Calling OpenGL from the renderer process.

chrome/gpu/gpu_channel.cc

Index: chrome/gpu/gpu_channel.cc
===================================================================
--- chrome/gpu/gpu_channel.cc	(revision 42644)
+++ chrome/gpu/gpu_channel.cc	(working copy)
@@ -2,6 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#if defined(OS_WIN)
+#include <windows.h>
+#endif
+
 #include "chrome/gpu/gpu_channel.h"
 
 #include "base/command_line.h"
@@ -11,6 +15,7 @@
 #include "base/waitable_event.h"
 #include "build/build_config.h"
 #include "chrome/common/child_process.h"
+#include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/gpu_messages.h"
 #include "chrome/gpu/gpu_thread.h"
@@ -27,44 +32,12 @@
   }
 };
 
-typedef base::hash_map<std::string, scoped_refptr<GpuChannel> >
-    GpuChannelMap;
-
 // How long we wait before releasing the GPU process.
 const int kGpuReleaseTimeMS = 10000;
-
-GpuChannelMap g_gpu_channels;
 }  // namespace anonymous
 
-GpuChannel* GpuChannel::EstablishGpuChannel(int renderer_id) {
-  // Map renderer ID to a (single) channel to that process.
-  std::string channel_name = StringPrintf(
-      "%d.r%d", base::GetCurrentProcId(), renderer_id);
-
-  scoped_refptr<GpuChannel> channel;
-
-  GpuChannelMap::const_iterator iter = g_gpu_channels.find(channel_name);
-  if (iter == g_gpu_channels.end()) {
-    channel = new GpuChannel;
-  } else {
-    channel = iter->second;
-  }
-
-  DCHECK(channel != NULL);
-
-  if (!channel->channel_.get()) {
-    if (channel->Init(channel_name)) {
-      g_gpu_channels[channel_name] = channel;
-    } else {
-      channel = NULL;
-    }
-  }
-
-  return channel.get();
-}
-
-GpuChannel::GpuChannel()
-    : renderer_id_(-1)
+GpuChannel::GpuChannel(int renderer_id)
+    : renderer_id_(renderer_id)
 #if defined(OS_POSIX)
     , renderer_fd_(-1)
 #endif
@@ -141,8 +114,10 @@
 
 void GpuChannel::OnControlMessageReceived(const IPC::Message& msg) {
   IPC_BEGIN_MESSAGE_MAP(GpuChannel, msg)
-    IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateCommandBuffer,
-        OnCreateCommandBuffer)
+    IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateViewCommandBuffer,
+        OnCreateViewCommandBuffer)
+    IPC_MESSAGE_HANDLER(GpuChannelMsg_CreateOffscreenCommandBuffer,
+        OnCreateOffscreenCommandBuffer)
     IPC_MESSAGE_HANDLER(GpuChannelMsg_DestroyCommandBuffer,
         OnDestroyCommandBuffer)
     IPC_MESSAGE_UNHANDLED_ERROR()
@@ -154,19 +129,65 @@
   return ++last_id;
 }
 
-void GpuChannel::OnCreateCommandBuffer(int* route_id) {
+void GpuChannel::OnCreateViewCommandBuffer(gfx::NativeViewId view_id,
+                                           int32* route_id) {
+  *route_id = 0;
+
 #if defined(ENABLE_GPU)
+
+#if defined(OS_WIN)
+  gfx::NativeView view = gfx::NativeViewFromId(view_id);
+
+  // Check that the calling renderer is allowed to render to this window.
+  // TODO(apatrick): consider killing the renderer process rather than failing.
+  int view_renderer_id = reinterpret_cast<int>(
+      GetProp(view, chrome::kChromiumRendererIdProperty));
+  if (view_renderer_id != renderer_id_)
+    return;
+#else
+  // TODO(apatrick): This needs to be something valid for mac and linux.
+  // Offscreen rendering will work on these platforms but not rendering to the
+  // window.
+  DCHECK_EQ(view_id, 0);
+  gfx::NativeView view = 0;
+#endif
+
   *route_id = GenerateRouteID();
   scoped_refptr<GpuCommandBufferStub> stub = new GpuCommandBufferStub(
-      this, *route_id);
+      this, view, NULL, gfx::Size(), 0, *route_id);
   router_.AddRoute(*route_id, stub);
   stubs_[*route_id] = stub;
+#endif  // ENABLE_GPU
+}
+
+void GpuChannel::OnCreateOffscreenCommandBuffer(int32 parent_route_id,
+                                                const gfx::Size& size,
+                                                uint32 parent_texture_id,
+                                                int32* route_id) {
+#if defined(ENABLE_GPU)
+  *route_id = GenerateRouteID();
+  scoped_refptr<GpuCommandBufferStub> parent_stub;
+  if (parent_route_id != 0) {
+    StubMap::iterator it = stubs_.find(parent_route_id);
+    DCHECK(it != stubs_.end());
+    parent_stub = it->second;
+  }
+
+  scoped_refptr<GpuCommandBufferStub> stub = new GpuCommandBufferStub(
+      this,
+      NULL,
+      parent_stub.get(),
+      size,
+      parent_texture_id,
+      *route_id);
+  router_.AddRoute(*route_id, stub);
+  stubs_[*route_id] = stub;
 #else
   *route_id = 0;
 #endif
 }
 
-void GpuChannel::OnDestroyCommandBuffer(int route_id) {
+void GpuChannel::OnDestroyCommandBuffer(int32 route_id) {
 #if defined(ENABLE_GPU)
   StubMap::iterator it = stubs_.find(route_id);
   DCHECK(it != stubs_.end());
@@ -175,8 +196,13 @@
 #endif
 }
 
-bool GpuChannel::Init(const std::string& channel_name) {
-  channel_name_ = channel_name;
+bool GpuChannel::Init() {
+  // Check whether we're already initialized.
+  if (channel_.get())
+    return true;
+
+  // Map renderer ID to a (single) channel to that process.
+  std::string channel_name = GetChannelName();
 #if defined(OS_POSIX)
   // This gets called when the GpuChannel is initially created. At this
   // point, create the socketpair and assign the GPU side FD to the channel
@@ -192,3 +218,7 @@
       ChildProcess::current()->GetShutDownEvent()));
   return true;
 }
+
+std::string GpuChannel::GetChannelName() {
+  return StringPrintf("%d.r%d", base::GetCurrentProcId(), renderer_id_);
+}