Fix use_image_texture_target inconsistencies

ui/compositor/compositor.cc

 // Copyright (c) 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 "ui/compositor/compositor.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <deque>
@@ skipping 19 matching lines @@
 #include "cc/scheduler/begin_frame_source.h"
 #include "cc/surfaces/surface_id_allocator.h"
 #include "cc/trees/layer_tree_host.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/compositor_switches.h"
 #include "ui/compositor/compositor_vsync_manager.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animator_collection.h"
-#include "ui/gl/gl_context.h"
 #include "ui/gl/gl_switches.h"
 
 namespace {
 
 const double kDefaultRefreshRate = 60.0;
 const double kTestRefreshRate = 200.0;
 
 bool IsRunningInMojoShell(base::CommandLine* command_line) {
   const char kMojoShellFlag[] = "mojo-platform-channel-handle";
   return command_line->HasSwitch(kMojoShellFlag);
@@ skipping 101 matching lines @@
   if (command_line->HasSwitch(switches::kUIEnableRGBA4444Textures))
     settings.renderer_settings.preferred_tile_format = cc::RGBA_4444;
 
   settings.use_layer_lists =
       command_line->HasSwitch(cc::switches::kUIEnableLayerLists);
 
   // UI compositor always uses partial raster if not using zero-copy. Zero copy
   // doesn't currently support partial raster.
   settings.use_partial_raster = !settings.use_zero_copy;
 
-  // Use CPU_READ_WRITE_PERSISTENT memory buffers to support partial tile
-  // raster if needed.
-  gfx::BufferUsage usage =
-      settings.use_partial_raster
-          ? gfx::BufferUsage::GPU_READ_CPU_READ_WRITE_PERSISTENT
-          : gfx::BufferUsage::GPU_READ_CPU_READ_WRITE;
-
-  for (size_t format = 0;
-      format < static_cast<size_t>(gfx::BufferFormat::LAST) + 1; format++) {
-    DCHECK_GT(settings.use_image_texture_targets.size(), format);
-    settings.use_image_texture_targets[format] =
-        context_factory_->GetImageTextureTarget(
-            static_cast<gfx::BufferFormat>(format), usage);
+  // Populate buffer_to_texture_target_map for all buffer usage/formats.
+  for (size_t usage_idx = 0;

[danakj, 2016/07/19 20:37:56]

why size_t and not int?

[ericrk, 2016/07/19 21:47:46]

No reason - previous code used size_t, but I can't see a strong reason why -
changing to int.

+       usage_idx < static_cast<size_t>(gfx::BufferUsage::LAST) + 1;

[danakj, 2016/07/19 20:37:56]

nit: use <= instead of +1

[ericrk, 2016/07/19 21:47:46]

Done.

+       ++usage_idx) {
+    gfx::BufferUsage usage = static_cast<gfx::BufferUsage>(usage_idx);
+    for (size_t format_idx = 0;

[danakj, 2016/07/19 20:37:56]

why size_t and not int?

[ericrk, 2016/07/19 21:47:46]

Done.

+         format_idx < static_cast<size_t>(gfx::BufferFormat::LAST) + 1;

[danakj, 2016/07/19 20:37:56]

nit: <= instead of +1

[ericrk, 2016/07/19 21:47:46]

Done.

+         ++format_idx) {
+      gfx::BufferFormat format = static_cast<gfx::BufferFormat>(format_idx);
+      uint32_t target = context_factory_->GetImageTextureTarget(format, usage);
+      settings.renderer_settings.buffer_to_texture_target_map.emplace(
+          cc::BufferToTextureTargetKey(usage, format), target);
+    }
   }
 
   // Note: Only enable image decode tasks if we have more than one worker
   // thread.
   settings.image_decode_tasks_enabled = false;
 
   // TODO(crbug.com/603600): This should always be turned on once mus tells its
   // clients about BeginFrame.
   settings.use_output_surface_begin_frame_source =
       !IsRunningInMojoShell(command_line);
@@ skipping 315 matching lines @@
                     observer_list_,
                     OnCompositingLockStateChanged(this));
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
 }  // namespace ui