sync compositor: Software draw

content/renderer/android/synchronous_compositor_proxy.cc

Index: content/renderer/android/synchronous_compositor_proxy.cc
diff --git a/content/renderer/android/synchronous_compositor_proxy.cc b/content/renderer/android/synchronous_compositor_proxy.cc
index bd9fb3556757a1ea00670908f781d2932d87cdac..daeeb2a95cc4570d2706139afc310a96a4a7b427 100644
--- a/content/renderer/android/synchronous_compositor_proxy.cc
+++ b/content/renderer/android/synchronous_compositor_proxy.cc
@@ -5,11 +5,17 @@
 #include "content/renderer/android/synchronous_compositor_proxy.h"
 
 #include "base/auto_reset.h"
+#include "base/memory/shared_memory.h"
 #include "content/common/android/sync_compositor_messages.h"
 #include "content/common/cc_messages.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_sender.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkImageInfo.h"
+#include "third_party/skia/include/core/SkRegion.h"
 #include "ui/events/latency_info.h"
+#include "ui/gfx/skia_util.h"
 
 namespace content {
 
@@ -147,6 +153,7 @@ void SynchronousCompositorProxy::OnMessageReceived(
     IPC_MESSAGE_HANDLER(SyncCompositorMsg_BeginFrame, BeginFrame)
     IPC_MESSAGE_HANDLER(SyncCompositorMsg_ComputeScroll, OnComputeScroll)
     IPC_MESSAGE_HANDLER(SyncCompositorMsg_DemandDrawHw, DemandDrawHw)
+    IPC_MESSAGE_HANDLER(SyncCompositorMsg_DemandDrawSw, DemandDrawSw)
     IPC_MESSAGE_HANDLER(SyncCompositorMsg_UpdateState, ProcessCommonParams)
   IPC_END_MESSAGE_MAP()
 }
@@ -196,6 +203,42 @@ void SynchronousCompositorProxy::DemandDrawHw(
   PopulateCommonParams(common_renderer_params);
 }
 
+void SynchronousCompositorProxy::DemandDrawSw(
+    const SyncCompositorCommonBrowserParams& common_params,
+    const SyncCompositorDemandDrawSwParams& params,
+    bool* result,
+    SyncCompositorCommonRendererParams* common_renderer_params,
+    cc::CompositorFrame* frame) {
+  DCHECK(frame);
+  ProcessCommonParams(common_params);
+  *result = false;  // Early out ok.
+  if (!base::SharedMemory::IsHandleValid(params.shm_handle))
+    return;
+
+  base::SharedMemory shm(params.shm_handle, false);
+  if (!shm.Map(params.size.width() * params.size.height() * 4))

[dcheng, 2015/11/23 23:26:35]

This should probably check for overflow.

[boliu, 2015/11/24 00:16:33]

Done.

+    return;
+  DCHECK(shm.memory());
+
+  SkImageInfo info =
+      SkImageInfo::MakeN32Premul(params.size.width(), params.size.height());
+  SkBitmap bitmap;
+  if (!bitmap.installPixels(info, shm.memory(), params.size.width() * 4))

[dcheng, 2015/11/23 23:26:35]

As should this.

[boliu, 2015/11/24 00:16:33]

Done.

+    return;
+  SkCanvas canvas(bitmap);
+  canvas.setMatrix(params.transform.matrix());
+  canvas.setClipRegion(SkRegion(gfx::RectToSkIRect(params.clip)));
+
+  scoped_ptr<cc::CompositorFrame> frame_ptr =
+      output_surface_->DemandDrawSw(&canvas);
+  if (frame_ptr) {
+    *result = true;
+    frame_ptr->AssignTo(frame);
+    DeliverMessages();
+  }
+  PopulateCommonParams(common_renderer_params);
+}
+
 void SynchronousCompositorProxy::OnComputeScroll(
     const SyncCompositorCommonBrowserParams& common_params,
     base::TimeTicks animation_time,