Rebind to correct backbuffer after clearing READ buffer.

BUG=none
TEST=unit tests

R=jbates@chromium.org


Review URL: http://codereview.chromium.org/8756001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@112394 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 141 insertions, 22 deletions

diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index e2d60da..3de264c 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -3979,10 +3979,11 @@ void GLES2DecoderImpl::ClearUnclearedAttachments(
 
   if (target == GL_READ_FRAMEBUFFER_EXT) {
     glBindFramebufferEXT(GL_READ_FRAMEBUFFER_EXT, info->service_id());
-    FramebufferManager::FramebufferInfo*framebuffer =
-        GetFramebufferInfoForTarget(GL_READ_FRAMEBUFFER);
-    glBindFramebufferEXT(
-        GL_DRAW_FRAMEBUFFER_EXT, framebuffer ? framebuffer->service_id() : 0);
+    FramebufferManager::FramebufferInfo* framebuffer =
+        GetFramebufferInfoForTarget(GL_DRAW_FRAMEBUFFER_EXT);
+    GLuint service_id =
+        framebuffer ? framebuffer->service_id() : GetBackbufferServiceId();
+    glBindFramebufferEXT(GL_DRAW_FRAMEBUFFER_EXT, service_id);
   }
 }
 
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
index 25d96c7..9e587be 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
@@ -5459,6 +5459,66 @@ TEST_F(GLES2DecoderWithShaderTest, UnClearedAttachmentsGetClearedOnReadPixels) {
   EXPECT_EQ(GL_NO_ERROR, GetGLError());
 }
 
+TEST_F(GLES2DecoderManualInitTest,
+       UnClearedAttachmentsGetClearedOnReadPixelsAndDrawBufferGetsRestored) {
+  InitDecoder(
+      "GL_EXT_framebuffer_multisample",  // extensions
+      false,   // has alpha
+      false,   // has depth
+      false,   // has stencil
+      false,   // request alpha
+      false,   // request depth
+      false,   // request stencil
+      true);   // bind generates resource
+  const GLuint kFBOClientTextureId = 4100;
+  const GLuint kFBOServiceTextureId = 4101;
+
+  // Register a texture id.
+  EXPECT_CALL(*gl_, GenTextures(_, _))
+      .WillOnce(SetArgumentPointee<1>(kFBOServiceTextureId))
+      .RetiresOnSaturation();
+  GenHelper<GenTexturesImmediate>(kFBOClientTextureId);
+
+  // Setup "render from" texture.
+  DoBindTexture(GL_TEXTURE_2D, kFBOClientTextureId, kFBOServiceTextureId);
+  DoTexImage2D(
+      GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0, 0);
+  DoBindFramebuffer(
+      GL_READ_FRAMEBUFFER, client_framebuffer_id_, kServiceFramebufferId);
+  DoFramebufferTexture2D(
+      GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
+      kFBOClientTextureId, kFBOServiceTextureId, 0, GL_NO_ERROR);
+
+  SetupExpectationsForFramebufferClearingMulti(
+      kServiceFramebufferId,  // read framebuffer service id
+      0,                      // backbuffer service id
+      GL_READ_FRAMEBUFFER,    // target
+      GL_COLOR_BUFFER_BIT,    // clear bits
+      0, 0, 0, 0,             // color
+      0,                      // stencil
+      1.0f,                   // depth
+      false);                 // scissor test
+
+  EXPECT_CALL(*gl_, GetError())
+     .WillOnce(Return(GL_NO_ERROR))
+     .WillOnce(Return(GL_NO_ERROR))
+     .RetiresOnSaturation();
+  EXPECT_CALL(*gl_, ReadPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, _))
+      .Times(1)
+      .RetiresOnSaturation();
+  typedef ReadPixels::Result Result;
+  uint32 result_shm_id = kSharedMemoryId;
+  uint32 result_shm_offset = kSharedMemoryOffset;
+  uint32 pixels_shm_id = kSharedMemoryId;
+  uint32 pixels_shm_offset = kSharedMemoryOffset + sizeof(Result);
+  ReadPixels cmd;
+  cmd.Init(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE,
+         pixels_shm_id, pixels_shm_offset,
+         result_shm_id, result_shm_offset);
+  EXPECT_EQ(error::kNoError, ExecuteCmd(cmd));
+  EXPECT_EQ(GL_NO_ERROR, GetGLError());
+}
+
 TEST_F(GLES2DecoderWithShaderTest, DrawClearsAfterRenderbufferStorageInFBO) {
   SetupTexture();
   DoBindRenderbuffer(GL_RENDERBUFFER, client_renderbuffer_id_,
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
index 9010fb9..3a7c29d 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc
@@ -344,11 +344,46 @@ void GLES2DecoderTestBase::SetupExpectationsForFramebufferClearing(
     GLuint restore_stencil,
     GLclampf restore_depth,
     bool restore_scissor_test) {
+  SetupExpectationsForFramebufferClearingMulti(
+      0,
+      0,
+      target,
+      clear_bits,
+      restore_red,
+      restore_green,
+      restore_blue,
+      restore_alpha,
+      restore_stencil,
+      restore_depth,
+      restore_scissor_test);
+}
+
+void GLES2DecoderTestBase::SetupExpectationsForFramebufferClearingMulti(
+    GLuint read_framebuffer_service_id,
+    GLuint draw_framebuffer_service_id,
+    GLenum target,
+    GLuint clear_bits,
+    GLclampf restore_red,
+    GLclampf restore_green,
+    GLclampf restore_blue,
+    GLclampf restore_alpha,
+    GLuint restore_stencil,
+    GLclampf restore_depth,
+    bool restore_scissor_test) {
   // TODO(gman): Figure out why InSequence stopped working.
   // InSequence sequence;
   EXPECT_CALL(*gl_, CheckFramebufferStatusEXT(target))
       .WillOnce(Return(GL_FRAMEBUFFER_COMPLETE))
       .RetiresOnSaturation();
+  if (target == GL_READ_FRAMEBUFFER_EXT) {
+    EXPECT_CALL(*gl_, BindFramebufferEXT(GL_READ_FRAMEBUFFER_EXT, 0))
+        .Times(1)
+        .RetiresOnSaturation();
+    EXPECT_CALL(*gl_, BindFramebufferEXT(
+        GL_DRAW_FRAMEBUFFER_EXT, read_framebuffer_service_id))
+        .Times(1)
+        .RetiresOnSaturation();
+  }
   if ((clear_bits & GL_COLOR_BUFFER_BIT) != 0) {
     EXPECT_CALL(*gl_, ClearColor(0.0f, 0.0f, 0.0f, 0.0f))
         .Times(1)
@@ -394,6 +429,16 @@ void GLES2DecoderTestBase::SetupExpectationsForFramebufferClearing(
         .Times(1)
         .RetiresOnSaturation();
   }
+  if (target == GL_READ_FRAMEBUFFER_EXT) {
+    EXPECT_CALL(*gl_, BindFramebufferEXT(
+        GL_READ_FRAMEBUFFER_EXT, read_framebuffer_service_id))
+        .Times(1)
+        .RetiresOnSaturation();
+    EXPECT_CALL(*gl_, BindFramebufferEXT(
+        GL_DRAW_FRAMEBUFFER_EXT, draw_framebuffer_service_id))
+        .Times(1)
+        .RetiresOnSaturation();
+  }
 }
 
 void GLES2DecoderTestBase::SetupShaderForUniform() {
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.h b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.h
index f98aea4..92abfc0 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.h
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.h
@@ -326,26 +326,39 @@ class GLES2DecoderTestBase : public testing::Test {
       GLsizei height);
 
   void SetupExpectationsForFramebufferClearing(
-    GLenum target,
-    GLuint clear_bits,
-    GLclampf restore_red,
-    GLclampf restore_green,
-    GLclampf restore_blue,
-    GLclampf restore_alpha,
-    GLuint restore_stencil,
-    GLclampf restore_depth,
-    bool restore_scissor_test);
+      GLenum target,
+      GLuint clear_bits,
+      GLclampf restore_red,
+      GLclampf restore_green,
+      GLclampf restore_blue,
+      GLclampf restore_alpha,
+      GLuint restore_stencil,
+      GLclampf restore_depth,
+      bool restore_scissor_test);
+
+  void SetupExpectationsForFramebufferClearingMulti(
+      GLuint read_framebuffer_service_id,
+      GLuint draw_framebuffer_service_id,
+      GLenum target,
+      GLuint clear_bits,
+      GLclampf restore_red,
+      GLclampf restore_green,
+      GLclampf restore_blue,
+      GLclampf restore_alpha,
+      GLuint restore_stencil,
+      GLclampf restore_depth,
+      bool restore_scissor_test);
 
   void SetupExpectationsForApplyingDirtyState(
-    bool framebuffer_is_rgb,
-    bool framebuffer_has_depth,
-    bool framebuffer_has_stencil,
-    GLuint color_bits,  // NOTE! bits are 0x1000, 0x0100, 0x0010, and 0x0001
-    bool depth_mask,
-    bool depth_enabled,
-    GLuint front_stencil_mask,
-    GLuint back_stencil_mask,
-    bool stencil_enabled);
+      bool framebuffer_is_rgb,
+      bool framebuffer_has_depth,
+      bool framebuffer_has_stencil,
+      GLuint color_bits,  // NOTE! bits are 0x1000, 0x0100, 0x0010, and 0x0001
+      bool depth_mask,
+      bool depth_enabled,
+      GLuint front_stencil_mask,
+      GLuint back_stencil_mask,
+      bool stencil_enabled);
 
   void SetupExpectationsForApplyingDefaultDirtyState();