Decoupling backbuffer allocation suggestion from frontbuffer allocation suggestion.

content/common/gpu/image_transport_surface_linux.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/gpu/image_transport_surface.h"
 
 // This conflicts with the defines in Xlib.h and must come first.
 #include "content/common/gpu/gpu_messages.h"
 
 #include <map>
@@ skipping 75 matching lines @@
   // gfx::GLSurface implementation
   virtual bool Initialize() OVERRIDE;
   virtual void Destroy() OVERRIDE;
   virtual bool IsOffscreen() OVERRIDE;
   virtual bool SwapBuffers() OVERRIDE;
   virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
   virtual std::string GetExtensions() OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual bool OnMakeCurrent(gfx::GLContext* context) OVERRIDE;
   virtual unsigned int GetBackingFrameBufferObject() OVERRIDE;
-  virtual void SetBufferAllocation(BufferAllocationState state) OVERRIDE;
+  virtual void SetBackbufferAllocation(bool allocated) OVERRIDE;
+  virtual void SetFrontbufferAllocation(bool allocated) OVERRIDE;
 
  protected:
   // ImageTransportSurface implementation
   virtual void OnNewSurfaceACK(
       uint64 surface_handle, TransportDIB::Handle shm_handle) OVERRIDE;
   virtual void OnBuffersSwappedACK() OVERRIDE;
   virtual void OnPostSubBufferACK() OVERRIDE;
   virtual void OnResizeViewACK() OVERRIDE;
   virtual void OnResize(gfx::Size size) OVERRIDE;
 
  private:
   virtual ~EGLImageTransportSurface() OVERRIDE;
   void ReleaseSurface(scoped_refptr<EGLAcceleratedSurface>* surface);
   void SendBuffersSwapped();
   void SendPostSubBuffer(int x, int y, int width, int height);
 
   // Tracks the current buffer allocation state.
-  BufferAllocationState buffer_allocation_state_;
+  bool backbuffer_suggested_allocation_;
+  bool frontbuffer_suggested_allocation_;
+
+  // The expected size when visible.
+  gfx::Size visible_size_;
 
   uint32 fbo_id_;
 
   scoped_refptr<EGLAcceleratedSurface> back_surface_;
   scoped_refptr<EGLAcceleratedSurface> front_surface_;
   gfx::Rect previous_damage_rect_;
 
   // Whether or not we've successfully made the surface current once.
   bool made_current_;
 
@@ skipping 13 matching lines @@
                            GpuCommandBufferStub* stub);
 
   // gfx::GLSurface implementation:
   virtual bool Initialize() OVERRIDE;
   virtual void Destroy() OVERRIDE;
   virtual bool SwapBuffers() OVERRIDE;
   virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
   virtual std::string GetExtensions();
   virtual gfx::Size GetSize() OVERRIDE;
   virtual bool OnMakeCurrent(gfx::GLContext* context) OVERRIDE;
-  virtual void SetBufferAllocation(BufferAllocationState state) OVERRIDE;
+  virtual void SetBackbufferAllocation(bool allocated) OVERRIDE;
+  virtual void SetFrontbufferAllocation(bool allocated) OVERRIDE;
 
  protected:
   // ImageTransportSurface implementation:
   virtual void OnNewSurfaceACK(
       uint64 surface_handle, TransportDIB::Handle shm_handle) OVERRIDE;
   virtual void OnBuffersSwappedACK() OVERRIDE;
   virtual void OnPostSubBufferACK() OVERRIDE;
   virtual void OnResizeViewACK() OVERRIDE;
   virtual void OnResize(gfx::Size size) OVERRIDE;
 
  private:
   virtual ~GLXImageTransportSurface();
 
   // Tell the browser to release the surface.
   void ReleaseSurface();
 
   void SendBuffersSwapped();
   void SendPostSubBuffer(int x, int y, int width, int height);
 
   void ResizeSurface(gfx::Size size);
 
   // Tracks the current buffer allocation state.
-  BufferAllocationState buffer_allocation_state_;
+  bool backbuffer_suggested_allocation_;
+  bool frontbuffer_suggested_allocation_;
 
   XID dummy_parent_;
   gfx::Size size_;
 
   // Whether or not the image has been bound on the browser side.
   bool bound_;
 
   // Whether or not we need to send a resize on the next swap.
   bool needs_resize_;
 
@@ skipping 81 matching lines @@
 EGLAcceleratedSurface::~EGLAcceleratedSurface() {
   glDeleteTextures(1, &texture_);
   eglDestroyImageKHR(gfx::GLSurfaceEGL::GetHardwareDisplay(), image_);
   XFreePixmap(gfx::GLSurfaceEGL::GetNativeDisplay(), pixmap_);
 }
 
 EGLImageTransportSurface::EGLImageTransportSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub)
     : gfx::PbufferGLSurfaceEGL(false, gfx::Size(16, 16)),
-      buffer_allocation_state_(BUFFER_ALLOCATION_FRONT_AND_BACK),
+      backbuffer_suggested_allocation_(true),
+      frontbuffer_suggested_allocation_(true),
       fbo_id_(0),
       made_current_(false) {
   helper_.reset(new ImageTransportHelper(this,
                                          manager,
                                          stub,
                                          gfx::kNullPluginWindow));
 }
 
 EGLImageTransportSurface::~EGLImageTransportSurface() {
   Destroy();
@@ skipping 45 matching lines @@
   }
 
   made_current_ = true;
   return true;
 }
 
 unsigned int EGLImageTransportSurface::GetBackingFrameBufferObject() {
   return fbo_id_;
 }
 
-void EGLImageTransportSurface::SetBufferAllocation(
-    BufferAllocationState state) {
-  if (buffer_allocation_state_ == state)
+void EGLImageTransportSurface::SetBackbufferAllocation(bool allocated) {
+  if (backbuffer_suggested_allocation_ == allocated)
     return;
-  buffer_allocation_state_ = state;
+  backbuffer_suggested_allocation_ = allocated;
 
-  switch (state) {
-    case BUFFER_ALLOCATION_FRONT_AND_BACK:
-      if (!back_surface_.get() && front_surface_.get())
-        OnResize(front_surface_->size());
-      break;
+  if (!!back_surface_.get() != backbuffer_suggested_allocation_) {

[jonathan.backer, 2012/05/11 18:43:15]

This check seems redundant (just testing my understanding). Don't we always act
immediately?

[mmocny, 2012/05/14 17:10:36]

Yes, you are right.
On 2012/05/11 18:43:15, jonathan.backer wrote:

+    if (backbuffer_suggested_allocation_)
+      OnResize(visible_size_);
+    else
+      ReleaseSurface(&back_surface_);
+  }
+}
 
-    case BUFFER_ALLOCATION_FRONT_ONLY:
-      if (back_surface_.get() && front_surface_.get())
-        ReleaseSurface(&back_surface_);
-      break;
-
-    case BUFFER_ALLOCATION_NONE:
-      if (back_surface_.get() && front_surface_.get())
-        ReleaseSurface(&back_surface_);
-      break;
-
-    default:
-      NOTREACHED();
-  }
+void EGLImageTransportSurface::SetFrontbufferAllocation(bool allocated) {
+  if (frontbuffer_suggested_allocation_ == allocated)
+    return;
+  frontbuffer_suggested_allocation_ = allocated;

[jonathan.backer, 2012/05/11 18:43:15]

Can we release the frontbuffer here?

[mmocny, 2012/05/14 17:10:36]

We can -- but that should be a subsequent patch, right?
On 2012/05/11 18:43:15, jonathan.backer wrote:

 }
 
 void EGLImageTransportSurface::ReleaseSurface(
     scoped_refptr<EGLAcceleratedSurface>* surface) {
   if (surface->get()) {
     GpuHostMsg_AcceleratedSurfaceRelease_Params params;
     params.identifier = (*surface)->pixmap();
     helper_->SendAcceleratedSurfaceRelease(params);
     *surface = NULL;
   }
 }
 
 void EGLImageTransportSurface::OnResize(gfx::Size size) {
+  visible_size_ = size;
   back_surface_ = new EGLAcceleratedSurface(size);
 
   GLint previous_fbo_id = 0;
   glGetIntegerv(GL_FRAMEBUFFER_BINDING, &previous_fbo_id);
 
   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo_id_);
   glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
                             GL_COLOR_ATTACHMENT0,
                             GL_TEXTURE_2D,
                             back_surface_->texture(),
                             0);
   glFlush();
 
   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, previous_fbo_id);
 
   GpuHostMsg_AcceleratedSurfaceNew_Params params;
   params.width = size.width();
   params.height = size.height();
   params.surface_handle = back_surface_->pixmap();
   helper_->SendAcceleratedSurfaceNew(params);
 
   helper_->SetScheduled(false);
 }
 
 bool EGLImageTransportSurface::SwapBuffers() {
+  DCHECK(backbuffer_suggested_allocation_);
+  DCHECK(frontbuffer_suggested_allocation_);
   front_surface_.swap(back_surface_);
   DCHECK_NE(front_surface_.get(), static_cast<EGLAcceleratedSurface*>(NULL));
   helper_->DeferToFence(base::Bind(
       &EGLImageTransportSurface::SendBuffersSwapped,
       AsWeakPtr()));
 
   gfx::Size expected_size = front_surface_->size();
   if (!back_surface_.get() || back_surface_->size() != expected_size) {
     OnResize(expected_size);
   } else {
     glFramebufferTexture2DEXT(GL_FRAMEBUFFER,
                               GL_COLOR_ATTACHMENT0,
                               GL_TEXTURE_2D,
                               back_surface_->texture(),
                               0);
   }
   previous_damage_rect_ = gfx::Rect(front_surface_->size());
   return true;
 }
 
 void EGLImageTransportSurface::SendBuffersSwapped() {
   GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
   params.surface_handle = front_surface_->pixmap();
   helper_->SendAcceleratedSurfaceBuffersSwapped(params);
   helper_->SetScheduled(false);
 }
 
 bool EGLImageTransportSurface::PostSubBuffer(
     int x, int y, int width, int height) {
-
+  DCHECK(backbuffer_suggested_allocation_);
+  DCHECK(frontbuffer_suggested_allocation_);
   DCHECK_NE(back_surface_.get(), static_cast<EGLAcceleratedSurface*>(NULL));
   gfx::Size expected_size = back_surface_->size();
   bool surfaces_same_size = front_surface_.get() &&
       front_surface_->size() == expected_size;
 
   const gfx::Rect new_damage_rect(x, y, width, height);
 
   // An empty damage rect is a successful no-op.
   if (new_damage_rect.IsEmpty())
     return true;
@@ skipping 78 matching lines @@
 }
 
 void EGLImageTransportSurface::OnResizeViewACK() {
   NOTREACHED();
 }
 
 GLXImageTransportSurface::GLXImageTransportSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub)
     : gfx::NativeViewGLSurfaceGLX(),
-      buffer_allocation_state_(BUFFER_ALLOCATION_FRONT_AND_BACK),
+      backbuffer_suggested_allocation_(true),
+      frontbuffer_suggested_allocation_(true),
       dummy_parent_(0),
       size_(1, 1),
       bound_(false),
       needs_resize_(false),
       made_current_(false) {
   helper_.reset(new ImageTransportHelper(this,
                                          manager,
                                          stub,
                                          gfx::kNullPluginWindow));
 }
@@ skipping 63 matching lines @@
 }
 
 void GLXImageTransportSurface::ReleaseSurface() {
   DCHECK(bound_);
   GpuHostMsg_AcceleratedSurfaceRelease_Params params;
   params.identifier = window_;
   helper_->SendAcceleratedSurfaceRelease(params);
   bound_ = false;
 }
 
-void GLXImageTransportSurface::SetBufferAllocation(
-    BufferAllocationState state) {
-  if (buffer_allocation_state_ == state)
+void GLXImageTransportSurface::SetBackbufferAllocation(bool allocated) {
+  if (backbuffer_suggested_allocation_ == allocated)
     return;
-  buffer_allocation_state_ = state;
+  backbuffer_suggested_allocation_ = allocated;
 
-  switch (state) {
-    case BUFFER_ALLOCATION_FRONT_AND_BACK: {
-      ResizeSurface(size_);
-      break;
-    }
-    case BUFFER_ALLOCATION_FRONT_ONLY: {
-      ResizeSurface(gfx::Size(1,1));
-      break;
-    }
-    case BUFFER_ALLOCATION_NONE: {
-      ResizeSurface(gfx::Size(1,1));
-      if (bound_)
-        ReleaseSurface();
-      break;
-    }
-    default:
-      NOTREACHED();
-  }
+  if (backbuffer_suggested_allocation_)
+    ResizeSurface(size_);
+  else
+    ResizeSurface(gfx::Size(1,1));
+}
+
+void GLXImageTransportSurface::SetFrontbufferAllocation(bool allocated) {
+  if (frontbuffer_suggested_allocation_ == allocated)
+    return;
+  frontbuffer_suggested_allocation_ = allocated;
+
+  // We recreate frontbuffer by recreating backbuffer and swapping.
+  // But we release frontbuffer by telling UI to release its handle on it.
+  if (!frontbuffer_suggested_allocation_ && bound_)
+    ReleaseSurface();
 }
 
 void GLXImageTransportSurface::ResizeSurface(gfx::Size size) {
   Display* dpy = static_cast<Display*>(GetDisplay());
   XResizeWindow(dpy, window_, size.width(), size.height());
   glXWaitX();
   // Seems necessary to perform a swap after a resize
   // in order to resize the front and back buffers (Intel driver bug).
   // This doesn't always happen with scissoring enabled, so do it now.
   if (gfx::g_GLX_MESA_copy_sub_buffer && gfx::GLSurface::GetCurrent() == this)
     gfx::NativeViewGLSurfaceGLX::SwapBuffers();
   needs_resize_ = true;
 }
 
 void GLXImageTransportSurface::OnResize(gfx::Size size) {
   TRACE_EVENT0("gpu", "GLXImageTransportSurface::OnResize");
   size_ = size;
   ResizeSurface(size_);
 }
 
 bool GLXImageTransportSurface::SwapBuffers() {
+  DCHECK(backbuffer_suggested_allocation_);
+  DCHECK(frontbuffer_suggested_allocation_);
   gfx::NativeViewGLSurfaceGLX::SwapBuffers();
   helper_->DeferToFence(base::Bind(
       &GLXImageTransportSurface::SendBuffersSwapped,
       AsWeakPtr()));
 
   if (needs_resize_) {
     GpuHostMsg_AcceleratedSurfaceNew_Params params;
     params.width = size_.width();
     params.height = size_.height();
     params.surface_handle = window_;
     helper_->SendAcceleratedSurfaceNew(params);
     bound_ = true;
     needs_resize_ = false;
   }
   return true;
 }
 
 void GLXImageTransportSurface::SendBuffersSwapped() {
   GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params params;
   params.surface_handle = window_;
   helper_->SendAcceleratedSurfaceBuffersSwapped(params);
   helper_->SetScheduled(false);
 }
 
 bool GLXImageTransportSurface::PostSubBuffer(
     int x, int y, int width, int height) {
+  DCHECK(backbuffer_suggested_allocation_);
+  DCHECK(frontbuffer_suggested_allocation_);
   gfx::NativeViewGLSurfaceGLX::PostSubBuffer(x, y, width, height);
   helper_->DeferToFence(base::Bind(
       &GLXImageTransportSurface::SendPostSubBuffer,
       AsWeakPtr(), x, y, width, height));
 
   if (needs_resize_) {
     GpuHostMsg_AcceleratedSurfaceNew_Params params;
     params.width = size_.width();
     params.height = size_.height();
     params.surface_handle = window_;
@@ skipping 244 matching lines @@
                                                    stub,
                                                    surface.get(),
                                                    handle.transport);
   }
 
   if (surface->Initialize())
     return surface;
   else
     return NULL;
 }