WebGLDrawBuffers.cpp [plain text]
#include "config.h"
#if ENABLE(WEBGL)
#include "WebGLDrawBuffers.h"
#include "Extensions3D.h"
namespace WebCore {
WebGLDrawBuffers::WebGLDrawBuffers(WebGLRenderingContextBase& context)
: WebGLExtension(context)
{
context.graphicsContext3D()->getExtensions().ensureEnabled("GL_EXT_draw_buffers");
}
WebGLDrawBuffers::~WebGLDrawBuffers() = default;
WebGLExtension::ExtensionName WebGLDrawBuffers::getName() const
{
return WebGLExtension::WebGLDrawBuffersName;
}
bool WebGLDrawBuffers::supported(WebGLRenderingContextBase& context)
{
#if USE(ANGLE)
return context.graphicsContext3D()->getExtensions().supports("GL_EXT_draw_buffers");
#else
return context.graphicsContext3D()->getExtensions().supports("GL_EXT_draw_buffers")
&& satisfiesWebGLRequirements(context);
#endif
}
void WebGLDrawBuffers::drawBuffersWEBGL(const Vector<GC3Denum>& buffers)
{
if (m_context.isContextLost())
return;
GC3Dsizei n = buffers.size();
const GC3Denum* bufs = buffers.data();
if (!m_context.m_framebufferBinding) {
if (n != 1) {
m_context.synthesizeGLError(GraphicsContext3D::INVALID_VALUE, "drawBuffersWEBGL", "more than one buffer");
return;
}
if (bufs[0] != GraphicsContext3D::BACK && bufs[0] != GraphicsContext3D::NONE) {
m_context.synthesizeGLError(GraphicsContext3D::INVALID_OPERATION, "drawBuffersWEBGL", "BACK or NONE");
return;
}
GC3Denum value = (bufs[0] == GraphicsContext3D::BACK) ? GraphicsContext3D::COLOR_ATTACHMENT0 : GraphicsContext3D::NONE;
m_context.graphicsContext3D()->getExtensions().drawBuffersEXT(1, &value);
m_context.setBackDrawBuffer(bufs[0]);
} else {
if (n > m_context.getMaxDrawBuffers()) {
m_context.synthesizeGLError(GraphicsContext3D::INVALID_VALUE, "drawBuffersWEBGL", "more than max draw buffers");
return;
}
for (GC3Dsizei i = 0; i < n; ++i) {
if (bufs[i] != GraphicsContext3D::NONE && bufs[i] != static_cast<GC3Denum>(Extensions3D::COLOR_ATTACHMENT0_EXT + i)) {
m_context.synthesizeGLError(GraphicsContext3D::INVALID_OPERATION, "drawBuffersWEBGL", "COLOR_ATTACHMENTi_EXT or NONE");
return;
}
}
m_context.m_framebufferBinding->drawBuffers(buffers);
}
}
bool WebGLDrawBuffers::satisfiesWebGLRequirements(WebGLRenderingContextBase& webglContext)
{
GraphicsContext3D* context = webglContext.graphicsContext3D();
GC3Dint maxDrawBuffers = 0;
GC3Dint maxColorAttachments = 0;
context->getIntegerv(Extensions3D::MAX_DRAW_BUFFERS_EXT, &maxDrawBuffers);
context->getIntegerv(Extensions3D::MAX_COLOR_ATTACHMENTS_EXT, &maxColorAttachments);
if (maxDrawBuffers < 4 || maxColorAttachments < 4)
return false;
Platform3DObject fbo = context->createFramebuffer();
context->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, fbo);
const unsigned char buffer[4] = { 0, 0, 0, 0 }; bool supportsDepth = context->getExtensions().supports("GL_OES_depth_texture")
|| context->getExtensions().supports("GL_ARB_depth_texture");
bool supportsDepthStencil = (context->getExtensions().supports("GL_EXT_packed_depth_stencil")
|| context->getExtensions().supports("GL_OES_packed_depth_stencil"));
Platform3DObject depthStencil = 0;
if (supportsDepthStencil) {
depthStencil = context->createTexture();
context->bindTexture(GraphicsContext3D::TEXTURE_2D, depthStencil);
context->texImage2D(GraphicsContext3D::TEXTURE_2D, 0, GraphicsContext3D::DEPTH_STENCIL, 1, 1, 0, GraphicsContext3D::DEPTH_STENCIL, GraphicsContext3D::UNSIGNED_INT_24_8, buffer);
}
Platform3DObject depth = 0;
if (supportsDepth) {
depth = context->createTexture();
context->bindTexture(GraphicsContext3D::TEXTURE_2D, depth);
context->texImage2D(GraphicsContext3D::TEXTURE_2D, 0, GraphicsContext3D::DEPTH_COMPONENT, 1, 1, 0, GraphicsContext3D::DEPTH_COMPONENT, GraphicsContext3D::UNSIGNED_INT, buffer);
}
Vector<Platform3DObject> colors;
bool ok = true;
GC3Dint maxAllowedBuffers = std::min(maxDrawBuffers, maxColorAttachments);
for (GC3Dint i = 0; i < maxAllowedBuffers; ++i) {
Platform3DObject color = context->createTexture();
colors.append(color);
context->bindTexture(GraphicsContext3D::TEXTURE_2D, color);
context->texImage2D(GraphicsContext3D::TEXTURE_2D, 0, GraphicsContext3D::RGBA, 1, 1, 0, GraphicsContext3D::RGBA, GraphicsContext3D::UNSIGNED_BYTE, buffer);
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::COLOR_ATTACHMENT0 + i, GraphicsContext3D::TEXTURE_2D, color, 0);
if (context->checkFramebufferStatus(GraphicsContext3D::FRAMEBUFFER) != GraphicsContext3D::FRAMEBUFFER_COMPLETE) {
ok = false;
break;
}
if (supportsDepth) {
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, depth, 0);
if (context->checkFramebufferStatus(GraphicsContext3D::FRAMEBUFFER) != GraphicsContext3D::FRAMEBUFFER_COMPLETE) {
ok = false;
break;
}
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, 0, 0);
}
if (supportsDepthStencil) {
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, depthStencil, 0);
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, depthStencil, 0);
if (context->checkFramebufferStatus(GraphicsContext3D::FRAMEBUFFER) != GraphicsContext3D::FRAMEBUFFER_COMPLETE) {
ok = false;
break;
}
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, 0, 0);
context->framebufferTexture2D(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::TEXTURE_2D, 0, 0);
}
}
webglContext.restoreCurrentFramebuffer();
context->deleteFramebuffer(fbo);
webglContext.restoreCurrentTexture2D();
if (supportsDepth)
context->deleteTexture(depth);
if (supportsDepthStencil)
context->deleteTexture(depthStencil);
for (auto& color : colors)
context->deleteTexture(color);
return ok;
}
}
#endif // ENABLE(WEBGL)