Adding Blink bindings for WebGL 2

Source/core/html/canvas/WebGL2RenderingContext.cpp

+// Copyright 2015 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 "config.h"
+#include "core/html/canvas/WebGL2RenderingContext.h"
+
+#include "core/frame/LocalFrame.h"
+#include "core/frame/Settings.h"
+#include "core/html/canvas/ContextAttributeHelpers.h"
+#include "core/html/canvas/WebGLContextAttributes.h"
+#include "core/html/canvas/WebGLContextEvent.h"
+#include "core/html/canvas/WebGLDebugRendererInfo.h"
+#include "core/html/canvas/WebGLDebugShaders.h"
+#include "core/loader/FrameLoader.h"
+#include "core/loader/FrameLoaderClient.h"
+#include "platform/graphics/gpu/DrawingBuffer.h"
+#include "public/platform/Platform.h"
+
+namespace blink {
+
+static bool shouldFailContextCreationForTesting = false;
+
+PassOwnPtr<WebGL2RenderingContext> WebGL2RenderingContext::create(HTMLCanvasElement* canvas, const CanvasContextCreationAttributes& attrs)
+{
+    if (!RuntimeEnabledFeatures::unsafeES3APIsEnabled()) {
+        canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Creation of WebGL2 contexts disabled."));
+        return nullptr;
+    }
+
+    Document& document = canvas->document();
+    LocalFrame* frame = document.frame();
+    if (!frame) {
+        canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Web page was not allowed to create a WebGL2 context."));
+        return nullptr;
+    }
+    Settings* settings = frame->settings();
+
+    // The FrameLoaderClient might block creation of a new WebGL context despite the page settings; in
+    // particular, if WebGL contexts were lost one or more times via the GL_ARB_robustness extension.
+    if (!frame->loader().client()->allowWebGL(settings && settings->webGLEnabled())) {
+        canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Web page was not allowed to create a WebGL2 context."));
+        return nullptr;
+    }
+
+    WebGLContextAttributes attributes = toWebGLContextAttributes(attrs);
+    blink::WebGraphicsContext3D::Attributes wgc3dAttributes = toWebGraphicsContext3DAttributes(attributes, document.topDocument().url().string(), settings, 2);
+    blink::WebGLInfo glInfo;
+    OwnPtr<blink::WebGraphicsContext3D> context = adoptPtr(blink::Platform::current()->createOffscreenGraphicsContext3D(wgc3dAttributes, 0, &glInfo));
+    if (!context || shouldFailContextCreationForTesting) {
+        shouldFailContextCreationForTesting = false;

[Ken Russell (switch to Gerrit), 2015/02/03 01:23:24]

Please refactor this boilerplate error handling code to share it between the
WebGL 1 and 2 contexts.

+        String statusMessage;
+        if (!glInfo.contextInfoCollectionFailure.isEmpty()) {
+            statusMessage.append("Could not create a WebGL2 context. ");
+            statusMessage.append(glInfo.contextInfoCollectionFailure);
+        } else {
+            statusMessage.append("Could not create a WebGL2 context");
+            if (!glInfo.vendorInfo.isEmpty()) {
+                statusMessage.append(" VendorInfo = ");
+                statusMessage.append(glInfo.vendorInfo);
+            } else {
+                statusMessage.append(" VendorInfo = Not Available");
+            }
+            if (!glInfo.rendererInfo.isEmpty()) {
+                statusMessage.append(", RendererInfo = ");
+                statusMessage.append(glInfo.rendererInfo);
+            } else {
+                statusMessage.append(", RendererInfo = Not Available");
+            }
+            if (!glInfo.driverVersion.isEmpty()) {
+                statusMessage.append(", DriverInfo = ");
+                statusMessage.append(glInfo.driverVersion);
+            } else {
+                statusMessage.append(", DriverInfo = Not Available");
+            }
+            statusMessage.append(".");
+        }
+        canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, statusMessage));
+        return nullptr;
+    }
+
+    OwnPtr<Extensions3DUtil> extensionsUtil = Extensions3DUtil::create(context.get());
+    if (!extensionsUtil)
+        return nullptr;
+    if (extensionsUtil->supportsExtension("GL_EXT_debug_marker")) {
+        String contextLabel(String::format("WebGL2RenderingContext-%p", context.get()));
+        context->pushGroupMarkerEXT(contextLabel.ascii().data());
+    }
+
+    OwnPtrWillBeRawPtr<WebGL2RenderingContext> renderingContext = adoptPtrWillBeNoop(new WebGL2RenderingContext(canvas, context.release(), attributes));
+    renderingContext->registerContextExtensions();
+    renderingContext->suspendIfNeeded();
+
+    if (!renderingContext->drawingBuffer()) {
+        canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Could not create a WebGL2 context."));
+        return nullptr;
+    }
+
+    return renderingContext.release();
+}
+
+WebGL2RenderingContext::WebGL2RenderingContext(HTMLCanvasElement* passedCanvas, PassOwnPtr<blink::WebGraphicsContext3D> context, const WebGLContextAttributes& requestedAttributes)
+    : WebGL2RenderingContextBase(passedCanvas, context, requestedAttributes)
+{
+}
+
+WebGL2RenderingContext::~WebGL2RenderingContext()
+{
+
+}
+
+void WebGL2RenderingContext::registerContextExtensions()
+{
+    // Register privileged extensions.
+    registerExtension<WebGLDebugRendererInfo>(m_webglDebugRendererInfo);
+    registerExtension<WebGLDebugShaders>(m_webglDebugShaders);
+}
+
+void WebGL2RenderingContext::trace(Visitor* visitor)
+{
+    visitor->trace(m_webglDebugRendererInfo);
+    visitor->trace(m_webglDebugShaders);
+    WebGL2RenderingContextBase::trace(visitor);
+}
+
+void WebGL2RenderingContext::forceNextWebGLContextCreationToFail()
+{
+    shouldFailContextCreationForTesting = true;
+}
+
+} // namespace blink