gecko-dev/dom/canvas/WebGLExtensionDrawBuffers.cpp
2014-11-13 20:03:50 -08:00

89 lines
2.7 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "WebGLExtensions.h"
#include <algorithm>
#include "GLContext.h"
#include "mozilla/dom/WebGLRenderingContextBinding.h"
#include "WebGLContext.h"
#include "WebGLFramebuffer.h"
#include "WebGLRenderbuffer.h"
#include "WebGLTexture.h"
namespace mozilla {
WebGLExtensionDrawBuffers::WebGLExtensionDrawBuffers(WebGLContext* webgl)
: WebGLExtensionBase(webgl)
{
MOZ_ASSERT(IsSupported(webgl), "Don't construct extension if unsupported.");
GLint maxColorAttachments = 0;
GLint maxDrawBuffers = 0;
webgl->MakeContextCurrent();
gl::GLContext* gl = webgl->GL();
gl->fGetIntegerv(LOCAL_GL_MAX_COLOR_ATTACHMENTS, &maxColorAttachments);
gl->fGetIntegerv(LOCAL_GL_MAX_DRAW_BUFFERS, &maxDrawBuffers);
// WEBGL_draw_buffers specifications don't give a maximal value reachable by MAX_COLOR_ATTACHMENTS.
maxColorAttachments = std::min(maxColorAttachments, GLint(WebGLContext::kMaxColorAttachments));
if (webgl->MinCapabilityMode())
maxColorAttachments = std::min(maxColorAttachments, GLint(kMinColorAttachments));
// WEBGL_draw_buffers specifications request MAX_COLOR_ATTACHMENTS >= MAX_DRAW_BUFFERS.
maxDrawBuffers = std::min(maxDrawBuffers, GLint(maxColorAttachments));
webgl->mGLMaxColorAttachments = maxColorAttachments;
webgl->mGLMaxDrawBuffers = maxDrawBuffers;
}
WebGLExtensionDrawBuffers::~WebGLExtensionDrawBuffers()
{
}
void
WebGLExtensionDrawBuffers::DrawBuffersWEBGL(const dom::Sequence<GLenum>& buffers)
{
if (mIsLost) {
mContext->ErrorInvalidOperation("drawBuffersWEBGL: Extension is lost.");
return;
}
mContext->DrawBuffers(buffers);
}
bool
WebGLExtensionDrawBuffers::IsSupported(const WebGLContext* webgl)
{
gl::GLContext* gl = webgl->GL();
if (!gl->IsSupported(gl::GLFeature::draw_buffers))
return false;
GLint supportedColorAttachments = 0;
GLint supportedDrawBuffers = 0;
webgl->MakeContextCurrent();
gl->fGetIntegerv(LOCAL_GL_MAX_COLOR_ATTACHMENTS, &supportedColorAttachments);
gl->fGetIntegerv(LOCAL_GL_MAX_COLOR_ATTACHMENTS, &supportedDrawBuffers);
// WEBGL_draw_buffers requires at least 4 color attachments.
if (size_t(supportedColorAttachments) < kMinColorAttachments)
return false;
if (size_t(supportedDrawBuffers) < kMinDrawBuffers)
return false;
return true;
}
IMPL_WEBGL_EXTENSION_GOOP(WebGLExtensionDrawBuffers)
} // namespace mozilla