Implement WebGL's commit on the main thread

third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp

Index: third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp b/third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp
index 137299ee91d4b4ba89685e00a6a616e0bef09cb3..c4ea45e5f6c355d4350ecffac6712573cf949569 100644
--- a/third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp
+++ b/third_party/WebKit/Source/platform/graphics/OffscreenCanvasFrameDispatcherImpl.cpp
@@ -9,8 +9,11 @@
 #include "cc/quads/render_pass.h"
 #include "cc/quads/shared_quad_state.h"
 #include "cc/quads/solid_color_draw_quad.h"
+#include "cc/quads/texture_draw_quad.h"
+#include "platform/graphics/StaticBitmapImage.h"
 #include "public/platform/InterfaceProvider.h"
 #include "public/platform/Platform.h"
+#include "third_party/khronos/GLES2/gl2.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/gfx/geometry/rect.h"
@@ -27,10 +30,8 @@ OffscreenCanvasFrameDispatcherImpl::OffscreenCanvasFrameDispatcherImpl(uint32_t
     Platform::current()->interfaceProvider()->getInterface(mojo::GetProxy(&m_service));
 }
 
-void OffscreenCanvasFrameDispatcherImpl::dispatchFrame()
+void OffscreenCanvasFrameDispatcherImpl::dispatchFrame(PassRefPtr<StaticBitmapImage> image)
 {
-    // TODO(563852/xlai): Currently this is just a simple solid-color compositor
-    // frame. We need to update this function to extract the image data from canvas.
     cc::CompositorFrame frame;
     frame.metadata.device_scale_factor = 1.0f;
     frame.delegated_frame_data.reset(new cc::DelegatedFrameData);
@@ -43,9 +44,37 @@ void OffscreenCanvasFrameDispatcherImpl::dispatchFrame()
     cc::SharedQuadState* sqs = pass->CreateAndAppendSharedQuadState();
     sqs->SetAll(gfx::Transform(), bounds.size(), bounds, bounds, false, 1.f, SkXfermode::kSrcOver_Mode, 0);
 
-    cc::SolidColorDrawQuad* quad = pass->CreateAndAppendDrawQuad<cc::SolidColorDrawQuad>();
-    const bool forceAntialiasingOff = false;
-    quad->SetNew(sqs, bounds, bounds, SK_ColorGREEN, forceAntialiasingOff);
+    // TODO(xidachen): for now, we just submit a SolidColor frame to compositor in the 2d case,
+    // we should extract data from image.
+    if (!image) {
+        cc::SolidColorDrawQuad* quad = pass->CreateAndAppendDrawQuad<cc::SolidColorDrawQuad>();
+        const bool forceAntialiasingOff = false;
+        quad->SetNew(sqs, bounds, bounds, SK_ColorGREEN, forceAntialiasingOff);
+    } else { // WebGL
+        cc::TransferableResource resource;

[Justin Novosad, 2016/09/09 19:10:51]

Here, we should probably assert that 'image' is gpu-backed

[xidachen, 2016/09/09 19:23:42]

Done.

+        resource.id = image->getTextureId();

[Justin Novosad, 2016/09/09 19:10:50]

I suspect is wrong.  The texture Id is useless outside of the GL context it
belongs to. Are you sure this is what the resource.id field is meant to be used
for?

[xidachen, 2016/09/09 19:23:42]

I am not very sure. I looked at this example:
https://cs.chromium.org/chromium/src/services/ui/demo/bitmap_uploader.cc?q=bi...

In the above example, it kept textureId in a hash map, and call
gl->DeleteTextures(1, &texture_id); in a OnResourcesReturned() function call.

danakj@: comments?

+        resource.format = cc::ResourceFormat::RGBA_8888;

[Justin Novosad, 2016/09/09 19:10:51]

we should be extracting format from 'image' instead of using a hard coded value.

[xidachen, 2016/09/09 19:23:42]

My impression was that this mailbox is a resource from GPU, and that is always
in RGBA_8888 format?

+        resource.filter = GL_LINEAR;

[Justin Novosad, 2016/09/09 19:10:51]

Please add a TODO and create a crbug for this: the filter needs to respect the
image-rendering CSS property of the associated canvas element.

[xidachen, 2016/09/09 19:23:42]

Done.

+        resource.size = gfx::Size(m_width, m_height);
+        resource.mailbox_holder = gpu::MailboxHolder(image->getMailbox(), image->getSyncToken(), GL_TEXTURE_2D);
+        resource.read_lock_fences_enabled = false;
+        resource.is_software = false;
+        resource.is_overlay_candidate = false;
+        frame.delegated_frame_data->resource_list.push_back(std::move(resource));
+
+        cc::TextureDrawQuad* quad = pass->CreateAndAppendDrawQuad<cc::TextureDrawQuad>();
+        gfx::Size rectSize(m_width, m_height);
+
+        const bool needsBlending = true;
+        const bool premultipliedAlpha = true;
+        const gfx::PointF uvTopLeft(0.f, 0.f);
+        const gfx::PointF uvBottomRight(1.f, 1.f);
+        float vertexOpacity[4] = {1.f, 1.f, 1.f, 1.f};
+        const bool yflipped = false;
+        const bool nearestNeighbor = false;

[Justin Novosad, 2016/09/09 19:10:50]

TODO: needs to be true when using style "image-rendering: pixelated"

[xidachen, 2016/09/09 19:23:42]

Done.

+        quad->SetAll(sqs, bounds, bounds, bounds, needsBlending, resource.id, gfx::Size(), premultipliedAlpha,
+            uvTopLeft, uvBottomRight, SK_ColorTRANSPARENT, vertexOpacity, yflipped, nearestNeighbor, false);
+    }
 
     frame.delegated_frame_data->render_pass_list.push_back(std::move(pass));