPass(renderPasses, rootPassId, viewportRect, gfx::Transform());
+    addQuad(rootPass, viewportRect, SK_ColorGREEN);
+
+    addRenderPassQuad(rootPass, childPass);
+    addRenderPassQuad(childPass, grandChildPass);
+
+    renderer.decideRenderPassAllocationsForFrame(mockClient.renderPassesInDrawOrder());
+    renderer.drawFrame(mockClient.renderPassesInDrawOrder());
+}
+
 }  // namespace
 }  // namespace cc
diff --git a/cc/test/render_pass_test_utils.cc b/cc/test/render_pass_test_utils.cc
index b9f1217..bda83dd 100644
--- a/cc/test/render_pass_test_utils.cc
+++ b/cc/test/render_pass_test_utils.cc
@@ -41,6 +41,21 @@ SolidColorDrawQuad* addQuad(TestRenderPass* pass,
   return quadPtr;
 }
 
+SolidColorDrawQuad* addClippedQuad(TestRenderPass* pass,
+                                   const gfx::Rect& rect,
+                                   SkColor color) {
+  MockQuadCuller quadSink(pass->quad_list, pass->shared_quad_state_list);
+  AppendQuadsData data(pass->id);
+  SharedQuadState* sharedState =
+      quadSink.useSharedQuadState(SharedQuadState::Create());
+  sharedState->SetAll(gfx::Transform(), rect, rect, true, 1);
+  scoped_ptr<SolidColorDrawQuad> quad = SolidColorDrawQuad::Create();
+  quad->SetNew(sharedState, rect, color);
+  SolidColorDrawQuad* quadPtr = quad.get();
+  quadSink.append(quad.PassAs<DrawQuad>(), data);
+  return quadPtr;
+}
+
 void addRenderPassQuad(TestRenderPass* toPass,
                        TestRenderPass* contributingPass) {
   MockQuadCuller quadSink(toPass->quad_list, toPass->shared_quad_state_list);
diff --git a/cc/test/render_pass_test_utils.h b/cc/test/render_pass_test_utils.h
index b4d8dba..d9c2c91 100644
--- a/cc/test/render_pass_test_utils.h
+++ b/cc/test/render_pass_test_utils.h
@@ -32,6 +32,11 @@ SolidColorDrawQuad* addQuad(TestRenderPass* pass,
                             const gfx::Rect& rect,
                             SkColor color);
 
+// Adds a solid quad to a given render pass and sets is_clipped=true.
+SolidColorDrawQuad* addClippedQuad(TestRenderPass* pass,
+                                   const gfx::Rect& rect,
+                                   SkColor color);
+
 // Adds a render pass quad to an existing render pass.
 void addRenderPassQuad(TestRenderPass* toPass,
                        TestRenderPass* contributingPass);