Implement video renderer based on VideoDecode API.

remoting/client/plugin/pepper_video_renderer_3d.h

+// Copyright 2014 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 REMOTING_CLIENT_PLUGIN_PEPPER_VIDEO_RENDERER_3D_H_
+#define REMOTING_CLIENT_PLUGIN_PEPPER_VIDEO_RENDERER_3D_H_
+
+#include <deque>
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "ppapi/cpp/graphics_3d.h"
+#include "ppapi/cpp/instance_handle.h"
+#include "ppapi/cpp/video_decoder.h"
+#include "ppapi/utility/completion_callback_factory.h"
+#include "remoting/client/chromoting_stats.h"
+#include "remoting/client/plugin/pepper_video_renderer.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_geometry.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_region.h"
+
+struct PPB_OpenGLES2;
+
+namespace remoting {
+
+// PepperVideoRenderer that uses the PPB_VideoDecoder interface for video
+// decoding and Graphics3D for rendering.
+class PepperVideoRenderer3D : public PepperVideoRenderer {
+ public:
+  PepperVideoRenderer3D();
+  ~PepperVideoRenderer3D() override;
+
+  // PepperVideoRenderer interface.
+  bool Initialize(pp::Instance* instance,
+                  const ClientContext& context,
+                  EventHandler* event_handler) override;
+  void OnViewChanged(const pp::View& view) override;
+  void OnSessionConfig(const protocol::SessionConfig& config) override;
+  ChromotingStats* GetStats() override;
+  void ProcessVideoPacket(scoped_ptr<VideoPacket> packet,
+                          const base::Closure& done) override;
+
+ private:
+  class PendingPacket;
+  class Picture;
+
+  struct FrameDecodeTimestamp {
+    FrameDecodeTimestamp(uint32_t frame_id,
+                         base::TimeTicks decode_started_time);
+    uint32_t frame_id;
+    base::TimeTicks decode_started_time;
+  };
+
+  // Callback for pp::VideoDecoder::Initialize().
+  void OnInitialized(int32_t result);
+
+  // Passes one picture from |pending_packets_| to the |video_decoder_|.
+  void DecodeNextPacket();
+
+  // Callback for pp::VideoDecoder::Decode().
+  void OnDecodeDone(int32_t result);
+
+  // Fetches next picture from the |video_decoder_|.
+  void GetNextPicture();
+
+  // Callback for pp::VideoDecoder::GetPicture().
+  void OnPictureReady(int32_t result, PP_VideoPicture picture);
+
+  // Copies |next_picture_| to |current_picture_| if |next_picture_| is set and
+  // then renders |current_picture_|. Doesn't do anything if |need_repaint_| is
+  // false.
+  void Paint();

[Wez, 2015/01/06 22:17:10]

Suggest renaming to PaintIfNeeded().

[Sergey Ulanov, 2015/01/07 19:37:31]

Done.

+
+  // Callback for pp::Graphics3D::SwapBuffers().
+  void OnPaintDone(int32_t result);
+
+  // Initializes |shader_program_| for |texture_target|.
+  void EnsureProgramForTexture(uint32_t texture_target);
+
+  // Initializes |shader_program_| with the given shaders.
+  void CreateProgram(const char* vertex_shader, const char* fragment_shader);
+
+  // Creates a new shader and compiles |source| for it.
+  void CreateShaderProgram(int type, const char* source);
+
+  // CHECKs that the last OpenGL call has completed successfully.
+  void CheckGLError();
+
+  EventHandler* event_handler_;
+
+  pp::Graphics3D graphics_;
+  const PPB_OpenGLES2* gles2_if_;
+  pp::VideoDecoder video_decoder_;
+
+  webrtc::DesktopSize frame_size_;
+  webrtc::DesktopVector frame_dpi_;
+  webrtc::DesktopRegion desktop_shape_;
+
+  webrtc::DesktopSize view_size_;
+
+  ChromotingStats stats_;
+  int64 last_input_event_timestamp_ ;
+
+  bool initialization_finished_;
+  bool decode_pending_;
+  bool get_picture_pending_;
+  bool paint_pending_;
+
+  uint32_t last_frame_id_;
+
+  // Queue of packets that that have been received, but haven't been passed to
+  // the decoder yet.
+  std::deque<PendingPacket*> pending_packets_;
+
+  // Timestamps for all frames currently being processed by the decoder.
+  std::deque<FrameDecodeTimestamp> frame_decode_timestamps_;
+
+  // The current picture shown on the screen or being rendered.
+  scoped_ptr<Picture> current_picture_;
+
+  // The next picture to be rendered. Paint() will copy it to |current_picture_|
+  // and render it after that.
+  scoped_ptr<Picture> next_picture_;

[Wez, 2015/01/06 22:17:10]

nit: Might be worth noting that this and current_picture_ must be deleted
_before_ video_decoder_.

[Sergey Ulanov, 2015/01/07 19:37:30]

Done.

+
+  // Set to true if the screen needs to be repainted because a new frame was
+  // received of the plugin was resized.

[Wez, 2015/01/06 22:17:10]

s/of/or

[Sergey Ulanov, 2015/01/07 19:37:31]

Done.

+  bool need_repaint_;
+
+  // Time the last paint operation was started.
+  base::TimeTicks last_paint_started_time_;
+
+  // The texture type for which |shader_program| was initialized. Can be either
+  // 0, GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE_ARB or GL_TEXTURE_EXTERNAL_OES.

[Wez, 2015/01/06 22:17:10]

What does a value of 0 mean, though?

[Sergey Ulanov, 2015/01/07 19:37:31]

Done.

+  uint32_t current_shader_program_texture_target_;
+
+  // Shader program ID.
+  unsigned int shader_program_;
+
+  // Location of the scale value to be passed to the |shader_program_|.
+  int shader_texcoord_scale_location_;
+
+  pp::CompletionCallbackFactory<PepperVideoRenderer3D> callback_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperVideoRenderer3D);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_CLIENT_PLUGIN_PEPPER_VIDEO_RENDERER_3D_H_