gpu/command_buffer/service/texture_definition.cc - chromium/src - Git at Google

 // Copyright 2014 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 "gpu/command_buffer/service/texture_definition.h"

 #include <stdint.h>

 #include <list>

 #include "base/lazy_instance.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_local.h"
 // gl_stream_texture_image.h is included to work around crbug.com/595189, a
 // compiler bug in VS 2015 Update 2 RC.
 #include "gpu/command_buffer/service/gl_stream_texture_image.h"
 #include "gpu/command_buffer/service/texture_manager.h"
 #include "ui/gl/gl_image.h"
 #include "ui/gl/gl_implementation.h"
 #include "ui/gl/scoped_binders.h"

 #if !defined(OS_MACOSX)
 #include "base/macros.h"
 #include "ui/gl/gl_surface_egl.h"
 #endif

 namespace gpu {
 namespace gles2 {

 namespace {

 class GLImageSync : public gl::GLImage {
  public:
   explicit GLImageSync(const scoped_refptr<NativeImageBuffer>& buffer,
                        const gfx::Size& size);

   // Implement GLImage.
   void Destroy(bool have_context) override;
   gfx::Size GetSize() override;
   unsigned GetInternalFormat() override;
   bool BindTexImage(unsigned target) override;
   void ReleaseTexImage(unsigned target) override;
   bool CopyTexImage(unsigned target) override;
   bool CopyTexSubImage(unsigned target,
                        const gfx::Point& offset,
                        const gfx::Rect& rect) override;
   bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                             int z_order,
                             gfx::OverlayTransform transform,
                             const gfx::Rect& bounds_rect,
                             const gfx::RectF& crop_rect) override;
   void Flush() override {}
   void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                     uint64_t process_tracing_id,
                     const std::string& dump_name) override;

  protected:
   ~GLImageSync() override;

  private:
   scoped_refptr<NativeImageBuffer> buffer_;
   gfx::Size size_;

   DISALLOW_COPY_AND_ASSIGN(GLImageSync);
 };

 GLImageSync::GLImageSync(const scoped_refptr<NativeImageBuffer>& buffer,
                          const gfx::Size& size)
     : buffer_(buffer), size_(size) {
   if (buffer.get())
     buffer->AddClient(this);
 }

 GLImageSync::~GLImageSync() {
   if (buffer_.get())
     buffer_->RemoveClient(this);
 }

 void GLImageSync::Destroy(bool have_context) {
 }

 gfx::Size GLImageSync::GetSize() {
   return size_;
 }

 unsigned GLImageSync::GetInternalFormat() {
   return GL_RGBA;
 }

 bool GLImageSync::BindTexImage(unsigned target) {
   NOTREACHED();
   return false;
 }

 void GLImageSync::ReleaseTexImage(unsigned target) {
   NOTREACHED();
 }

 bool GLImageSync::CopyTexImage(unsigned target) {
   return false;
 }

 bool GLImageSync::CopyTexSubImage(unsigned target,
                                   const gfx::Point& offset,
                                   const gfx::Rect& rect) {
   return false;
 }

 bool GLImageSync::ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
                                        int z_order,
                                        gfx::OverlayTransform transform,
                                        const gfx::Rect& bounds_rect,
                                        const gfx::RectF& crop_rect) {
   NOTREACHED();
   return false;
 }

 void GLImageSync::OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                                uint64_t process_tracing_id,
                                const std::string& dump_name) {
   // TODO(ericrk): Implement GLImage OnMemoryDump. crbug.com/514914
 }

 #if !defined(OS_MACOSX)
 class NativeImageBufferEGL : public NativeImageBuffer {
  public:
   static scoped_refptr<NativeImageBufferEGL> Create(GLuint texture_id);

  private:
   NativeImageBufferEGL(EGLDisplay display, EGLImageKHR image);
   ~NativeImageBufferEGL() override;
   void AddClient(gl::GLImage* client) override;
   void RemoveClient(gl::GLImage* client) override;
   bool IsClient(gl::GLImage* client) override;
   void BindToTexture(GLenum target) const override;

   const EGLDisplay egl_display_;
   const EGLImageKHR egl_image_;

   base::Lock lock_;

   struct ClientInfo {
     explicit ClientInfo(gl::GLImage* client);
     ~ClientInfo();

     gl::GLImage* client;
     bool needs_wait_before_read;
   };
   std::list<ClientInfo> client_infos_;
   gl::GLImage* write_client_;

   DISALLOW_COPY_AND_ASSIGN(NativeImageBufferEGL);
 };

 scoped_refptr<NativeImageBufferEGL> NativeImageBufferEGL::Create(
     GLuint texture_id) {
   EGLDisplay egl_display = gl::GLSurfaceEGL::GetHardwareDisplay();
   EGLContext egl_context = eglGetCurrentContext();

   DCHECK_NE(EGL_NO_CONTEXT, egl_context);
   DCHECK_NE(EGL_NO_DISPLAY, egl_display);
   DCHECK(glIsTexture(texture_id));

   DCHECK(gl::g_driver_egl.ext.b_EGL_KHR_image_base &&
          gl::g_driver_egl.ext.b_EGL_KHR_gl_texture_2D_image &&
          gl::g_driver_gl.ext.b_GL_OES_EGL_image);

   const EGLint egl_attrib_list[] = {
       EGL_GL_TEXTURE_LEVEL_KHR, 0, EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE};
   EGLClientBuffer egl_buffer = reinterpret_cast<EGLClientBuffer>(texture_id);
   EGLenum egl_target = EGL_GL_TEXTURE_2D_KHR;

   EGLImageKHR egl_image = eglCreateImageKHR(
       egl_display, egl_context, egl_target, egl_buffer, egl_attrib_list);

   if (egl_image == EGL_NO_IMAGE_KHR) {
     LOG(ERROR) << "eglCreateImageKHR for cross-thread sharing failed: 0x"
                << std::hex << eglGetError();
     return NULL;
   }

   return new NativeImageBufferEGL(egl_display, egl_image);
 }

 NativeImageBufferEGL::ClientInfo::ClientInfo(gl::GLImage* client)
     : client(client), needs_wait_before_read(true) {}

 NativeImageBufferEGL::ClientInfo::~ClientInfo() {}

 NativeImageBufferEGL::NativeImageBufferEGL(EGLDisplay display,
                                            EGLImageKHR image)
     : NativeImageBuffer(),
       egl_display_(display),
       egl_image_(image),
       write_client_(NULL) {
   DCHECK(egl_display_ != EGL_NO_DISPLAY);
   DCHECK(egl_image_ != EGL_NO_IMAGE_KHR);
 }

 NativeImageBufferEGL::~NativeImageBufferEGL() {
   DCHECK(client_infos_.empty());
   if (egl_image_ != EGL_NO_IMAGE_KHR)
     eglDestroyImageKHR(egl_display_, egl_image_);
 }

 void NativeImageBufferEGL::AddClient(gl::GLImage* client) {
   base::AutoLock lock(lock_);
   client_infos_.push_back(ClientInfo(client));
 }

 void NativeImageBufferEGL::RemoveClient(gl::GLImage* client) {
   base::AutoLock lock(lock_);
   if (write_client_ == client)
     write_client_ = NULL;
   for (std::list<ClientInfo>::iterator it = client_infos_.begin();
        it != client_infos_.end();
        it++) {
     if (it->client == client) {
       client_infos_.erase(it);
       return;
     }
   }
   NOTREACHED();
 }

 bool NativeImageBufferEGL::IsClient(gl::GLImage* client) {
   base::AutoLock lock(lock_);
   for (std::list<ClientInfo>::iterator it = client_infos_.begin();
        it != client_infos_.end();
        it++) {
     if (it->client == client)
       return true;
   }
   return false;
 }

 void NativeImageBufferEGL::BindToTexture(GLenum target) const {
   DCHECK(egl_image_ != EGL_NO_IMAGE_KHR);
   glEGLImageTargetTexture2DOES(target, egl_image_);
   DCHECK_EQ(static_cast<EGLint>(EGL_SUCCESS), eglGetError());
   DCHECK_EQ(static_cast<GLenum>(GL_NO_ERROR), glGetError());
 }

 #endif

 class NativeImageBufferStub : public NativeImageBuffer {
  public:
   NativeImageBufferStub() : NativeImageBuffer() {}

  private:
   ~NativeImageBufferStub() override {}
   void AddClient(gl::GLImage* client) override {}
   void RemoveClient(gl::GLImage* client) override {}
   bool IsClient(gl::GLImage* client) override { return true; }
   void BindToTexture(GLenum target) const override {}

   DISALLOW_COPY_AND_ASSIGN(NativeImageBufferStub);
 };

 bool g_avoid_egl_target_texture_reuse = false;

 }  // anonymous namespace

 // static
 scoped_refptr<NativeImageBuffer> NativeImageBuffer::Create(GLuint texture_id) {
   switch (gl::GetGLImplementation()) {
 #if !defined(OS_MACOSX)
     case gl::kGLImplementationEGLGLES2:
       return NativeImageBufferEGL::Create(texture_id);
 #endif
     case gl::kGLImplementationMockGL:
       return new NativeImageBufferStub;
     default:
       NOTREACHED();
       return NULL;
   }
 }

 // static
 void TextureDefinition::AvoidEGLTargetTextureReuse() {
   g_avoid_egl_target_texture_reuse = true;
 }

 TextureDefinition::LevelInfo::LevelInfo()
     : target(0),
       internal_format(0),
       width(0),
       height(0),
       depth(0),
       border(0),
       format(0),
       type(0) {
 }

 TextureDefinition::LevelInfo::LevelInfo(GLenum target,
                                         GLenum internal_format,
                                         GLsizei width,
                                         GLsizei height,
                                         GLsizei depth,
                                         GLint border,
                                         GLenum format,
                                         GLenum type,
                                         const gfx::Rect& cleared_rect)
     : target(target),
       internal_format(internal_format),
       width(width),
       height(height),
       depth(depth),
       border(border),
       format(format),
       type(type),
       cleared_rect(cleared_rect) {
 }

 TextureDefinition::LevelInfo::LevelInfo(const LevelInfo& other) = default;

 TextureDefinition::LevelInfo::~LevelInfo() {}

 TextureDefinition::TextureDefinition()
     : version_(0),
       target_(0),
       min_filter_(0),
       mag_filter_(0),
       wrap_s_(0),
       wrap_t_(0),
       usage_(0),
       immutable_(true) {
 }

 TextureDefinition::TextureDefinition(
     Texture* texture,
     unsigned int version,
     const scoped_refptr<NativeImageBuffer>& image_buffer)
     : version_(version),
       target_(texture->target()),
       image_buffer_(image_buffer),
       min_filter_(texture->min_filter()),
       mag_filter_(texture->mag_filter()),
       wrap_s_(texture->wrap_s()),
       wrap_t_(texture->wrap_t()),
       usage_(texture->usage()),
       immutable_(texture->IsImmutable()),
       defined_(texture->IsDefined()) {
   DCHECK(!image_buffer_.get() || defined_);
   if (!image_buffer_.get() && defined_) {
     image_buffer_ = NativeImageBuffer::Create(texture->service_id());
     DCHECK(image_buffer_.get());
   }

   const Texture::FaceInfo& first_face = texture->face_infos_[0];
   if (image_buffer_.get()) {
     scoped_refptr<gl::GLImage> gl_image(new GLImageSync(
         image_buffer_, gfx::Size(first_face.level_infos[0].width,
                                  first_face.level_infos[0].height)));
     texture->SetLevelImage(target_, 0, gl_image.get(), Texture::BOUND);
   }

   const Texture::LevelInfo& level = first_face.level_infos[0];
   level_info_ = LevelInfo(level.target, level.internal_format, level.width,
                           level.height, level.depth, level.border, level.format,
                           level.type, level.cleared_rect);
 }

 TextureDefinition::TextureDefinition(const TextureDefinition& other) = default;

 TextureDefinition::~TextureDefinition() {
 }

 Texture* TextureDefinition::CreateTexture() const {
   GLuint texture_id;
   glGenTextures(1, &texture_id);

   Texture* texture(new Texture(texture_id));
   UpdateTextureInternal(texture);

   return texture;
 }

 void TextureDefinition::UpdateTextureInternal(Texture* texture) const {
   gl::ScopedTextureBinder texture_binder(target_, texture->service_id());
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter_);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, mag_filter_);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrap_s_);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrap_t_);

   if (image_buffer_.get()) {
     gl::GLImage* existing_image = texture->GetLevelImage(target_, 0);
     // Don't need to re-bind if already bound before.
     if (!existing_image || !image_buffer_->IsClient(existing_image)) {
       image_buffer_->BindToTexture(target_);
     }
   }

   if (defined_) {
     texture->face_infos_.resize(1);
     texture->face_infos_[0].level_infos.resize(1);
     texture->SetLevelInfo(level_info_.target, 0,
                           level_info_.internal_format, level_info_.width,
                           level_info_.height, level_info_.depth,
                           level_info_.border, level_info_.format,
                           level_info_.type, level_info_.cleared_rect);
     texture->face_infos_[0].level_infos.resize(
         texture->face_infos_[0].num_mip_levels);
   }

   if (image_buffer_.get()) {
     texture->SetLevelImage(
         target_, 0,
         new GLImageSync(image_buffer_,
                         gfx::Size(level_info_.width, level_info_.height)),
         Texture::BOUND);
   }

   texture->target_ = target_;
   texture->SetImmutable(immutable_);
   texture->sampler_state_.min_filter = min_filter_;
   texture->sampler_state_.mag_filter = mag_filter_;
   texture->sampler_state_.wrap_s = wrap_s_;
   texture->sampler_state_.wrap_t = wrap_t_;
   texture->usage_ = usage_;
 }

 void TextureDefinition::UpdateTexture(Texture* texture) const {
   GLuint old_service_id = 0u;
   if (image_buffer_.get() && g_avoid_egl_target_texture_reuse) {
     GLuint service_id = 0u;
     glGenTextures(1, &service_id);
     old_service_id = texture->service_id();
     texture->SetServiceId(service_id);

     DCHECK_EQ(static_cast<GLenum>(GL_TEXTURE_2D), target_);
     GLint bound_id = 0;
     glGetIntegerv(GL_TEXTURE_BINDING_2D, &bound_id);
     if (bound_id == static_cast<GLint>(old_service_id)) {
       glBindTexture(target_, service_id);
     }
     texture->SetLevelImage(target_, 0, NULL, Texture::UNBOUND);
   }

   UpdateTextureInternal(texture);

   if (old_service_id) {
     glDeleteTextures(1, &old_service_id);
   }
 }

 bool TextureDefinition::Matches(const Texture* texture) const {
   DCHECK(target_ == texture->target());
   if (texture->sampler_state_.min_filter != min_filter_ ||
       texture->sampler_state_.mag_filter != mag_filter_ ||
       texture->sampler_state_.wrap_s != wrap_s_ ||
       texture->sampler_state_.wrap_t != wrap_t_ ||
       texture->SafeToRenderFrom() != SafeToRenderFrom()) {
     return false;
   }

   // Texture became defined.
   if (!image_buffer_.get() && texture->IsDefined())
     return false;

   // All structural changes should have orphaned the texture.
   if (image_buffer_.get() && !texture->GetLevelImage(texture->target(), 0))
     return false;

   return true;
 }

 bool TextureDefinition::SafeToRenderFrom() const {
   return level_info_.cleared_rect.Contains(
       gfx::Rect(level_info_.width, level_info_.height));
 }

 }  // namespace gles2
 }  // namespace gpu
	// Copyright 2014 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 "gpu/command_buffer/service/texture_definition.h"

	#include <stdint.h>

	#include <list>

	#include "base/lazy_instance.h"
	#include "base/synchronization/lock.h"
	#include "base/threading/thread_local.h"
	// gl_stream_texture_image.h is included to work around crbug.com/595189, a
	// compiler bug in VS 2015 Update 2 RC.
	#include "gpu/command_buffer/service/gl_stream_texture_image.h"
	#include "gpu/command_buffer/service/texture_manager.h"
	#include "ui/gl/gl_image.h"
	#include "ui/gl/gl_implementation.h"
	#include "ui/gl/scoped_binders.h"

	#if !defined(OS_MACOSX)
	#include "base/macros.h"
	#include "ui/gl/gl_surface_egl.h"
	#endif

	namespace gpu {
	namespace gles2 {

	namespace {

	class GLImageSync : public gl::GLImage {
	public:
	explicit GLImageSync(const scoped_refptr<NativeImageBuffer>& buffer,
	const gfx::Size& size);

	// Implement GLImage.
	void Destroy(bool have_context) override;
	gfx::Size GetSize() override;
	unsigned GetInternalFormat() override;
	bool BindTexImage(unsigned target) override;
	void ReleaseTexImage(unsigned target) override;
	bool CopyTexImage(unsigned target) override;
	bool CopyTexSubImage(unsigned target,
	const gfx::Point& offset,
	const gfx::Rect& rect) override;
	bool ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
	int z_order,
	gfx::OverlayTransform transform,
	const gfx::Rect& bounds_rect,
	const gfx::RectF& crop_rect) override;
	void Flush() override {}
	void OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
	uint64_t process_tracing_id,
	const std::string& dump_name) override;

	protected:
	~GLImageSync() override;

	private:
	scoped_refptr<NativeImageBuffer> buffer_;
	gfx::Size size_;

	DISALLOW_COPY_AND_ASSIGN(GLImageSync);
	};

	GLImageSync::GLImageSync(const scoped_refptr<NativeImageBuffer>& buffer,
	const gfx::Size& size)
	: buffer_(buffer), size_(size) {
	if (buffer.get())
	buffer->AddClient(this);
	}

	GLImageSync::~GLImageSync() {
	if (buffer_.get())
	buffer_->RemoveClient(this);
	}

	void GLImageSync::Destroy(bool have_context) {
	}

	gfx::Size GLImageSync::GetSize() {
	return size_;
	}

	unsigned GLImageSync::GetInternalFormat() {
	return GL_RGBA;
	}

	bool GLImageSync::BindTexImage(unsigned target) {
	NOTREACHED();
	return false;
	}

	void GLImageSync::ReleaseTexImage(unsigned target) {
	NOTREACHED();
	}

	bool GLImageSync::CopyTexImage(unsigned target) {
	return false;
	}

	bool GLImageSync::CopyTexSubImage(unsigned target,
	const gfx::Point& offset,
	const gfx::Rect& rect) {
	return false;
	}

	bool GLImageSync::ScheduleOverlayPlane(gfx::AcceleratedWidget widget,
	int z_order,
	gfx::OverlayTransform transform,
	const gfx::Rect& bounds_rect,
	const gfx::RectF& crop_rect) {
	NOTREACHED();
	return false;
	}

	void GLImageSync::OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
	uint64_t process_tracing_id,
	const std::string& dump_name) {
	// TODO(ericrk): Implement GLImage OnMemoryDump. crbug.com/514914
	}

	#if !defined(OS_MACOSX)
	class NativeImageBufferEGL : public NativeImageBuffer {
	public:
	static scoped_refptr<NativeImageBufferEGL> Create(GLuint texture_id);

	private:
	NativeImageBufferEGL(EGLDisplay display, EGLImageKHR image);
	~NativeImageBufferEGL() override;
	void AddClient(gl::GLImage* client) override;
	void RemoveClient(gl::GLImage* client) override;
	bool IsClient(gl::GLImage* client) override;
	void BindToTexture(GLenum target) const override;

	const EGLDisplay egl_display_;
	const EGLImageKHR egl_image_;

	base::Lock lock_;

	struct ClientInfo {
	explicit ClientInfo(gl::GLImage* client);
	~ClientInfo();

	gl::GLImage* client;
	bool needs_wait_before_read;
	};
	std::list<ClientInfo> client_infos_;
	gl::GLImage* write_client_;

	DISALLOW_COPY_AND_ASSIGN(NativeImageBufferEGL);
	};

	scoped_refptr<NativeImageBufferEGL> NativeImageBufferEGL::Create(
	GLuint texture_id) {
	EGLDisplay egl_display = gl::GLSurfaceEGL::GetHardwareDisplay();
	EGLContext egl_context = eglGetCurrentContext();

	DCHECK_NE(EGL_NO_CONTEXT, egl_context);
	DCHECK_NE(EGL_NO_DISPLAY, egl_display);
	DCHECK(glIsTexture(texture_id));

	DCHECK(gl::g_driver_egl.ext.b_EGL_KHR_image_base &&
	gl::g_driver_egl.ext.b_EGL_KHR_gl_texture_2D_image &&
	gl::g_driver_gl.ext.b_GL_OES_EGL_image);

	const EGLint egl_attrib_list[] = {
	EGL_GL_TEXTURE_LEVEL_KHR, 0, EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE};
	EGLClientBuffer egl_buffer = reinterpret_cast<EGLClientBuffer>(texture_id);
	EGLenum egl_target = EGL_GL_TEXTURE_2D_KHR;

	EGLImageKHR egl_image = eglCreateImageKHR(
	egl_display, egl_context, egl_target, egl_buffer, egl_attrib_list);

	if (egl_image == EGL_NO_IMAGE_KHR) {
	LOG(ERROR) << "eglCreateImageKHR for cross-thread sharing failed: 0x"
	<< std::hex << eglGetError();
	return NULL;
	}

	return new NativeImageBufferEGL(egl_display, egl_image);
	}

	NativeImageBufferEGL::ClientInfo::ClientInfo(gl::GLImage* client)
	: client(client), needs_wait_before_read(true) {}

	NativeImageBufferEGL::ClientInfo::~ClientInfo() {}

	NativeImageBufferEGL::NativeImageBufferEGL(EGLDisplay display,
	EGLImageKHR image)
	: NativeImageBuffer(),
	egl_display_(display),
	egl_image_(image),
	write_client_(NULL) {
	DCHECK(egl_display_ != EGL_NO_DISPLAY);
	DCHECK(egl_image_ != EGL_NO_IMAGE_KHR);
	}

	NativeImageBufferEGL::~NativeImageBufferEGL() {
	DCHECK(client_infos_.empty());
	if (egl_image_ != EGL_NO_IMAGE_KHR)
	eglDestroyImageKHR(egl_display_, egl_image_);
	}

	void NativeImageBufferEGL::AddClient(gl::GLImage* client) {
	base::AutoLock lock(lock_);
	client_infos_.push_back(ClientInfo(client));
	}

	void NativeImageBufferEGL::RemoveClient(gl::GLImage* client) {
	base::AutoLock lock(lock_);
	if (write_client_ == client)
	write_client_ = NULL;
	for (std::list<ClientInfo>::iterator it = client_infos_.begin();
	it != client_infos_.end();
	it++) {
	if (it->client == client) {
	client_infos_.erase(it);
	return;
	}
	}
	NOTREACHED();
	}

	bool NativeImageBufferEGL::IsClient(gl::GLImage* client) {
	base::AutoLock lock(lock_);
	for (std::list<ClientInfo>::iterator it = client_infos_.begin();
	it != client_infos_.end();
	it++) {
	if (it->client == client)
	return true;
	}
	return false;
	}

	void NativeImageBufferEGL::BindToTexture(GLenum target) const {
	DCHECK(egl_image_ != EGL_NO_IMAGE_KHR);
	glEGLImageTargetTexture2DOES(target, egl_image_);
	DCHECK_EQ(static_cast<EGLint>(EGL_SUCCESS), eglGetError());
	DCHECK_EQ(static_cast<GLenum>(GL_NO_ERROR), glGetError());
	}

	#endif

	class NativeImageBufferStub : public NativeImageBuffer {
	public:
	NativeImageBufferStub() : NativeImageBuffer() {}

	private:
	~NativeImageBufferStub() override {}
	void AddClient(gl::GLImage* client) override {}
	void RemoveClient(gl::GLImage* client) override {}
	bool IsClient(gl::GLImage* client) override { return true; }
	void BindToTexture(GLenum target) const override {}

	DISALLOW_COPY_AND_ASSIGN(NativeImageBufferStub);
	};

	bool g_avoid_egl_target_texture_reuse = false;

	} // anonymous namespace

	// static
	scoped_refptr<NativeImageBuffer> NativeImageBuffer::Create(GLuint texture_id) {
	switch (gl::GetGLImplementation()) {
	#if !defined(OS_MACOSX)
	case gl::kGLImplementationEGLGLES2:
	return NativeImageBufferEGL::Create(texture_id);
	#endif
	case gl::kGLImplementationMockGL:
	return new NativeImageBufferStub;
	default:
	NOTREACHED();
	return NULL;
	}
	}

	// static
	void TextureDefinition::AvoidEGLTargetTextureReuse() {
	g_avoid_egl_target_texture_reuse = true;
	}

	TextureDefinition::LevelInfo::LevelInfo()
	: target(0),
	internal_format(0),
	width(0),
	height(0),
	depth(0),
	border(0),
	format(0),
	type(0) {
	}

	TextureDefinition::LevelInfo::LevelInfo(GLenum target,
	GLenum internal_format,
	GLsizei width,
	GLsizei height,
	GLsizei depth,
	GLint border,
	GLenum format,
	GLenum type,
	const gfx::Rect& cleared_rect)
	: target(target),
	internal_format(internal_format),
	width(width),
	height(height),
	depth(depth),
	border(border),
	format(format),
	type(type),
	cleared_rect(cleared_rect) {
	}

	TextureDefinition::LevelInfo::LevelInfo(const LevelInfo& other) = default;

	TextureDefinition::LevelInfo::~LevelInfo() {}

	TextureDefinition::TextureDefinition()
	: version_(0),
	target_(0),
	min_filter_(0),
	mag_filter_(0),
	wrap_s_(0),
	wrap_t_(0),
	usage_(0),
	immutable_(true) {
	}

	TextureDefinition::TextureDefinition(
	Texture* texture,
	unsigned int version,
	const scoped_refptr<NativeImageBuffer>& image_buffer)
	: version_(version),
	target_(texture->target()),
	image_buffer_(image_buffer),
	min_filter_(texture->min_filter()),
	mag_filter_(texture->mag_filter()),
	wrap_s_(texture->wrap_s()),
	wrap_t_(texture->wrap_t()),
	usage_(texture->usage()),
	immutable_(texture->IsImmutable()),
	defined_(texture->IsDefined()) {
	DCHECK(!image_buffer_.get() \|\| defined_);
	if (!image_buffer_.get() && defined_) {
	image_buffer_ = NativeImageBuffer::Create(texture->service_id());
	DCHECK(image_buffer_.get());
	}

	const Texture::FaceInfo& first_face = texture->face_infos_[0];
	if (image_buffer_.get()) {
	scoped_refptr<gl::GLImage> gl_image(new GLImageSync(
	image_buffer_, gfx::Size(first_face.level_infos[0].width,
	first_face.level_infos[0].height)));
	texture->SetLevelImage(target_, 0, gl_image.get(), Texture::BOUND);
	}

	const Texture::LevelInfo& level = first_face.level_infos[0];
	level_info_ = LevelInfo(level.target, level.internal_format, level.width,
	level.height, level.depth, level.border, level.format,
	level.type, level.cleared_rect);
	}

	TextureDefinition::TextureDefinition(const TextureDefinition& other) = default;

	TextureDefinition::~TextureDefinition() {
	}

	Texture* TextureDefinition::CreateTexture() const {
	GLuint texture_id;
	glGenTextures(1, &texture_id);

	Texture* texture(new Texture(texture_id));
	UpdateTextureInternal(texture);

	return texture;
	}

	void TextureDefinition::UpdateTextureInternal(Texture* texture) const {
	gl::ScopedTextureBinder texture_binder(target_, texture->service_id());
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter_);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, mag_filter_);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrap_s_);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrap_t_);

	if (image_buffer_.get()) {
	gl::GLImage* existing_image = texture->GetLevelImage(target_, 0);
	// Don't need to re-bind if already bound before.
	if (!existing_image \|\| !image_buffer_->IsClient(existing_image)) {
	image_buffer_->BindToTexture(target_);
	}
	}

	if (defined_) {
	texture->face_infos_.resize(1);
	texture->face_infos_[0].level_infos.resize(1);
	texture->SetLevelInfo(level_info_.target, 0,
	level_info_.internal_format, level_info_.width,
	level_info_.height, level_info_.depth,
	level_info_.border, level_info_.format,
	level_info_.type, level_info_.cleared_rect);
	texture->face_infos_[0].level_infos.resize(
	texture->face_infos_[0].num_mip_levels);
	}

	if (image_buffer_.get()) {
	texture->SetLevelImage(
	target_, 0,
	new GLImageSync(image_buffer_,
	gfx::Size(level_info_.width, level_info_.height)),
	Texture::BOUND);
	}

	texture->target_ = target_;
	texture->SetImmutable(immutable_);
	texture->sampler_state_.min_filter = min_filter_;
	texture->sampler_state_.mag_filter = mag_filter_;
	texture->sampler_state_.wrap_s = wrap_s_;
	texture->sampler_state_.wrap_t = wrap_t_;
	texture->usage_ = usage_;
	}

	void TextureDefinition::UpdateTexture(Texture* texture) const {
	GLuint old_service_id = 0u;
	if (image_buffer_.get() && g_avoid_egl_target_texture_reuse) {
	GLuint service_id = 0u;
	glGenTextures(1, &service_id);
	old_service_id = texture->service_id();
	texture->SetServiceId(service_id);

	DCHECK_EQ(static_cast<GLenum>(GL_TEXTURE_2D), target_);
	GLint bound_id = 0;
	glGetIntegerv(GL_TEXTURE_BINDING_2D, &bound_id);
	if (bound_id == static_cast<GLint>(old_service_id)) {
	glBindTexture(target_, service_id);
	}
	texture->SetLevelImage(target_, 0, NULL, Texture::UNBOUND);
	}

	UpdateTextureInternal(texture);

	if (old_service_id) {
	glDeleteTextures(1, &old_service_id);
	}
	}

	bool TextureDefinition::Matches(const Texture* texture) const {
	DCHECK(target_ == texture->target());
	if (texture->sampler_state_.min_filter != min_filter_ \|\|
	texture->sampler_state_.mag_filter != mag_filter_ \|\|
	texture->sampler_state_.wrap_s != wrap_s_ \|\|
	texture->sampler_state_.wrap_t != wrap_t_ \|\|
	texture->SafeToRenderFrom() != SafeToRenderFrom()) {
	return false;
	}

	// Texture became defined.
	if (!image_buffer_.get() && texture->IsDefined())
	return false;

	// All structural changes should have orphaned the texture.
	if (image_buffer_.get() && !texture->GetLevelImage(texture->target(), 0))
	return false;

	return true;
	}

	bool TextureDefinition::SafeToRenderFrom() const {
	return level_info_.cleared_rect.Contains(
	gfx::Rect(level_info_.width, level_info_.height));
	}

	} // namespace gles2
	} // namespace gpu