ReleaseOutputBuffer to surface back and front buffers where possible.

content/common/gpu/media/avda_codec_image.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_AVDA_CODEC_IMAGE_H_
 #define CONTENT_COMMON_GPU_MEDIA_AVDA_CODEC_IMAGE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 34 matching lines @@
                             const gfx::RectF& crop_rect) override;
   void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                     uint64_t process_tracing_id,
                     const std::string& dump_name) override;
   // gpu::gles2::GLStreamTextureMatrix implementation
   void GetTextureMatrix(float xform[16]) override;
 
   // Decoded buffer index that has the image for us to display.
   void SetMediaCodecBufferIndex(int buffer_index);
 
-  // Return the codec buffer that we will return to the codec, or
-  // <0 if there is no such buffer.
-  int GetMediaCodecBufferIndex() const;
-
   // Set the size of the current image.
   void SetSize(const gfx::Size& size);
 
+  enum class ReleaseMode { SKIP_RENDER, RENDER_ONLY, RENDER_AND_UPDATE };

[liberato (no reviews please), 2016/04/22 00:51:06]

i think these might be better named { DISCARD_CODEC_BUFFER,
RENDER_TO_BACK_BUFFER, RENDER_TO_FRONT_BUFFER}

RENDER_AND_UPDATE is used for the surfaceview case, but there's no notion of
updating.

[DaleCurtis, 2016/04/22 01:33:58]

I like it. Done.

+  void ReleaseOutputBuffer(ReleaseMode release_mode);
+
+  // Indicates if the codec buffer has been released to the back buffer.
+  bool is_rendered_to_back_buffer() const {
+    return codec_buffer_index_ == kUpdateOnly;
+  }
+
+  // Indicates if the codec buffer has been released to the front or back
+  // buffer.
+  bool is_rendered() const {
+    return codec_buffer_index_ <= kInvalidCodecBufferIndex;
+  }
+
   // Updates the MediaCodec for this image; clears |codec_buffer_index_|.
   void SetMediaCodec(media::MediaCodecBridge* codec);
 
   void SetTexture(gpu::gles2::Texture* texture);
 
  protected:
   ~AVDACodecImage() override;
 
+  enum { kInvalidCodecBufferIndex = -1, kUpdateOnly = -2 };
+
  private:
-  enum { kInvalidCodecBufferIndex = -1 };
-
   // Make sure that the surface texture's front buffer is current.  This will
   // save / restore the current context.  It will optionally restore the texture
   // bindings in the surface texture's context, based on |mode|.  This is
   // intended as a hint if we don't need to change contexts.  If we do need to
   // change contexts, then we'll always preserve the texture bindings in the
   // both contexts.  In other words, the caller is telling us whether it's
   // okay to change the binding in the current context.
   enum RestoreBindingsMode { kDontRestoreBindings, kDoRestoreBindings };
   void UpdateSurfaceTexture(RestoreBindingsMode mode);
 
@@ skipping 41 matching lines @@
 
   // Texture matrix of the front buffer of the surface texture.
   float gl_matrix_[16];
 
   DISALLOW_COPY_AND_ASSIGN(AVDACodecImage);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_AVDA_CODEC_IMAGE_H_