Initial commit of the blimp/ folder and target

blimp/client/compositor/blimp_context_provider.cc

Index: blimp/client/compositor/blimp_context_provider.cc
diff --git a/blimp/client/compositor/blimp_context_provider.cc b/blimp/client/compositor/blimp_context_provider.cc
new file mode 100644
index 0000000000000000000000000000000000000000..57c46a74ef2f83d11a97572b73c4f770c3e993d1
--- /dev/null
+++ b/blimp/client/compositor/blimp_context_provider.cc
@@ -0,0 +1,188 @@
+// Copyright 2015 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 "blimp/client/compositor/blimp_context_provider.h"
+
+#include "base/bind.h"
+#include "base/callback_helpers.h"
+#include "base/lazy_instance.h"
+#include "gpu/command_buffer/client/gl_in_process_context.h"
+#include "gpu/command_buffer/client/gles2_implementation.h"
+#include "gpu/command_buffer/client/gles2_lib.h"
+#include "gpu/skia_bindings/gl_bindings_skia_cmd_buffer.h"
+#include "third_party/skia/include/gpu/GrContext.h"
+#include "third_party/skia/include/gpu/gl/GrGLInterface.h"
+
+namespace {
+
+// Singleton used to initialize and terminate the gles2 library.
+class GLES2Initializer {
+ public:
+  GLES2Initializer() { gles2::Initialize(); }
+
+  ~GLES2Initializer() { gles2::Terminate(); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(GLES2Initializer);
+};
+
+base::LazyInstance<GLES2Initializer> g_gles2_initializer =
+    LAZY_INSTANCE_INITIALIZER;
+
+static void BindGrContextCallback(const GrGLInterface* interface) {
+  blimp::BlimpContextProvider* context_provider =
+      reinterpret_cast<blimp::BlimpContextProvider*>(interface->fCallbackData);
+
+  gles2::SetGLContext(context_provider->ContextGL());
+}
+
+}  // namespace
+
+namespace blimp {
+
+// static
+scoped_refptr<BlimpContextProvider> BlimpContextProvider::Create(
+    gfx::AcceleratedWidget widget) {
+  return new BlimpContextProvider(widget);
+}
+
+BlimpContextProvider::BlimpContextProvider(gfx::AcceleratedWidget widget) {
+  context_thread_checker_.DetachFromThread();
+
+  gpu::gles2::ContextCreationAttribHelper attribs_for_gles2;
+  attribs_for_gles2.alpha_size = 8;
+  attribs_for_gles2.depth_size = 0;
+  attribs_for_gles2.stencil_size = 0;
+  attribs_for_gles2.samples = 0;
+  attribs_for_gles2.sample_buffers = 0;
+  attribs_for_gles2.fail_if_major_perf_caveat = false;
+  attribs_for_gles2.bind_generates_resource = false;
+  attribs_for_gles2.webgl_version = 0;
+  attribs_for_gles2.lose_context_when_out_of_memory = true;
+
+  context_.reset(gpu::GLInProcessContext::Create(
+      nullptr /* service */, nullptr /* surface */, false /* is_offscreen */,
+      widget, gfx::Size(1, 1), nullptr /* share_context */,
+      false /* share_resources */, attribs_for_gles2, gfx::PreferDiscreteGpu,
+      gpu::GLInProcessContextSharedMemoryLimits(),
+      nullptr /* gpu_memory_buffer_manager */, nullptr /* memory_limits */));
+  context_->SetContextLostCallback(
+      base::Bind(&BlimpContextProvider::OnLostContext, base::Unretained(this)));
+  CHECK(context_);

[danakj, 2015/08/28 17:38:46]

What's the point of this? You just crashed on the line above if context_ is
null. (And why CHECK not DCHECK.)

[David Trainor- moved to gerrit, 2015/08/28 18:24:16]

Gah I put it in the wrong place, I meant to put it before the dereference.  Also
I just re-read the style guide on this and it should be a DCHECK.

[Wez, 2015/08/31 16:27:18]

Actually, if you're about to deref the variable, and therefor crash in a
predictable way anyway, then you shouldn't put a [D]CHECK before it at all.

[David Trainor- moved to gerrit, 2015/08/31 21:25:43]

Yeah that's true.  I can make that change here because this is an interface, but
in general I'm a little wary of doing that because if the method doesn't access
the vtable/any member variables it won't necessarily crash (undefined behavior).
 If it calls a method on a member that also doesn't access it's vtable it gets
even more interesting.

[David Trainor- moved to gerrit, 2015/08/31 21:27:28]

scoped_ptr does have an assert, but it looks like that just becomes LOG_ASSERT
which doesn't actually stop execution if it fails on debug builds?  Either that
or I'm misreading it :(.

+}
+
+BlimpContextProvider::~BlimpContextProvider() {
+  DCHECK(main_thread_checker_.CalledOnValidThread() ||
+         context_thread_checker_.CalledOnValidThread());
+}
+
+bool BlimpContextProvider::BindToCurrentThread() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+  capabilities_.gpu = context_->GetImplementation()->capabilities();
+  capabilities_.gpu.image = true;
+  return true;
+}
+
+void BlimpContextProvider::DetachFromThread() {
+  context_thread_checker_.DetachFromThread();
+}
+
+cc::ContextProvider::Capabilities BlimpContextProvider::ContextCapabilities() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+  return capabilities_;
+}
+
+gpu::gles2::GLES2Interface* BlimpContextProvider::ContextGL() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+  return context_->GetImplementation();
+}
+
+gpu::ContextSupport* BlimpContextProvider::ContextSupport() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+  return context_->GetImplementation();
+}
+
+class GrContext* BlimpContextProvider::GrContext() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+
+  if (gr_context_)
+    return gr_context_.get();
+
+  // The GrGLInterface factory will make GL calls using the C GLES2 interface.
+  // Make sure the gles2 library is initialized first on exactly one thread.
+  g_gles2_initializer.Get();
+  gles2::SetGLContext(ContextGL());
+
+  skia::RefPtr<GrGLInterface> interface =
+      skia::AdoptRef(skia_bindings::CreateCommandBufferSkiaGLBinding());
+  interface->fCallback = BindGrContextCallback;
+  interface->fCallbackData = reinterpret_cast<GrGLInterfaceCallbackData>(this);
+
+  gr_context_ = skia::AdoptRef(GrContext::Create(
+      kOpenGL_GrBackend, reinterpret_cast<GrBackendContext>(interface.get())));
+
+  return gr_context_.get();
+}
+
+void BlimpContextProvider::InvalidateGrContext(uint32_t state) {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+
+  if (gr_context_)
+    gr_context_.get()->resetContext(state);
+}
+
+void BlimpContextProvider::SetupLock() {
+  context_->SetLock(&context_lock_);
+}
+
+base::Lock* BlimpContextProvider::GetLock() {
+  return &context_lock_;
+}
+
+void BlimpContextProvider::VerifyContexts() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+}
+
+void BlimpContextProvider::DeleteCachedResources() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+
+  if (gr_context_)
+    gr_context_->freeGpuResources();
+}
+
+bool BlimpContextProvider::DestroyedOnMainThread() {
+  DCHECK(main_thread_checker_.CalledOnValidThread());
+
+  base::AutoLock lock(destroyed_lock_);
+  return destroyed_;
+}
+
+void BlimpContextProvider::SetLostContextCallback(
+    const LostContextCallback& lost_context_callback) {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+  lost_context_callback_ = lost_context_callback;
+}
+
+void BlimpContextProvider::SetMemoryPolicyChangedCallback(
+    const MemoryPolicyChangedCallback& memory_policy_changed_callback) {
+  // There's no memory manager for the in-process implementation.
+}
+
+void BlimpContextProvider::OnLostContext() {
+  DCHECK(context_thread_checker_.CalledOnValidThread());
+
+  {
+    base::AutoLock lock(destroyed_lock_);
+    if (destroyed_)
+      return;
+    destroyed_ = true;
+  }
+
+  if (!lost_context_callback_.is_null())
+    base::ResetAndReturn(&lost_context_callback_).Run();
+  if (gr_context_)
+    gr_context_->abandonContext();
+}
+
+}  // namespace blimp