Lazy initialize WGC3DInProcessCommandBufferImpl

webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc

Index: webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
diff --git a/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc b/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
index f55d5a3a759f2ee502c827b44c925830702541cf..032cc412074f93235ee1fde19b2fb207cff25a47 100644
--- a/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
+++ b/webkit/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
@@ -98,7 +98,6 @@ class GLInProcessContext : public base::SupportsWeakPtr<GLInProcessContext> {
   // outlive its parent.  attrib_list must be NULL or a NONE-terminated list of
   // attribute/value pairs.
   static GLInProcessContext* CreateOffscreenContext(
-      GLInProcessContext* parent,
       const gfx::Size& size,
       GLInProcessContext* context_group,
       const char* allowed_extensions,
@@ -145,7 +144,7 @@ class GLInProcessContext : public base::SupportsWeakPtr<GLInProcessContext> {
   CommandBufferService* GetCommandBufferService();
 
  private:
-  explicit GLInProcessContext(GLInProcessContext* parent);
+  GLInProcessContext();
 
   bool Initialize(const gfx::Size& size,
                   GLInProcessContext* context_group,
@@ -156,9 +155,7 @@ class GLInProcessContext : public base::SupportsWeakPtr<GLInProcessContext> {
 
   void OnContextLost();
 
-  base::WeakPtr<GLInProcessContext> parent_;
   base::Closure context_lost_callback_;
-  uint32 parent_texture_id_;
   scoped_ptr<TransferBufferManagerInterface> transfer_buffer_manager_;
   scoped_ptr<CommandBufferService> command_buffer_;
   scoped_ptr< ::gpu::GpuScheduler> gpu_scheduler_;
@@ -216,13 +213,12 @@ GLInProcessContext::~GLInProcessContext() {
 }
 
 GLInProcessContext* GLInProcessContext::CreateOffscreenContext(
-    GLInProcessContext* parent,
     const gfx::Size& size,
     GLInProcessContext* context_group,
     const char* allowed_extensions,
     const int32* attrib_list,
     gfx::GpuPreference gpu_preference) {
-  scoped_ptr<GLInProcessContext> context(new GLInProcessContext(parent));
+  scoped_ptr<GLInProcessContext> context(new GLInProcessContext);
   if (!context->Initialize(
       size,
       context_group,
@@ -259,7 +255,7 @@ bool GLInProcessContext::GetBufferChanged(int32 transfer_buffer_id) {
 }
 
 uint32 GLInProcessContext::GetParentTextureId() {
-  return parent_texture_id_;
+  return NULL;
 }
 
 uint32 GLInProcessContext::CreateParentTexture(const gfx::Size& size) {
@@ -341,11 +337,8 @@ GLES2Implementation* GLInProcessContext::GetImplementation() {
   return gles2_implementation_.get();
 }
 
-GLInProcessContext::GLInProcessContext(GLInProcessContext* parent)
-    : parent_(parent ?
-          parent->AsWeakPtr() : base::WeakPtr<GLInProcessContext>()),
-      parent_texture_id_(0),
-      last_error_(SUCCESS),
+GLInProcessContext::GLInProcessContext()
+    : last_error_(SUCCESS),
       context_lost_(false) {
 }
 
@@ -363,15 +356,6 @@ bool GLInProcessContext::Initialize(const gfx::Size& size,
   // Ensure the gles2 library is initialized first in a thread safe way.
   g_gles2_initializer.Get();
 
-  // Allocate a frame buffer ID with respect to the parent.
-  if (parent_.get()) {
-    // Flush any remaining commands in the parent context to make sure the
-    // texture id accounting stays consistent.
-    int32 token = parent_->gles2_helper_->InsertToken();
-    parent_->gles2_helper_->WaitForToken(token);
-    parent_texture_id_ = parent_->gles2_implementation_->MakeTextureId();
-  }
-
   std::vector<int32> attribs;
   while (attrib_list) {
     int32 attrib = *attrib_list++;
@@ -465,14 +449,6 @@ bool GLInProcessContext::Initialize(const gfx::Size& size,
     return false;
   }
 
-  if (!decoder_->SetParent(
-      parent_.get() ? parent_->decoder_.get() : NULL,
-      parent_texture_id_)) {
-    LOG(ERROR) << "Could not set parent.";
-    Destroy();
-    return false;
-  }
-
   command_buffer_->SetPutOffsetChangeCallback(
       base::Bind(&GLInProcessContext::PumpCommands, base::Unretained(this)));
   command_buffer_->SetGetBufferChangeCallback(
@@ -512,11 +488,6 @@ bool GLInProcessContext::Initialize(const gfx::Size& size,
 void GLInProcessContext::Destroy() {
   bool context_lost = IsCommandBufferContextLost();
 
-  if (parent_.get() && parent_texture_id_ != 0) {
-    parent_->gles2_implementation_->FreeTextureId(parent_texture_id_);
-    parent_texture_id_ = 0;
-  }
-
   if (gles2_implementation_.get()) {
     // First flush the context to ensure that any pending frees of resources
     // are completed. Otherwise, if this context is part of a share group,
@@ -543,11 +514,15 @@ void GLInProcessContext::OnContextLost() {
 }
 
 WebGraphicsContext3DInProcessCommandBufferImpl::
-    WebGraphicsContext3DInProcessCommandBufferImpl()
-    : context_(NULL),
+    WebGraphicsContext3DInProcessCommandBufferImpl(
+        const WebKit::WebGraphicsContext3D::Attributes& attributes)
+    : initialized_(false),
+      initialize_failed_(false),
+      context_(NULL),
       gl_(NULL),
       context_lost_callback_(NULL),
       context_lost_reason_(GL_NO_ERROR),
+      attributes_(attributes),
       cached_width_(0),
       cached_height_(0),
       bound_fbo_(0) {
@@ -559,16 +534,20 @@ WebGraphicsContext3DInProcessCommandBufferImpl::
   g_all_shared_contexts.Pointer()->erase(this);
 }
 
-bool WebGraphicsContext3DInProcessCommandBufferImpl::Initialize(
-    WebGraphicsContext3D::Attributes attributes,
-    WebKit::WebGraphicsContext3D* view_context) {
+bool WebGraphicsContext3DInProcessCommandBufferImpl::MaybeInitializeGL() {
+  if (initialized_)
+    return true;
+
+  if (initialize_failed_)
+    return false;
+
   // 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,
@@ -587,34 +566,27 @@ bool WebGraphicsContext3DInProcessCommandBufferImpl::Initialize(
   // 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,
       gfx::Size(1, 1),
       context_group ? context_group->context_ : NULL,
       preferred_extensions,
       attribs,
       gpu_preference);
 
-  if (!context_)
+  if (!context_) {
+    initialize_failed_ = true;
     return false;
+  }
 
   gl_ = context_->GetImplementation();
 
-  if (gl_ && attributes.noExtensions)
+  if (gl_ && attributes_.noExtensions)
     gl_->EnableFeatureCHROMIUM("webgl_enable_glsl_webgl_validation");
 
   context_->SetContextLostCallback(
@@ -624,7 +596,6 @@ bool WebGraphicsContext3DInProcessCommandBufferImpl::Initialize(
 
   // Set attributes_ from created offscreen context.
   {
-    attributes_ = attributes;
     GLint alpha_bits = 0;
     getIntegerv(GL_ALPHA_BITS, &alpha_bits);
     attributes_.alpha = alpha_bits > 0;
@@ -638,15 +609,18 @@ bool WebGraphicsContext3DInProcessCommandBufferImpl::Initialize(
     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);
 
+  initialized_ = false;

[jamesr, 2013/03/21 23:19:18]

did you mean "initialized_ = true;" ?

   return true;
 }
 
 bool WebGraphicsContext3DInProcessCommandBufferImpl::makeContextCurrent() {
+  if (!MaybeInitializeGL())
+    return false;
+
   return GLInProcessContext::MakeCurrent(context_);
 }