webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 170 insertions, 0 deletions

diff --git a/Source/WebCore/html/canvas/WebGLDrawBuffers.cpp b/Source/WebCore/html/canvas/WebGLDrawBuffers.cpp
new file mode 100644
index 000000000..0891c02a9
--- /dev/null
+++ b/Source/WebCore/html/canvas/WebGLDrawBuffers.cpp
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2013 Google 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 AND ITS CONTRIBUTORS "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 OR ITS 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"
+
+#if ENABLE(WEBGL)
+#include "WebGLDrawBuffers.h"
+
+#include "Extensions3D.h"
+
+namespace WebCore {
+
+WebGLDrawBuffers::WebGLDrawBuffers(WebGLRenderingContextBase& context)
+    : WebGLExtension(context)
+{
+}
+
+WebGLDrawBuffers::~WebGLDrawBuffers()
+{
+}
+
+WebGLExtension::ExtensionName WebGLDrawBuffers::getName() const
+{
+    return WebGLExtension::WebGLDrawBuffersName;
+}
+
+bool WebGLDrawBuffers::supported(WebGLRenderingContextBase& context)
+{
+    return context.graphicsContext3D()->getExtensions().supports("GL_EXT_draw_buffers")
+        && satisfiesWebGLRequirements(context);
+}
+
+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;
+        }
+        // Because the backbuffer is simulated on all current WebKit ports, we need to change BACK to COLOR_ATTACHMENT0.
+        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);
+    }
+}
+
+// static
+bool WebGLDrawBuffers::satisfiesWebGLRequirements(WebGLRenderingContextBase& webglContext)
+{
+    GraphicsContext3D* context = webglContext.graphicsContext3D();
+
+    // This is called after we make sure GL_EXT_draw_buffers is supported.
+    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 }; // textures are required to be initialized for other ports.
+    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;
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(WEBGL)