Lazy initialize WGC3DInProcessCommandBufferImpl

webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.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 "webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.h"
 
 #include <GLES2/gl2.h>
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES 1
 #endif
@@ skipping 526 matching lines @@
   }
 }
 
 void GLInProcessContext::OnContextLost() {
   if (!context_lost_callback_.is_null())
     context_lost_callback_.Run();
 }
 
 WebGraphicsContext3DInProcessCommandBufferImpl::
     WebGraphicsContext3DInProcessCommandBufferImpl()
-    : context_(NULL),
+    : pending_lazy_initialize_(false),
+      context_(NULL),
       gl_(NULL),
       context_lost_callback_(NULL),
       context_lost_reason_(GL_NO_ERROR),
       cached_width_(0),
       cached_height_(0),
       bound_fbo_(0) {
 }
 
 WebGraphicsContext3DInProcessCommandBufferImpl::
     ~WebGraphicsContext3DInProcessCommandBufferImpl() {
   base::AutoLock a(g_all_shared_contexts_lock.Get());
   g_all_shared_contexts.Pointer()->erase(this);
 }
 
 bool WebGraphicsContext3DInProcessCommandBufferImpl::Initialize(
-    WebGraphicsContext3D::Attributes attributes,
-    WebKit::WebGraphicsContext3D* view_context) {
+    const WebGraphicsContext3D::Attributes& attributes) {
+  attributes_ = attributes;
+  pending_lazy_initialize_ = true;
+  return true;

[piman, 2013/03/21 22:29:11]

If Initialize doesn't do anything any more and can't return failure, we should
simply fold it into the constructor.

[boliu, 2013/03/21 22:53:23]

Done.

+}
+
+bool WebGraphicsContext3DInProcessCommandBufferImpl::DoInitialize() {
+  DCHECK(pending_lazy_initialize_);
+
   // Convert WebGL context creation attributes into GLInProcessContext / EGL
   // size requests.
-  const int alpha_size = attributes.alpha ? 8 : 0;
-  const int depth_size = attributes.depth ? 24 : 0;
-  const int stencil_size = attributes.stencil ? 8 : 0;
-  const int samples = attributes.antialias ? 4 : 0;
-  const int sample_buffers = attributes.antialias ? 1 : 0;
+  const int alpha_size = attributes_.alpha ? 8 : 0;
+  const int depth_size = attributes_.depth ? 24 : 0;
+  const int stencil_size = attributes_.stencil ? 8 : 0;
+  const int samples = attributes_.antialias ? 4 : 0;
+  const int sample_buffers = attributes_.antialias ? 1 : 0;
   const int32 attribs[] = {
     GLInProcessContext::ALPHA_SIZE, alpha_size,
     GLInProcessContext::DEPTH_SIZE, depth_size,
     GLInProcessContext::STENCIL_SIZE, stencil_size,
     GLInProcessContext::SAMPLES, samples,
     GLInProcessContext::SAMPLE_BUFFERS, sample_buffers,
     GLInProcessContext::NONE,
   };
 
   const char* preferred_extensions = "*";
 
   // TODO(kbr): More work will be needed in this implementation to
   // properly support GPU switching. Like in the out-of-process
   // command buffer implementation, all previously created contexts
   // will need to be lost either when the first context requesting the
   // discrete GPU is created, or the last one is destroyed.
   gfx::GpuPreference gpu_preference = gfx::PreferDiscreteGpu;
 
-  GLInProcessContext* parent_context = NULL;
-  if (view_context) {
-    WebGraphicsContext3DInProcessCommandBufferImpl* context_impl =
-        static_cast<WebGraphicsContext3DInProcessCommandBufferImpl*>(
-            view_context);
-    parent_context = context_impl->context_;
-  }
-
   WebGraphicsContext3DInProcessCommandBufferImpl* context_group = NULL;
   base::AutoLock lock(g_all_shared_contexts_lock.Get());
-  if (attributes.shareResources)
+  if (attributes_.shareResources)
     context_group = g_all_shared_contexts.Pointer()->empty() ?
         NULL : *g_all_shared_contexts.Pointer()->begin();
 
   context_ = GLInProcessContext::CreateOffscreenContext(
-      parent_context,
+      NULL,

[piman, 2013/03/21 22:29:11]

note: if we don't use parenting here any more, there's a bunch of code I think
we can rip out.

[boliu, 2013/03/21 22:53:23]

Done.

       gfx::Size(1, 1),
       context_group ? context_group->context_ : NULL,
       preferred_extensions,
       attribs,
       gpu_preference);
 
   if (!context_)
     return false;
 
   gl_ = context_->GetImplementation();
 
-  if (gl_ && attributes.noExtensions)
+  if (gl_ && attributes_.noExtensions)
     gl_->EnableFeatureCHROMIUM("webgl_enable_glsl_webgl_validation");
 
   context_->SetContextLostCallback(
       base::Bind(
           &WebGraphicsContext3DInProcessCommandBufferImpl::OnContextLost,
           base::Unretained(this)));
 
   // Set attributes_ from created offscreen context.
   {
-    attributes_ = attributes;
     GLint alpha_bits = 0;
     getIntegerv(GL_ALPHA_BITS, &alpha_bits);
     attributes_.alpha = alpha_bits > 0;
     GLint depth_bits = 0;
     getIntegerv(GL_DEPTH_BITS, &depth_bits);
     attributes_.depth = depth_bits > 0;
     GLint stencil_bits = 0;
     getIntegerv(GL_STENCIL_BITS, &stencil_bits);
     attributes_.stencil = stencil_bits > 0;
     GLint sample_buffers = 0;
     getIntegerv(GL_SAMPLE_BUFFERS, &sample_buffers);
     attributes_.antialias = sample_buffers > 0;
   }
-  makeContextCurrent();
 
-  if (attributes.shareResources)
+  if (attributes_.shareResources)
     g_all_shared_contexts.Pointer()->insert(this);
 
+  pending_lazy_initialize_ = false;
   return true;
 }
 
 bool WebGraphicsContext3DInProcessCommandBufferImpl::makeContextCurrent() {
+  if (pending_lazy_initialize_ && !DoInitialize())
+    return false;
+
   return GLInProcessContext::MakeCurrent(context_);
 }
 
 void WebGraphicsContext3DInProcessCommandBufferImpl::ClearContext() {
   // NOTE: Comment in the line below to check for code that is not calling
   // eglMakeCurrent where appropriate. The issue is code using
   // WebGraphicsContext3D does not need to call makeContextCurrent. Code using
   // direct OpenGL bindings needs to call the appropriate form of
   // eglMakeCurrent. If it doesn't it will be issuing commands on the wrong
   // context. Uncommenting the line below clears the current context so that
@@ skipping 1024 matching lines @@
 DELEGATE_TO_GL_1(genMailboxCHROMIUM, GenMailboxCHROMIUM, WGC3Dbyte*)
 DELEGATE_TO_GL_2(produceTextureCHROMIUM, ProduceTextureCHROMIUM,
                  WGC3Denum, const WGC3Dbyte*)
 DELEGATE_TO_GL_2(consumeTextureCHROMIUM, ConsumeTextureCHROMIUM,
                  WGC3Denum, const WGC3Dbyte*)
 
 DELEGATE_TO_GL_2(drawBuffersEXT, DrawBuffersEXT,
                  WGC3Dsizei, const WGC3Denum*)
 }  // namespace gpu
 }  // namespace webkit