Surfaceless OutputSurface implementation.

content/browser/compositor/gpu_browser_compositor_output_surface.cc

Index: content/browser/compositor/gpu_browser_compositor_output_surface.cc
diff --git a/content/browser/compositor/gpu_browser_compositor_output_surface.cc b/content/browser/compositor/gpu_browser_compositor_output_surface.cc
index 3b79d546d4272f4c8608f441e81879faf3d86ed8..054d1a63e00bd12099fcce0622042e1f4a54fe89 100644
--- a/content/browser/compositor/gpu_browser_compositor_output_surface.cc
+++ b/content/browser/compositor/gpu_browser_compositor_output_surface.cc
@@ -6,7 +6,9 @@
 
 #include "cc/output/compositor_frame.h"
 #include "content/browser/compositor/reflector_impl.h"
+#include "content/browser/gpu/gpu_surface_tracker.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
+#include "gpu/GLES2/gl2extchromium.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 
 namespace content {
@@ -49,4 +51,194 @@ void GpuBrowserCompositorOutputSurface::SwapBuffers(
   OutputSurface::SwapBuffers(frame);
 }
 
+GpuSurfacelessBrowserCompositorOutputSurface::
+    GpuSurfacelessBrowserCompositorOutputSurface(
+        const scoped_refptr<ContextProviderCommandBuffer>& context,
+        int surface_id,
+        IDMap<BrowserCompositorOutputSurface>* output_surface_map,
+        const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager,
+        scoped_ptr<cc::OverlayCandidateValidator> overlay_candidate_validator,
+        unsigned internalformat,
+        int z_order)

[alexst (slow to review), 2014/09/02 13:15:59]

I see primary surface as always being 0, others can allocate around it with
negative indices.

[achaulk, 2014/09/02 17:48:44]

I just made this configurable so that if someone did want to do a multiple
compositor thing they can set up the levels the way they want

+    : GpuBrowserCompositorOutputSurface(context,
+                                        surface_id,
+                                        output_surface_map,
+                                        vsync_manager,
+                                        overlay_candidate_validator.Pass()),
+      z_order_(z_order),
+      expects_pageflip_messages_(false),

[alexst (slow to review), 2014/09/02 13:15:59]

Please provide a way to change this.

[achaulk, 2014/09/02 17:48:44]

That will be when the IPC gets integrated

+      internalformat_(internalformat) {
+}
+
+GpuSurfacelessBrowserCompositorOutputSurface::
+    ~GpuSurfacelessBrowserCompositorOutputSurface() {
+}
+
+void GpuSurfacelessBrowserCompositorOutputSurface::SwapBuffers(
+    cc::CompositorFrame* frame) {
+  DCHECK(output_surface_);
+  output_surface_->SwapBuffers();
+
+  const gfx::Rect& rect = frame->gl_frame_data->sub_buffer_rect;

[alexst (slow to review), 2014/09/02 13:15:59]

sub_buffer_rect provides a dirty region, if I am not mistaken. It will only be
smaller than the whole frame size if partial swap is enabled. This should use
size, and the rect will be used when we implement partial updates.

[achaulk, 2014/09/02 17:48:44]

Sure. I'm not sure how we can really do partial updates anyway. Maybe only every
other frame and keep old buffers around?

+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->Finish();
+  gl->ScheduleOverlayPlaneCHROMIUM(z_order_,
+                                   GL_OVERLAY_TRANSFORM_NONE_CHROMIUM,
+                                   output_surface_->tex_id(),
+                                   rect.x(),
+                                   rect.y(),
+                                   rect.width(),
+                                   rect.height(),
+                                   0,
+                                   0,
+                                   1.0f,
+                                   1.0f);
+  GpuBrowserCompositorOutputSurface::SwapBuffers(frame);
+}
+
+void GpuSurfacelessBrowserCompositorOutputSurface::OnSwapBuffersComplete() {
+  DCHECK(output_surface_);
+  // PageFlipComplete must be called to properly drive the buffering. If we
+  // don't expect to receive these calls from IPCs, we should call it here.
+  if (!expects_pageflip_messages_)
+    output_surface_->PageFlipComplete();
+  GpuBrowserCompositorOutputSurface::OnSwapBuffersComplete();
+}
+
+void GpuSurfacelessBrowserCompositorOutputSurface::BindFramebuffer() {
+  DCHECK(output_surface_);
+  output_surface_->BindFramebuffer();
+}
+
+void GpuSurfacelessBrowserCompositorOutputSurface::Reshape(
+    const gfx::Size& size,
+    float scale_factor) {
+  gfx::Size current = SurfaceSize();
+  GpuBrowserCompositorOutputSurface::Reshape(size, scale_factor);
+  DCHECK(output_surface_);
+  output_surface_->Reshape(SurfaceSize(), scale_factor);
+}
+
+bool GpuSurfacelessBrowserCompositorOutputSurface::BindToClient(
+    cc::OutputSurfaceClient* client) {
+  DCHECK(output_surface_);
+  if (!GpuBrowserCompositorOutputSurface::BindToClient(client))
+    return false;
+  if (!output_surface_) {
+    output_surface_.reset(
+        new BufferedOutputSurface(context_provider_, internalformat_));
+  }
+  return true;
+}
+
+BufferedOutputSurface::BufferedOutputSurface(
+    scoped_refptr<cc::ContextProvider> context_provider,
+    unsigned int internalformat)
+    : context_provider_(context_provider),
+      fbo_(0),
+      depth_rb_(0),
+      tex_id_(0),
+      internalformat_(internalformat),
+      current_surface_(0),
+      last_surface_(0),
+      available_surface_(0),
+      in_flight_surface_(0) {
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();

[alexst (slow to review), 2014/09/02 13:15:59]

Please split all the GL code from the constructor into an init function.

[achaulk, 2014/09/02 17:48:44]

Done.

+  gl->GenFramebuffers(1, &fbo_);
+  gl->GenRenderbuffers(1, &depth_rb_);
+  gl->GenTextures(1, &tex_id_);
+  DCHECK(fbo_);
+  DCHECK(depth_rb_);
+  DCHECK(tex_id_);
+}
+
+BufferedOutputSurface::~BufferedOutputSurface() {
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  if (fbo_)
+    gl->DeleteFramebuffers(1, &fbo_);
+  if (depth_rb_)
+    gl->DeleteRenderbuffers(1, &depth_rb_);
+  if (tex_id_)
+    gl->DeleteTextures(1, &tex_id_);
+  FreeAllSurfaces();
+}
+
+void BufferedOutputSurface::BindFramebuffer() {
+  if (!current_surface_)
+    current_surface_ = GetNextSurface();
+
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->BindFramebuffer(GL_FRAMEBUFFER, fbo_);
+  gl->BindTexture(GL_TEXTURE_2D, tex_id_);
+  gl->BindTexImage2DCHROMIUM(GL_TEXTURE_2D, current_surface_);
+  gl->FramebufferTexture2D(
+      GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex_id_, 0);
+}
+
+void BufferedOutputSurface::SwapBuffers() {
+  if (last_surface_) {
+    if (in_flight_surface_)
+      context_provider_->ContextGL()->DestroyImageCHROMIUM(in_flight_surface_);
+    else
+      in_flight_surface_ = last_surface_;
+  }
+  last_surface_ = current_surface_;
+  current_surface_ = 0;
+}
+
+void BufferedOutputSurface::Reshape(const gfx::Size& size, float scale_factor) {
+  if (size == size_)
+    return;
+  size_ = size;
+  FreeAllSurfaces();
+
+  if (size_.width() == 0 || size_.height() == 0)
+    return;  // Nothing to do.
+  gpu::gles2::GLES2Interface* gl = context_provider_->ContextGL();
+  gl->BindFramebuffer(GL_FRAMEBUFFER, fbo_);
+  gl->BindRenderbuffer(GL_RENDERBUFFER, depth_rb_);
+  gl->RenderbufferStorage(
+      GL_RENDERBUFFER, GL_DEPTH_COMPONENT24_OES, size_.width(), size_.height());
+  gl->FramebufferRenderbuffer(
+      GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth_rb_);
+}
+
+void BufferedOutputSurface::PageFlipComplete() {
+  if (!available_surface_)
+    available_surface_ = in_flight_surface_;
+  else
+    context_provider_->ContextGL()->DestroyImageCHROMIUM(in_flight_surface_);
+  in_flight_surface_ = 0;
+}
+
+void BufferedOutputSurface::FreeAllSurfaces() {
+  FreeSurface(&in_flight_surface_);
+  FreeSurface(&available_surface_);
+  FreeSurface(&last_surface_);
+  FreeSurface(&current_surface_);
+}
+
+void BufferedOutputSurface::FreeSurface(unsigned int* surface) {
+  if (*surface) {
+    context_provider_->ContextGL()->DestroyImageCHROMIUM(*surface);
+    *surface = 0;
+  }
+}
+
+unsigned int BufferedOutputSurface::GetNextSurface() {
+  if (available_surface_) {
+    unsigned int id = available_surface_;
+    available_surface_ = 0;
+    return id;
+  }
+
+  unsigned int id = context_provider_->ContextGL()->CreateImageCHROMIUM(

[alexst (slow to review), 2014/09/02 13:15:59]

Allocating these involves a sync IPC, and I would also like to reduce the churn
of new buffers, so We should re-use as much as possible, and should only be
deleting these buffers when we are reshaping and during teardown.

[achaulk, 2014/09/02 17:48:44]

I can make it keep the third buffer around instead of reducing to two ASAP, but
I don't think we want to keep the extra buffers in the degenerate N-buffer case
where page flip messages are delayed. We might not have the memory for a half
dozen framebuffers anyway

+      size_.width(),
+      size_.height(),
+      internalformat_,
+      GL_IMAGE_SCANOUT_CHROMIUM);
+  DCHECK(id);
+  return id;
+}
+
 }  // namespace content