Reset TexImage2D base level to workaround Intel mac driver bug

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 48593f2337e6b8873ee6c757e6f20b2276e23221..d85b8c8832e54f1066c58f0ae580ca536bd69448 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -322,6 +322,29 @@ class ScopedResolvedFramebufferBinder {
   DISALLOW_COPY_AND_ASSIGN(ScopedResolvedFramebufferBinder);
 };
 
+// Reset a texture's base level and restore it after calling texImage2D

[Ken Russell (switch to Gerrit), 2017/04/28 19:04:25]

Please revise: "Reset the base level of the texture currently bound to the
GL_TEXTURE_2D target and restore it after calling texImage2D."

But also see the comment below about the texture target. If this is generalized,
then revise this comment to match.

[yizhou.jiang, 2017/06/09 07:58:15]

Done.

+class ScopedTextureBaseLevelResetter {
+ public:
+  explicit ScopedTextureBaseLevelResetter(GLint base_level,
+                                          bool reset_base_level)

[Ken Russell (switch to Gerrit), 2017/04/28 19:04:25]

Please change the constructor to take in the target as an argument and
DCHECK(target == GL_TEXTURE_2D) inside this. Otherwise it will be too easy for
this class to be misused and do the wrong thing.

Or: if this workaround may be needed for other texture targets like
GL_TEXTURE_RECTANGLE_ARB too, just have this class apply the workaround to the
target.

[yizhou.jiang, 2017/06/09 07:58:15]

Done.

+      : base_level_(base_level), reset_base_level_(reset_base_level) {
+    if (reset_base_level_) {
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
+    }
+  }
+
+  ~ScopedTextureBaseLevelResetter() {
+    if (reset_base_level_) {
+      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, base_level_);
+    }
+  }
+
+ private:
+  GLint base_level_;
+  bool reset_base_level_;
+  DISALLOW_COPY_AND_ASSIGN(ScopedTextureBaseLevelResetter);
+};
+
 // Encapsulates an OpenGL texture.
 class BackTexture {
  public:
@@ -667,6 +690,7 @@ class GLES2DecoderImpl : public GLES2Decoder, public ErrorStateClient {
  private:
   friend class ScopedFramebufferBinder;
   friend class ScopedResolvedFramebufferBinder;
+  friend class ScopedTextureBaseLevelResetter;
   friend class BackFramebuffer;
   friend class BackRenderbuffer;
   friend class BackTexture;
@@ -6289,6 +6313,8 @@ void GLES2DecoderImpl::DoGenerateMipmap(GLenum target) {
     if (base_level != 0 &&
         !tex->GetLevelType(target, 0, &type, &internal_format) &&
         tex->GetLevelType(target, tex->base_level(), &type, &internal_format)) {
+      ScopedTextureBaseLevelResetter baseLevelResetter(
+          base_level, workarounds().reset_teximage2d_base_level);
       format = TextureManager::ExtractFormatFromStorageFormat(internal_format);
       glTexImage2D(target, 0, internal_format, 1, 1, 0, format, type, nullptr);

[Ken Russell (switch to Gerrit), 2017/04/28 19:04:25]

Can you think of any way to add a TexImage2DHelper to the command buffer, put
the use of the ScopedTextureBaseLevelResetter inside it, and change the
glTexImage2D calls here and throughout to call it?

The fact that glTexImage2D calls need to be paired with
ScopedTextureBaseLevelResetter is error-prone and will lead to bugs in the
future as other people edit this file and add more calls to glTexImage2D.

[yizhou.jiang, 2017/06/09 07:58:15]

Done.

       texture_zero_level_set = true;
@@ -6324,6 +6350,8 @@ void GLES2DecoderImpl::DoGenerateMipmap(GLenum target) {
     // This may have some unwanted side effects, but we expect command buffer
     // validation to prevent you from doing anything weird with the texture
     // after this, like calling texSubImage2D sucessfully.
+    ScopedTextureBaseLevelResetter baseLevelResetter(
+        base_level, workarounds().reset_teximage2d_base_level);
     glTexImage2D(target, 0, internal_format, 0, 0, 0, format, type, nullptr);
   }
 
@@ -13761,6 +13789,8 @@ error::Error GLES2DecoderImpl::DoCompressedTexImage(
     }
     state_.PushTextureDecompressionUnpackState();
     if (dimension == ContextState::k2D) {
+      ScopedTextureBaseLevelResetter baseLevelResetter(
+          texture->base_level(), workarounds().reset_teximage2d_base_level);
       glTexImage2D(target, level, format_info->decompressed_internal_format,
                    width, height, border, format_info->decompressed_format,
                    format_info->decompressed_type, decompressed_data.get());
@@ -14402,6 +14432,9 @@ void GLES2DecoderImpl::DoCopyTexImage2D(
 
       std::unique_ptr<char[]> zero(new char[pixels_size]);
       memset(zero.get(), 0, pixels_size);
+
+      ScopedTextureBaseLevelResetter baseLevelResetter(
+          texture->base_level(), workarounds().reset_teximage2d_base_level);
       glTexImage2D(target, level, final_internal_format, width, height, border,
                    format, type, zero.get());
     }
@@ -16878,6 +16911,8 @@ void GLES2DecoderImpl::DoCopyTextureCHROMIUM(
     // Ensure that the glTexImage2D succeeds.
     LOCAL_COPY_REAL_GL_ERRORS_TO_WRAPPER(kFunctionName);
     glBindTexture(dest_binding_target, dest_texture->service_id());
+    ScopedTextureBaseLevelResetter baseLevelResetter(
+        dest_texture->base_level(), workarounds().reset_teximage2d_base_level);
     glTexImage2D(dest_target, dest_level,
                  TextureManager::AdjustTexInternalFormat(feature_info_.get(),
                                                          internal_format),
@@ -17325,8 +17360,12 @@ void GLES2DecoderImpl::DoCompressedCopyTextureCHROMIUM(GLuint source_id,
 
   // As a fallback, copy into a non-compressed GL_RGBA texture.
   LOCAL_COPY_REAL_GL_ERRORS_TO_WRAPPER(kFunctionName);
-  glTexImage2D(dest_texture->target(), 0, GL_RGBA, source_width, source_height,
-               0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+  {
+    ScopedTextureBaseLevelResetter baseLevelResetter(
+        dest_texture->base_level(), workarounds().reset_teximage2d_base_level);
+    glTexImage2D(dest_texture->target(), 0, GL_RGBA, source_width,
+                 source_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+  }
   GLenum error = LOCAL_PEEK_GL_ERROR(kFunctionName);
   if (error != GL_NO_ERROR) {
     RestoreCurrentTextureBindings(&state_, dest_texture->target());