Add support to send optimal format as part of ScheduleOverlayPlane

gpu/command_buffer/service/gles2_cmd_decoder.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 "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 155 matching lines @@
       return gfx::OVERLAY_TRANSFORM_ROTATE_90;
     case GL_OVERLAY_TRANSFORM_ROTATE_180_CHROMIUM:
       return gfx::OVERLAY_TRANSFORM_ROTATE_180;
     case GL_OVERLAY_TRANSFORM_ROTATE_270_CHROMIUM:
       return gfx::OVERLAY_TRANSFORM_ROTATE_270;
     default:
       return gfx::OVERLAY_TRANSFORM_INVALID;
   }
 }
 
+gfx::BufferFormat GetGFXOverlayStorageFormat(GLuint storage_format) {
+  switch (storage_format) {
+    case GL_BGR:
+      return gfx::BufferFormat::BGRX_8888;
+    case GL_BGRA_EXT:
+      return gfx::BufferFormat::BGRA_8888;
+    case GL_RGB_YCBCR_422_CHROMIUM:
+      return gfx::BufferFormat::UYVY_422;
+    default:
+      NOTREACHED();
+      return gfx::BufferFormat::BGRX_8888;
+  }
+}
+
 template <typename MANAGER_TYPE, typename OBJECT_TYPE>
 GLuint GetClientId(const MANAGER_TYPE* manager, const OBJECT_TYPE* object) {
   DCHECK(manager);
   GLuint client_id = 0;
   if (object) {
     manager->GetClientId(object->service_id(), &client_id);
   }
   return client_id;
 }
 
@@ skipping 9240 matching lines @@
   gfx::OverlayTransform transform = GetGFXOverlayTransform(c.plane_transform);
   if (transform == gfx::OVERLAY_TRANSFORM_INVALID) {
     LOCAL_SET_GL_ERROR(GL_INVALID_ENUM,
                        "glScheduleOverlayPlaneCHROMIUM",
                        "invalid transform enum");
     return error::kNoError;
   }
   if (!surface_->ScheduleOverlayPlane(
           c.plane_z_order,
           transform,
+          GetGFXOverlayStorageFormat(c.storage_format),

[piman, 2015/12/11 08:32:25]

When would this be different than the image's BufferFormat?
What happens if they don't match? We can't trust the client.

[kalyank, 2015/12/11 19:22:35]

This might be different in case HardwarePlanes support formats
which can reduce the bandwidth. In ChromeOS case we hardcode these
checks in GbmPixmap 
https://code.google.com/p/chromium/codesearch#chromium/src/ui/ozone/platform/...

https://code.google.com/p/chromium/codesearch#chromium/src/ui/ozone/platform/...

We decide if we need to do any format conversions or handle any scaling requests
and do it here. This is wrong as some hardware might not support these
formats or can handle plane scaling (would help reduce bandwidth in upscaling
cases). This information needs to come from HardwareDisplayPlaneManager and will
vary depending on the combination of layers using HardwarePlanes during a page
flip request. The other option would be to query this from PlaneManager while
scheduling the plane, however this would mean having to maintain a cache of
Overlay configurations being in use and making sure it's in sync with the
pending swaps in GLSurfaceOzone.

https://code.google.com/p/chromium/codesearch#chromium/src/ui/ozone/platform/...

           image,
           gfx::Rect(c.bounds_x, c.bounds_y, c.bounds_width, c.bounds_height),
-          gfx::RectF(c.uv_x, c.uv_y, c.uv_width, c.uv_height))) {
+          gfx::RectF(c.uv_x, c.uv_y, c.uv_width, c.uv_height),
+          static_cast<GLboolean>(c.handle_scaling))) {

[piman, 2015/12/11 08:32:25]

Same here, what happens if handle_scaling doesn't match whether
(uv_width,uv_height)*image->GetSize() is equal to (bounds_width,bounds_height)?

     LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION,
                        "glScheduleOverlayPlaneCHROMIUM",
                        "failed to schedule overlay");
   }
   return error::kNoError;
 }
 
 error::Error GLES2DecoderImpl::HandleScheduleCALayerCHROMIUM(
     uint32 immediate_data_size,
     const void* cmd_data) {
@@ skipping 6179 matching lines @@
   return error::kNoError;
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu