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/*
* Copyright (C) 2009 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "core/html/canvas/WebGLFramebuffer.h"
#include "core/html/canvas/WebGLRenderingContext.h"
#include "platform/NotImplemented.h"
#include "platform/graphics/Extensions3D.h"
namespace WebCore {
namespace {
Platform3DObject objectOrZero(WebGLObject* object)
{
return object ? object->object() : 0;
}
class WebGLRenderbufferAttachment : public WebGLFramebuffer::WebGLAttachment {
public:
static PassRefPtr<WebGLFramebuffer::WebGLAttachment> create(WebGLRenderbuffer*);
private:
WebGLRenderbufferAttachment(WebGLRenderbuffer*);
virtual GC3Dsizei width() const;
virtual GC3Dsizei height() const;
virtual GC3Denum format() const;
virtual GC3Denum type() const;
virtual WebGLSharedObject* object() const;
virtual bool isSharedObject(WebGLSharedObject*) const;
virtual bool valid() const;
virtual bool initialized() const;
virtual void setInitialized();
virtual void onDetached(GraphicsContext3D*);
virtual void attach(GraphicsContext3D*, GC3Denum attachment);
virtual void unattach(GraphicsContext3D*, GC3Denum attachment);
WebGLRenderbufferAttachment() { };
RefPtr<WebGLRenderbuffer> m_renderbuffer;
};
PassRefPtr<WebGLFramebuffer::WebGLAttachment> WebGLRenderbufferAttachment::create(WebGLRenderbuffer* renderbuffer)
{
return adoptRef(new WebGLRenderbufferAttachment(renderbuffer));
}
WebGLRenderbufferAttachment::WebGLRenderbufferAttachment(WebGLRenderbuffer* renderbuffer)
: m_renderbuffer(renderbuffer)
{
}
GC3Dsizei WebGLRenderbufferAttachment::width() const
{
return m_renderbuffer->width();
}
GC3Dsizei WebGLRenderbufferAttachment::height() const
{
return m_renderbuffer->height();
}
GC3Denum WebGLRenderbufferAttachment::format() const
{
GC3Denum format = m_renderbuffer->internalFormat();
if (format == GraphicsContext3D::DEPTH_STENCIL
&& m_renderbuffer->emulatedStencilBuffer()
&& m_renderbuffer->emulatedStencilBuffer()->internalFormat() != GraphicsContext3D::STENCIL_INDEX8) {
return 0;
}
return format;
}
WebGLSharedObject* WebGLRenderbufferAttachment::object() const
{
return m_renderbuffer->object() ? m_renderbuffer.get() : 0;
}
bool WebGLRenderbufferAttachment::isSharedObject(WebGLSharedObject* object) const
{
return object == m_renderbuffer;
}
bool WebGLRenderbufferAttachment::valid() const
{
return m_renderbuffer->object();
}
bool WebGLRenderbufferAttachment::initialized() const
{
return m_renderbuffer->object() && m_renderbuffer->initialized();
}
void WebGLRenderbufferAttachment::setInitialized()
{
if (m_renderbuffer->object())
m_renderbuffer->setInitialized();
}
void WebGLRenderbufferAttachment::onDetached(GraphicsContext3D* context)
{
m_renderbuffer->onDetached(context);
}
void WebGLRenderbufferAttachment::attach(GraphicsContext3D* context, GC3Denum attachment)
{
Platform3DObject object = objectOrZero(m_renderbuffer.get());
if (attachment == GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT && m_renderbuffer->emulatedStencilBuffer()) {
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, object);
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, objectOrZero(m_renderbuffer->emulatedStencilBuffer()));
} else {
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, attachment, GraphicsContext3D::RENDERBUFFER, object);
}
}
void WebGLRenderbufferAttachment::unattach(GraphicsContext3D* context, GC3Denum attachment)
{
if (attachment == GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT) {
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, 0);
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, 0);
} else
context->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, attachment, GraphicsContext3D::RENDERBUFFER, 0);
}
GC3Denum WebGLRenderbufferAttachment::type() const
{
notImplemented();
return 0;
}
class WebGLTextureAttachment : public WebGLFramebuffer::WebGLAttachment {
public:
static PassRefPtr<WebGLFramebuffer::WebGLAttachment> create(WebGLTexture*, GC3Denum target, GC3Dint level);
private:
WebGLTextureAttachment(WebGLTexture*, GC3Denum target, GC3Dint level);
virtual GC3Dsizei width() const;
virtual GC3Dsizei height() const;
virtual GC3Denum format() const;
virtual GC3Denum type() const;
virtual WebGLSharedObject* object() const;
virtual bool isSharedObject(WebGLSharedObject*) const;
virtual bool valid() const;
virtual bool initialized() const;
virtual void setInitialized();
virtual void onDetached(GraphicsContext3D*);
virtual void attach(GraphicsContext3D*, GC3Denum attachment);
virtual void unattach(GraphicsContext3D*, GC3Denum attachment);
WebGLTextureAttachment() { };
RefPtr<WebGLTexture> m_texture;
GC3Denum m_target;
GC3Dint m_level;
};
PassRefPtr<WebGLFramebuffer::WebGLAttachment> WebGLTextureAttachment::create(WebGLTexture* texture, GC3Denum target, GC3Dint level)
{
return adoptRef(new WebGLTextureAttachment(texture, target, level));
}
WebGLTextureAttachment::WebGLTextureAttachment(WebGLTexture* texture, GC3Denum target, GC3Dint level)
: m_texture(texture)
, m_target(target)
, m_level(level)
{
}
GC3Dsizei WebGLTextureAttachment::width() const
{
return m_texture->getWidth(m_target, m_level);
}
GC3Dsizei WebGLTextureAttachment::height() const
{
return m_texture->getHeight(m_target, m_level);
}
GC3Denum WebGLTextureAttachment::format() const
{
return m_texture->getInternalFormat(m_target, m_level);
}
WebGLSharedObject* WebGLTextureAttachment::object() const
{
return m_texture->object() ? m_texture.get() : 0;
}
bool WebGLTextureAttachment::isSharedObject(WebGLSharedObject* object) const
{
return object == m_texture;
}
bool WebGLTextureAttachment::valid() const
{
return m_texture->object();
}
bool WebGLTextureAttachment::initialized() const
{
// Textures are assumed to be initialized.
return true;
}
void WebGLTextureAttachment::setInitialized()
{
// Textures are assumed to be initialized.
}
void WebGLTextureAttachment::onDetached(GraphicsContext3D* context)
{
m_texture->onDetached(context);
}
void WebGLTextureAttachment::attach(GraphicsContext3D* context, GC3Denum attachment)
{
Platform3DObject object = objectOrZero(m_texture.get());
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, attachment, m_target, object, m_level);
}
void WebGLTextureAttachment::unattach(GraphicsContext3D* context, GC3Denum attachment)
{
if (attachment == GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT) {
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, m_target, 0, m_level);
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, m_target, 0, m_level);
} else
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, attachment, m_target, 0, m_level);
}
GC3Denum WebGLTextureAttachment::type() const
{
return m_texture->getType(m_target, m_level);
}
bool isColorRenderable(GC3Denum internalformat)
{
switch (internalformat) {
case GraphicsContext3D::RGBA4:
case GraphicsContext3D::RGB5_A1:
case GraphicsContext3D::RGB565:
return true;
default:
return false;
}
}
} // anonymous namespace
WebGLFramebuffer::WebGLAttachment::WebGLAttachment()
{
}
WebGLFramebuffer::WebGLAttachment::~WebGLAttachment()
{
}
PassRefPtr<WebGLFramebuffer> WebGLFramebuffer::create(WebGLRenderingContext* ctx)
{
return adoptRef(new WebGLFramebuffer(ctx));
}
WebGLFramebuffer::WebGLFramebuffer(WebGLRenderingContext* ctx)
: WebGLContextObject(ctx)
, m_hasEverBeenBound(false)
{
ScriptWrappable::init(this);
setObject(ctx->graphicsContext3D()->createFramebuffer());
}
WebGLFramebuffer::~WebGLFramebuffer()
{
deleteObject(0);
}
void WebGLFramebuffer::setAttachmentForBoundFramebuffer(GC3Denum attachment, GC3Denum texTarget, WebGLTexture* texture, GC3Dint level)
{
ASSERT(isBound());
removeAttachmentFromBoundFramebuffer(attachment);
if (!object())
return;
if (texture && texture->object()) {
m_attachments.add(attachment, WebGLTextureAttachment::create(texture, texTarget, level));
drawBuffersIfNecessary(false);
texture->onAttached();
}
}
void WebGLFramebuffer::setAttachmentForBoundFramebuffer(GC3Denum attachment, WebGLRenderbuffer* renderbuffer)
{
ASSERT(isBound());
removeAttachmentFromBoundFramebuffer(attachment);
if (!object())
return;
if (renderbuffer && renderbuffer->object()) {
m_attachments.add(attachment, WebGLRenderbufferAttachment::create(renderbuffer));
drawBuffersIfNecessary(false);
renderbuffer->onAttached();
}
}
void WebGLFramebuffer::attach(GC3Denum attachment, GC3Denum attachmentPoint)
{
ASSERT(isBound());
WebGLAttachment* attachmentObject = getAttachment(attachment);
if (attachmentObject)
attachmentObject->attach(context()->graphicsContext3D(), attachmentPoint);
}
WebGLSharedObject* WebGLFramebuffer::getAttachmentObject(GC3Denum attachment) const
{
if (!object())
return 0;
WebGLAttachment* attachmentObject = getAttachment(attachment);
return attachmentObject ? attachmentObject->object() : 0;
}
bool WebGLFramebuffer::isAttachmentComplete(WebGLAttachment* attachedObject, GC3Denum attachment, const char** reason) const
{
ASSERT(attachedObject && attachedObject->valid());
ASSERT(reason);
GC3Denum internalformat = attachedObject->format();
WebGLSharedObject* object = attachedObject->object();
ASSERT(object && (object->isTexture() || object->isRenderbuffer()));
if (attachment == GraphicsContext3D::DEPTH_ATTACHMENT) {
if (object->isRenderbuffer()) {
if (internalformat != GraphicsContext3D::DEPTH_COMPONENT16) {
*reason = "the internalformat of the attached renderbuffer is not DEPTH_COMPONENT16";
return false;
}
} else if (object->isTexture()) {
GC3Denum type = attachedObject->type();
if (!(context()->m_webglDepthTexture && internalformat == GraphicsContext3D::DEPTH_COMPONENT
&& (type == GraphicsContext3D::UNSIGNED_SHORT || type == GraphicsContext3D::UNSIGNED_INT))) {
*reason = "the attached texture is not a depth texture";
return false;
}
}
} else if (attachment == GraphicsContext3D::STENCIL_ATTACHMENT) {
// Depend on the underlying GL drivers to check stencil textures
// and check renderbuffer type here only.
if (object->isRenderbuffer()) {
if (internalformat != GraphicsContext3D::STENCIL_INDEX8) {
*reason = "the internalformat of the attached renderbuffer is not STENCIL_INDEX8";
return false;
}
}
} else if (attachment == GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT) {
if (object->isRenderbuffer()) {
if (internalformat != GraphicsContext3D::DEPTH_STENCIL) {
*reason = "the internalformat of the attached renderbuffer is not DEPTH_STENCIL";
return false;
}
} else if (object->isTexture()) {
GC3Denum type = attachedObject->type();
if (!(context()->m_webglDepthTexture && internalformat == GraphicsContext3D::DEPTH_STENCIL
&& type == GraphicsContext3D::UNSIGNED_INT_24_8)) {
*reason = "the attached texture is not a DEPTH_STENCIL texture";
return false;
}
}
} else if (attachment == GraphicsContext3D::COLOR_ATTACHMENT0
|| (context()->m_webglDrawBuffers && attachment > GraphicsContext3D::COLOR_ATTACHMENT0
&& attachment < static_cast<GC3Denum>(GraphicsContext3D::COLOR_ATTACHMENT0 + context()->maxColorAttachments()))) {
if (object->isRenderbuffer()) {
if (!isColorRenderable(internalformat)) {
*reason = "the internalformat of the attached renderbuffer is not color-renderable";
return false;
}
} else if (object->isTexture()) {
GC3Denum type = attachedObject->type();
if (internalformat != GraphicsContext3D::RGBA && internalformat != GraphicsContext3D::RGB) {
*reason = "the internalformat of the attached texture is not color-renderable";
return false;
}
// TODO: WEBGL_color_buffer_float and EXT_color_buffer_half_float extensions have not been implemented in
// WebGL yet. It would be better to depend on the underlying GL drivers to check on rendering to floating point textures
// and add the check back to WebGL when above two extensions are implemented.
// Assume UNSIGNED_BYTE is renderable here without the need to explicitly check if GL_OES_rgb8_rgba8 extension is supported.
if (type != GraphicsContext3D::UNSIGNED_BYTE
&& type != GraphicsContext3D::UNSIGNED_SHORT_5_6_5
&& type != GraphicsContext3D::UNSIGNED_SHORT_4_4_4_4
&& type != GraphicsContext3D::UNSIGNED_SHORT_5_5_5_1
&& !(type == GraphicsContext3D::FLOAT && context()->m_oesTextureFloat)
&& !(type == GraphicsContext3D::HALF_FLOAT_OES && context()->m_oesTextureHalfFloat)) {
*reason = "unsupported type: The attached texture is not supported to be rendered to";
return false;
}
}
} else {
*reason = "unknown framebuffer attachment point";
return false;
}
if (!attachedObject->width() || !attachedObject->height()) {
*reason = "attachment has a 0 dimension";
return false;
}
return true;
}
WebGLFramebuffer::WebGLAttachment* WebGLFramebuffer::getAttachment(GC3Denum attachment) const
{
const AttachmentMap::const_iterator it = m_attachments.find(attachment);
return (it != m_attachments.end()) ? it->value.get() : 0;
}
void WebGLFramebuffer::removeAttachmentFromBoundFramebuffer(GC3Denum attachment)
{
ASSERT(isBound());
if (!object())
return;
WebGLAttachment* attachmentObject = getAttachment(attachment);
if (attachmentObject) {
attachmentObject->onDetached(context()->graphicsContext3D());
m_attachments.remove(attachment);
drawBuffersIfNecessary(false);
switch (attachment) {
case GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT:
attach(GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::DEPTH_ATTACHMENT);
attach(GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::STENCIL_ATTACHMENT);
break;
case GraphicsContext3D::DEPTH_ATTACHMENT:
attach(GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT, GraphicsContext3D::DEPTH_ATTACHMENT);
break;
case GraphicsContext3D::STENCIL_ATTACHMENT:
attach(GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT, GraphicsContext3D::STENCIL_ATTACHMENT);
break;
}
}
}
void WebGLFramebuffer::removeAttachmentFromBoundFramebuffer(WebGLSharedObject* attachment)
{
ASSERT(isBound());
if (!object())
return;
if (!attachment)
return;
bool checkMore = true;
while (checkMore) {
checkMore = false;
for (AttachmentMap::iterator it = m_attachments.begin(); it != m_attachments.end(); ++it) {
WebGLAttachment* attachmentObject = it->value.get();
if (attachmentObject->isSharedObject(attachment)) {
GC3Denum attachmentType = it->key;
attachmentObject->unattach(context()->graphicsContext3D(), attachmentType);
removeAttachmentFromBoundFramebuffer(attachmentType);
checkMore = true;
break;
}
}
}
}
GC3Dsizei WebGLFramebuffer::colorBufferWidth() const
{
if (!object())
return 0;
WebGLAttachment* attachment = getAttachment(GraphicsContext3D::COLOR_ATTACHMENT0);
if (!attachment)
return 0;
return attachment->width();
}
GC3Dsizei WebGLFramebuffer::colorBufferHeight() const
{
if (!object())
return 0;
WebGLAttachment* attachment = getAttachment(GraphicsContext3D::COLOR_ATTACHMENT0);
if (!attachment)
return 0;
return attachment->height();
}
GC3Denum WebGLFramebuffer::colorBufferFormat() const
{
if (!object())
return 0;
WebGLAttachment* attachment = getAttachment(GraphicsContext3D::COLOR_ATTACHMENT0);
if (!attachment)
return 0;
return attachment->format();
}
GC3Denum WebGLFramebuffer::checkStatus(const char** reason) const
{
unsigned int count = 0;
GC3Dsizei width = 0, height = 0;
bool haveDepth = false;
bool haveStencil = false;
bool haveDepthStencil = false;
for (AttachmentMap::const_iterator it = m_attachments.begin(); it != m_attachments.end(); ++it) {
WebGLAttachment* attachment = it->value.get();
if (!isAttachmentComplete(attachment, it->key, reason))
return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
if (!attachment->valid()) {
*reason = "attachment is not valid";
return GraphicsContext3D::FRAMEBUFFER_UNSUPPORTED;
}
if (!attachment->format()) {
*reason = "attachment is an unsupported format";
return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
}
switch (it->key) {
case GraphicsContext3D::DEPTH_ATTACHMENT:
haveDepth = true;
break;
case GraphicsContext3D::STENCIL_ATTACHMENT:
haveStencil = true;
break;
case GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT:
haveDepthStencil = true;
break;
}
if (!count) {
width = attachment->width();
height = attachment->height();
} else {
if (width != attachment->width() || height != attachment->height()) {
*reason = "attachments do not have the same dimensions";
return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_DIMENSIONS;
}
}
++count;
}
if (!count) {
*reason = "no attachments";
return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT;
}
if (!width || !height) {
*reason = "framebuffer has a 0 dimension";
return GraphicsContext3D::FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
}
// WebGL specific: no conflicting DEPTH/STENCIL/DEPTH_STENCIL attachments.
if ((haveDepthStencil && (haveDepth || haveStencil)) || (haveDepth && haveStencil)) {
*reason = "conflicting DEPTH/STENCIL/DEPTH_STENCIL attachments";
return GraphicsContext3D::FRAMEBUFFER_UNSUPPORTED;
}
return GraphicsContext3D::FRAMEBUFFER_COMPLETE;
}
bool WebGLFramebuffer::onAccess(GraphicsContext3D* context3d, const char** reason)
{
if (checkStatus(reason) != GraphicsContext3D::FRAMEBUFFER_COMPLETE)
return false;
return true;
}
bool WebGLFramebuffer::hasStencilBuffer() const
{
WebGLAttachment* attachment = getAttachment(GraphicsContext3D::STENCIL_ATTACHMENT);
if (!attachment)
attachment = getAttachment(GraphicsContext3D::DEPTH_STENCIL_ATTACHMENT);
return attachment && attachment->valid();
}
void WebGLFramebuffer::deleteObjectImpl(GraphicsContext3D* context3d, Platform3DObject object)
{
for (AttachmentMap::iterator it = m_attachments.begin(); it != m_attachments.end(); ++it)
it->value->onDetached(context3d);
context3d->deleteFramebuffer(object);
}
bool WebGLFramebuffer::isBound() const
{
return (context()->m_framebufferBinding.get() == this);
}
void WebGLFramebuffer::drawBuffers(const Vector<GC3Denum>& bufs)
{
m_drawBuffers = bufs;
m_filteredDrawBuffers.resize(m_drawBuffers.size());
for (size_t i = 0; i < m_filteredDrawBuffers.size(); ++i)
m_filteredDrawBuffers[i] = GraphicsContext3D::NONE;
drawBuffersIfNecessary(true);
}
void WebGLFramebuffer::drawBuffersIfNecessary(bool force)
{
if (!context()->m_webglDrawBuffers)
return;
bool reset = force;
// This filtering works around graphics driver bugs on Mac OS X.
for (size_t i = 0; i < m_drawBuffers.size(); ++i) {
if (m_drawBuffers[i] != GraphicsContext3D::NONE && getAttachment(m_drawBuffers[i])) {
if (m_filteredDrawBuffers[i] != m_drawBuffers[i]) {
m_filteredDrawBuffers[i] = m_drawBuffers[i];
reset = true;
}
} else {
if (m_filteredDrawBuffers[i] != GraphicsContext3D::NONE) {
m_filteredDrawBuffers[i] = GraphicsContext3D::NONE;
reset = true;
}
}
}
if (reset) {
context()->graphicsContext3D()->extensions()->drawBuffersEXT(
m_filteredDrawBuffers.size(), m_filteredDrawBuffers.data());
}
}
GC3Denum WebGLFramebuffer::getDrawBuffer(GC3Denum drawBuffer)
{
int index = static_cast<int>(drawBuffer - Extensions3D::DRAW_BUFFER0_EXT);
ASSERT(index >= 0);
if (index < static_cast<int>(m_drawBuffers.size()))
return m_drawBuffers[index];
if (drawBuffer == Extensions3D::DRAW_BUFFER0_EXT)
return GraphicsContext3D::COLOR_ATTACHMENT0;
return GraphicsContext3D::NONE;
}
}