Implement on demand quad rasterization for PicturePiles.

cc/resources/resource_provider.cc

 // Copyright 2012 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 "cc/resources/resource_provider.h"
 
 #include <limits.h>
 
 #include "base/debug/alias.h"
 #include "base/hash_tables.h"
@@ skipping 251 matching lines @@
   ResourceId id = next_id_++;
   unsigned texture_id = 0;
   Resource resource(texture_id, gfx::Size(), 0, GL_LINEAR);
   resource.external = true;
   resource.allocated = true;
   resource.mailbox = mailbox;
   resources_[id] = resource;
   return id;
 }
 
+void ResourceProvider::ResizeResource(ResourceId id, gfx::Size size) {

[reveman, 2013/03/22 23:56:50]

I don't understand why we need this function.

[Leandro Graciá Gil, 2013/03/25 15:21:02]

Considering all the details that need to be tracked and the problems this might
introduce, I'm reviewing the assumptions that led to introducing this function.
I'll make an overall comment in the next iteration of the patch.

+  DCHECK(thread_checker_.CalledOnValidThread());
+  ResourceMap::iterator it = resources_.find(id);
+  CHECK(it != resources_.end());
+  Resource* resource = &it->second;
+  DCHECK(!resource->lock_for_read_count);
+  DCHECK(!resource->marked_for_deletion);
+  DCHECK(resource->pending_set_pixels || !resource->locked_for_write);
+  DCHECK(!resource->exported);
+  DCHECK(!resource->external);
+  DCHECK(!resource->gl_pixel_buffer_id && !resource->pixel_buffer);
+
+  if (resource->size != size) {
+    switch (resource->type) {
+    case GLTexture:
+      DCHECK_LE(size.width(), max_texture_size_);
+      DCHECK_LE(size.height(), max_texture_size_);
+      resource->allocated = false;
+      break;
+

[piman, 2013/03/22 20:52:34]

nit: no need for blank line.

+    case Bitmap:
+      DCHECK(resource->pixels);
+      delete[] resource->pixels;
+      resource->pixels = new uint8_t[size.width() * size.height() * 4];
+      resource->allocated = true;
+      break;
+
+    default:
+      NOTREACHED();

[piman, 2013/03/22 20:52:34]

nit: we usually don't add the default clause when switching on an enum, so that
we get a compiler warning if adding an enum value.

+    }
+
+    resource->size = size;
+  }
+}
+
 void ResourceProvider::DeleteResource(ResourceId id) {
   DCHECK(thread_checker_.CalledOnValidThread());
   ResourceMap::iterator it = resources_.find(id);
   CHECK(it != resources_.end());
   Resource* resource = &it->second;
   DCHECK(!resource->lock_for_read_count);
   DCHECK(!resource->marked_for_deletion);
   DCHECK(resource->pending_set_pixels || !resource->locked_for_write);
 
   if (resource->exported) {
@@ skipping 920 matching lines @@
 void ResourceProvider::EnableReadLockFences(ResourceProvider::ResourceId id,
                                             bool enable) {
   DCHECK(thread_checker_.CalledOnValidThread());
   ResourceMap::iterator it = resources_.find(id);
   CHECK(it != resources_.end());
   Resource* resource = &it->second;
   resource->enable_read_lock_fences = enable;
 }
 
 }  // namespace cc