Add support for GL_CHROMIUM_pixel_transfer_buffer_object.

gpu/command_buffer/client/gles2_implementation.cc

Index: gpu/command_buffer/client/gles2_implementation.cc
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index e5e03ad616de3af16ecfaba5f899227d379996e1..9bc057e77835700c0a0b2fab4939019b218b9775 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -398,6 +398,8 @@ GLES2Implementation::GLES2Implementation(
       bound_renderbuffer_(0),
       bound_array_buffer_id_(0),
       bound_element_array_buffer_id_(0),
+      bound_pixel_pack_transfer_buffer_id_(0),
+      bound_pixel_unpack_transfer_buffer_id_(0),
       client_side_array_id_(0),
       client_side_element_array_id_(0),
       error_bits_(0),
@@ -468,6 +470,7 @@ bool GLES2Implementation::Initialize(
       new TextureUnit[gl_state_.int_state.max_combined_texture_image_units]);
 
   query_tracker_.reset(new QueryTracker(mapped_memory_.get()));
+  buffer_tracker_.reset(new BufferTracker(mapped_memory_.get()));
 
 #if defined(GLES2_SUPPORT_CLIENT_SIDE_ARRAYS)
   GetIdHandler(id_namespaces::kBuffers)->MakeIds(
@@ -489,6 +492,7 @@ GLES2Implementation::~GLES2Implementation() {
   // shared will fail and abort (ie, it will stop running).
   Finish();
   query_tracker_.reset();
+  buffer_tracker_.reset();
 
 #if defined(GLES2_SUPPORT_CLIENT_SIDE_ARRAYS)
   DeleteBuffers(arraysize(reserved_ids_), &reserved_ids_[0]);
@@ -885,6 +889,18 @@ bool GLES2Implementation::GetHelper(GLenum pname, GLint* params) {
         return true;
       }
       return false;
+    case GL_PIXEL_PACK_TRANSFER_BUFFER_BINDING_CHROMIUM:
+      if (share_group_->bind_generates_resource()) {
+        *params = bound_pixel_pack_transfer_buffer_id_;
+        return true;
+      }
+      return false;
+    case GL_PIXEL_UNPACK_TRANSFER_BUFFER_BINDING_CHROMIUM:
+      if (share_group_->bind_generates_resource()) {
+        *params = bound_pixel_unpack_transfer_buffer_id_;
+        return true;
+      }
+      return false;
     case GL_ACTIVE_TEXTURE:
       *params = active_texture_unit_ + GL_TEXTURE0;
       return true;
@@ -1491,6 +1507,31 @@ void GLES2Implementation::BufferDataHelper(
     return;
   }
 
+  switch (target) {
+  case GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM:

[greggman, 2012/05/24 20:56:00]

style: case is indented from switch

+  case GL_PIXEL_UNPACK_TRANSFER_BUFFER_CHROMIUM: {
+    GLuint buffer_id = target != GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM ?
+        bound_pixel_unpack_transfer_buffer_id_ :
+        bound_pixel_pack_transfer_buffer_id_;
+    if (!buffer_id) {
+      SetGLError(GL_INVALID_VALUE, "glBufferData: unknown buffer");
+      return;
+    }
+    // Remove old buffer.
+    buffer_tracker_->RemoveBuffer(buffer_id);

[greggman, 2012/05/24 20:56:00]

Should this happen inside buffer_tracker as in something like
buffer_tracker_->ResizeBuffer or AllocateBuffer ?  It seems like it would be
nice to avoid reallocation if the buffer is the same size. 

[reveman, 2012/05/25 15:45:10]

I agree. will fix this.

+
+    // Creat new buffer.
+    BufferTracker::Buffer* buffer = buffer_tracker_->CreateBuffer(
+        buffer_id, size);
+    GPU_DCHECK(buffer);
+    if (data)
+      memcpy(buffer->address(), data, size);
+    helper_->BufferData(
+        target, size, buffer->shm_id(), buffer->shm_offset(), usage);
+    return;
+  } break;
+  }
+
   // If there is no data just send BufferData
   if (!data) {
     helper_->BufferData(target, size, 0, 0, usage);
@@ -1769,6 +1810,13 @@ void GLES2Implementation::TexSubImage2D(
     return;
   }
 
+  if (bound_pixel_unpack_transfer_buffer_id_) {
+    helper_->TexSubImage2D(
+        target, level, xoffset, yoffset, width, height, format, type,
+        0, ToGLuint(pixels), false);
+    return;
+  }
+
   uint32 temp_size;
   uint32 unpadded_row_size;
   uint32 padded_row_size;
@@ -2292,6 +2340,12 @@ void GLES2Implementation::BindBufferHelper(
     case GL_ELEMENT_ARRAY_BUFFER:
       bound_element_array_buffer_id_ = buffer;
       break;
+    case GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM:
+      bound_pixel_pack_transfer_buffer_id_ = buffer;
+      break;
+    case GL_PIXEL_UNPACK_TRANSFER_BUFFER_CHROMIUM:
+      bound_pixel_unpack_transfer_buffer_id_ = buffer;
+      break;
     default:
       break;
   }
@@ -2643,12 +2697,29 @@ void* GLES2Implementation::MapBufferSubDataCHROMIUM(
     SetGLError(GL_INVALID_VALUE, "MapBufferSubDataCHROMIUM: bad range");
     return NULL;
   }
-  int32 shm_id;
-  unsigned int shm_offset;
-  void* mem = mapped_memory_->Alloc(size, &shm_id, &shm_offset);
-  if (!mem) {
-    SetGLError(GL_OUT_OF_MEMORY, "MapBufferSubDataCHROMIUM: out of memory");
-    return NULL;
+  int32 shm_id = 0;
+  unsigned int shm_offset = 0;
+  void* mem = 0;
+  switch (target) {
+  case GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM:

[greggman, 2012/05/24 20:56:00]

style: indent

+  case GL_PIXEL_UNPACK_TRANSFER_BUFFER_CHROMIUM: {
+    BufferTracker::Buffer* buffer = buffer_tracker_->GetBuffer(
+        target == GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM ?
+        bound_pixel_pack_transfer_buffer_id_ :
+        bound_pixel_unpack_transfer_buffer_id_);
+    if (!buffer) {
+      SetGLError(GL_INVALID_VALUE, "MapBufferSubDataCHROMIUM: invalid buffer");
+      return NULL;
+    }
+    mem = static_cast<uint8*>(buffer->address()) + offset;
+  } break;

[greggman, 2012/05/24 20:56:00]

style: breaks go inside case blocks

[greggman, 2012/05/24 20:56:00]

style: break goes inside case block

+  default:
+    mem = mapped_memory_->Alloc(size, &shm_id, &shm_offset);
+    if (!mem) {
+      SetGLError(GL_OUT_OF_MEMORY, "MapBufferSubDataCHROMIUM: out of memory");
+      return NULL;
+    }
+    break;
   }
 
   std::pair<MappedBufferMap::iterator, bool> result =
@@ -2672,15 +2743,22 @@ void GLES2Implementation::UnmapBufferSubDataCHROMIUM(const void* mem) {
     return;
   }
   const MappedBuffer& mb = it->second;
-  helper_->BufferSubData(
-      mb.target, mb.offset, mb.size, mb.shm_id, mb.shm_offset);
-  mapped_memory_->FreePendingToken(mb.shm_memory, helper_->InsertToken());
-  // Flushing after unmap lets the service side start processing commands
-  // sooner. However, on lowend devices, the thread thrashing causes is
-  // worse than the latency hit.
+  switch (mb.target) {
+  case GL_PIXEL_PACK_TRANSFER_BUFFER_CHROMIUM:

[greggman, 2012/05/24 20:56:00]

indent

+  case GL_PIXEL_UNPACK_TRANSFER_BUFFER_CHROMIUM:
+    break;
+  default:
+    helper_->BufferSubData(
+        mb.target, mb.offset, mb.size, mb.shm_id, mb.shm_offset);
+    mapped_memory_->FreePendingToken(mb.shm_memory, helper_->InsertToken());
+    // Flushing after unmap lets the service side start processing commands
+    // sooner. However, on lowend devices, the thread thrashing causes is
+    // worse than the latency hit.
 #if !defined(OS_ANDROID) && !defined(OS_CHROMEOS)
-  helper_->CommandBufferHelper::Flush();
+    helper_->CommandBufferHelper::Flush();
 #endif
+    break;
+  }
   mapped_buffers_.erase(it);

[greggman, 2012/05/24 20:56:00]

I'm not sure why you'd erase the buffer here but then I guess like you said
you're going to add new entry points instead of using MapSubBuffer and
UnmapSubBuffer

 }