rendering_helper - Wait for rendering before resetting the decoder.

content/common/gpu/media/rendering_helper.cc

 // Copyright 2013 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.
 
 #include "content/common/gpu/media/rendering_helper.h"
 
 #include <algorithm>
 #include <numeric>
 #include <vector>
 
@@ skipping 76 matching lines @@
   return gfx::GLSurface::InitializeOneOff();
 }
 
 RenderingHelper::RenderingHelper() {
   window_ = gfx::kNullAcceleratedWidget;
   Clear();
 }
 
 RenderingHelper::~RenderingHelper() {
   CHECK_EQ(clients_.size(), 0U) << "Must call UnInitialize before dtor.";
   Clear();

[Pawel Osciak, 2014/08/14 05:11:07]

Should we assert that pending frames are empty?

[Owen Lin, 2014/08/14 10:55:35]

It's OK to have pending frames, Clear() will also clear it.

 }
 
 void RenderingHelper::Initialize(const RenderingHelperParams& params,
                                  base::WaitableEvent* done) {
   // Use clients_.size() != 0 as a proxy for the class having already been
   // Initialize()'d, and UnInitialize() before continuing.
   if (clients_.size()) {
     base::WaitableEvent done(false, false);
     UnInitialize(&done);
     done.Wait();
@@ skipping 375 matching lines @@
     *rgb_ptr++ = *rgba_ptr++;
     *rgb_ptr++ = *rgba_ptr++;
     solid = solid && (*rgba_ptr == 0xff);
     rgba_ptr++;
   }
   *alpha_solid = solid;
 
   done->Signal();
 }
 
+void RenderingHelper::SetWaitRenderingCB(
+    size_t window_id,
+    const base::Closure& wait_rendering_cb) {
+  RenderingClient* client = &clients_[window_id];
+  if (client->pending_frames.empty() || client->last_frame_rendered) {
+    // The rendering has been completed.
+    wait_rendering_cb.Run();
+    return;
+  }
+  client->wait_rendering_cb = wait_rendering_cb;
+}
+
 void RenderingHelper::RenderContent() {
   CHECK_EQ(base::MessageLoop::current(), message_loop_);
   glUniform1i(glGetUniformLocation(program_, "tex_flip"), 1);
 
   if (render_as_thumbnails_) {
     // In render_as_thumbnails_ mode, we render the FBO content on the
     // screen instead of the decoded textures.
     GLSetViewPort(clients_[0].render_area);
     RenderTexture(GL_TEXTURE_2D, thumbnails_texture_id_);
     gl_surface_->SwapBuffers();
@@ skipping 14 matching lines @@
   // Releases the rendered frame after SwapBuffers() if it is not the last one.
   for (size_t i = 0; i < clients_.size(); ++i) {
     RenderingClient* client = &clients_[i];
     if (client->pending_frames.size() > 1) {
       delete client->pending_frames.front();
       client->pending_frames.pop_front();
       client->last_frame_rendered = false;
       continue;
     }
     client->last_frame_rendered = true;
+    if (!client->wait_rendering_cb.is_null())
+      base::ResetAndReturn(&client->wait_rendering_cb).Run();

[Pawel Osciak, 2014/08/14 05:11:07]

I think we have to pop the last frame here?

[Owen Lin, 2014/08/14 10:55:35]

Done.

   }
 }
 
 // Helper function for the LayoutRenderingAreas(). The |lengths| are the
 // heights(widths) of the rows(columns). It scales the elements in
 // |lengths| proportionally so that the sum of them equal to |total_length|.
 // It also outputs the coordinates of the rows(columns) to |offsets|.
 static void ScaleAndCalculateOffsets(std::vector<int>* lengths,
                                      std::vector<int>* offsets,
                                      int total_length) {
@@ skipping 37 matching lines @@
     scale = std::min(1.0f, scale);
 
     size_t w = scale * size.width();
     size_t h = scale * size.height();
     size_t x = offset_x[i % cols] + (widths[i % cols] - w) / 2;
     size_t y = offset_y[i / cols] + (heights[i / cols] - h) / 2;
     clients_[i].render_area = gfx::Rect(x, y, w, h);
   }
 }
 }  // namespace content