Don't call into driver for unsupported extensions.

Check extension availability for glDiscardFramebufferEXT()
and glBlitFramebufferEXT().

Adds some tests for glDiscardFramebuffer() also.

Review URL: https://codereview.chromium.org/46673007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232165 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 77 insertions, 1 deletions

diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 6e6b363..9329bc5 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -122,7 +122,8 @@ FeatureInfo::FeatureFlags::FeatureFlags()
       ext_draw_buffers(false),
       ext_frag_depth(false),
       use_async_readpixels(false),
-      map_buffer_range(false) {
+      map_buffer_range(false),
+      ext_discard_framebuffer(false) {
 }
 
 FeatureInfo::Workarounds::Workarounds() :
@@ -697,6 +698,7 @@ void FeatureInfo::InitializeFeatures() {
       !workarounds_.disable_ext_discard_framebuffer) {
     // DiscardFramebufferEXT is automatically bound to InvalidateFramebuffer.
     AddExtensionString("GL_EXT_discard_framebuffer");
+    feature_flags_.ext_discard_framebuffer = true;
   }
 }
 
diff --git a/gpu/command_buffer/service/feature_info.h b/gpu/command_buffer/service/feature_info.h
index 7d5041f..1b0fc77 100644
--- a/gpu/command_buffer/service/feature_info.h
+++ b/gpu/command_buffer/service/feature_info.h
@@ -51,6 +51,7 @@ class GPU_EXPORT FeatureInfo : public base::RefCounted<FeatureInfo> {
     bool ext_frag_depth;
     bool use_async_readpixels;
     bool map_buffer_range;
+    bool ext_discard_framebuffer;
   };
 
   struct Workarounds {
diff --git a/gpu/command_buffer/service/feature_info_unittest.cc b/gpu/command_buffer/service/feature_info_unittest.cc
index c5e8301..5b07106 100644
--- a/gpu/command_buffer/service/feature_info_unittest.cc
+++ b/gpu/command_buffer/service/feature_info_unittest.cc
@@ -116,6 +116,7 @@ TEST_F(FeatureInfoTest, Basic) {
   EXPECT_FALSE(info_->feature_flags().native_vertex_array_object);
   EXPECT_FALSE(info_->feature_flags().map_buffer_range);
   EXPECT_FALSE(info_->feature_flags().use_async_readpixels);
+  EXPECT_FALSE(info_->feature_flags().ext_discard_framebuffer);
 
 #define GPU_OP(type, name) EXPECT_FALSE(info_->workarounds().name);
   GPU_DRIVER_BUG_WORKAROUNDS(GPU_OP)
@@ -850,6 +851,12 @@ TEST_F(FeatureInfoTest, InitializeEXT_frag_depth) {
   EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_frag_depth"));
 }
 
+TEST_F(FeatureInfoTest, InitializeEXT_discard_framebuffer) {
+  SetupInitExpectations("GL_EXT_discard_framebuffer");
+  EXPECT_TRUE(info_->feature_flags().ext_discard_framebuffer);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_discard_framebuffer"));
+}
+
 TEST_F(FeatureInfoTest, InitializeSamplersWithARBSamplerObjects) {
   SetupInitExpectationsWithGLVersion("GL_ARB_sampler_objects", "OpenGL 3.0");
   EXPECT_TRUE(info_->feature_flags().enable_samplers);
@@ -859,6 +866,8 @@ TEST_F(FeatureInfoTest, InitializeWithES3) {
   SetupInitExpectationsWithGLVersion("", "OpenGL ES 3.0");
   EXPECT_TRUE(info_->feature_flags().enable_samplers);
   EXPECT_TRUE(info_->feature_flags().map_buffer_range);
+  EXPECT_TRUE(info_->feature_flags().ext_discard_framebuffer);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_discard_framebuffer"));
   EXPECT_FALSE(info_->feature_flags().use_async_readpixels);
 }
 
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 2e82d98..be0ee10 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -3892,6 +3892,13 @@ void GLES2DecoderImpl::DoDisableVertexAttribArray(GLuint index) {
 void GLES2DecoderImpl::DoDiscardFramebufferEXT(GLenum target,
                                                GLsizei numAttachments,
                                                const GLenum* attachments) {
+  if (!features().ext_discard_framebuffer) {
+    LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION,
+                       "glDiscardFramebufferEXT",
+                       "function not available");
+    return;
+  }
+
   Framebuffer* framebuffer =
       GetFramebufferInfoForTarget(GL_FRAMEBUFFER);
 
@@ -4977,6 +4984,7 @@ void GLES2DecoderImpl::DoBlitFramebufferEXT(
     LOCAL_SET_GL_ERROR(
         GL_INVALID_OPERATION,
         "glBlitFramebufferEXT", "function not available");
+    return;
   }
 
   if (!CheckBoundFramebuffersValid("glBlitFramebufferEXT")) {
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
index 573ba6e..af127bf 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder_unittest.cc
@@ -8610,6 +8610,62 @@ TEST_F(GLES2DecoderTest, DrawBuffersEXTImmediateBackbuffer) {
   EXPECT_EQ(GL_NO_ERROR, GetGLError());
 }
 
+TEST_F(GLES2DecoderManualInitTest, DiscardFramebufferEXT) {
+  InitDecoder("GL_EXT_discard_framebuffer",  // extensions
+              false,                         // has alpha
+              false,                         // has depth
+              false,                         // has stencil
+              false,                         // request alpha
+              false,                         // request depth
+              false,                         // request stencil
+              false);                        // bind generates resource
+
+  const GLenum target = GL_FRAMEBUFFER;
+  const GLsizei count = 1;
+  const GLenum attachments[] = { GL_COLOR_ATTACHMENT0 };
+
+  SetupTexture();
+  DoBindFramebuffer(
+      GL_FRAMEBUFFER, client_framebuffer_id_, kServiceFramebufferId);
+  DoFramebufferTexture2D(GL_FRAMEBUFFER,
+                         GL_COLOR_ATTACHMENT0,
+                         GL_TEXTURE_2D,
+                         client_texture_id_,
+                         kServiceTextureId,
+                         0,
+                         GL_NO_ERROR);
+  FramebufferManager* framebuffer_manager = group().framebuffer_manager();
+  Framebuffer* framebuffer =
+      framebuffer_manager->GetFramebuffer(client_framebuffer_id_);
+  EXPECT_TRUE(framebuffer->IsCleared());
+
+  EXPECT_CALL(*gl_, DiscardFramebufferEXT(target, count, _))
+      .Times(1)
+      .RetiresOnSaturation();
+  DiscardFramebufferEXTImmediate& cmd =
+      *GetImmediateAs<DiscardFramebufferEXTImmediate>();
+  cmd.Init(target, count, attachments);
+
+  EXPECT_EQ(error::kNoError,
+            ExecuteImmediateCmd(cmd, sizeof(attachments)));
+  EXPECT_EQ(GL_NO_ERROR, GetGLError());
+  EXPECT_FALSE(framebuffer->IsCleared());
+}
+
+TEST_F(GLES2DecoderTest, DiscardFramebufferEXTUnsupported) {
+  const GLenum target = GL_FRAMEBUFFER;
+  const GLsizei count = 1;
+  const GLenum attachments[] = { GL_COLOR_EXT };
+  DiscardFramebufferEXTImmediate& cmd =
+      *GetImmediateAs<DiscardFramebufferEXTImmediate>();
+  cmd.Init(target, count, attachments);
+
+  // Should not result into a call into GL.
+  EXPECT_EQ(error::kNoError,
+            ExecuteImmediateCmd(cmd, sizeof(attachments)));
+  EXPECT_EQ(GL_INVALID_OPERATION, GetGLError());
+}
+
 // TODO(gman): Complete this test.
 // TEST_F(GLES2DecoderTest, CompressedTexImage2DGLError) {
 // }