blob: 0f7610c8a3c027a2b403984e1076f0d22a4cba68 [file] [log] [blame]
// 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 "ui/gl/gl_fence.h"
#include "base/compiler_specific.h"
#include "ui/gl/gl_bindings.h"
#include "ui/gl/gl_context.h"
namespace {
class GLFenceNVFence: public gfx::GLFence {
public:
GLFenceNVFence() {
// What if either of these GL calls fails? TestFenceNV will return true.
// See spec:
// http://www.opengl.org/registry/specs/NV/fence.txt
//
// What should happen if TestFenceNV is called for a name before SetFenceNV
// is called?
// We generate an INVALID_OPERATION error, and return TRUE.
// This follows the semantics for texture object names before
// they are bound, in that they acquire their state upon binding.
// We will arbitrarily return TRUE for consistency.
glGenFencesNV(1, &fence_);
glSetFenceNV(fence_, GL_ALL_COMPLETED_NV);
glFlush();
}
virtual bool HasCompleted() OVERRIDE {
return IsContextLost() || glTestFenceNV(fence_);
}
private:
~GLFenceNVFence() {
glDeleteFencesNV(1, &fence_);
}
GLuint fence_;
};
class GLFenceARBSync: public gfx::GLFence {
public:
GLFenceARBSync() {
sync_ = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
glFlush();
}
virtual bool HasCompleted() OVERRIDE {
// Handle the case where FenceSync failed.
if (!sync_ || IsContextLost())
return true;
GLsizei length = 0;
GLsizei value = 0;
glGetSynciv(sync_,
GL_SYNC_STATUS,
1, // bufSize
&length,
&value);
return length == 1 && value == GL_SIGNALED;
}
private:
~GLFenceARBSync() {
glDeleteSync(sync_);
}
GLsync sync_;
};
} // namespace
namespace gfx {
GLFence::GLFence() {
}
GLFence::~GLFence() {
}
// static
GLFence* GLFence::Create() {
if (gfx::g_GL_NV_fence) {
return new GLFenceNVFence();
} else if (gfx::g_GL_ARB_sync) {
return new GLFenceARBSync();
} else {
return NULL;
}
}
// static
bool GLFence::IsContextLost() {
if (!gfx::g_GL_ARB_robustness && !gfx::g_GL_EXT_robustness)
return false;
if (!gfx::GLContext::GetCurrent() ||
!gfx::GLContext::GetCurrent()->
WasAllocatedUsingRobustnessExtension())
return false;
GLenum status = glGetGraphicsResetStatusARB();
return status != GL_NO_ERROR;
}
} // namespace gfx