[WIP] Plumbing for paint

third_party/WebKit/Source/modules/csspaint/CSSPaintDefinition.cpp

+// Copyright 2016 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 "modules/csspaint/CSSPaintDefinition.h"
+
+#include "bindings/core/v8/ScriptState.h"
+#include "bindings/core/v8/V8Binding.h"
+#include "core/dom/ExecutionContext.h"
+#include "core/frame/ConsoleTypes.h"
+#include "core/inspector/ConsoleMessage.h"
+#include "modules/csspaint/PaintRenderingContext2D.h"
+#include "platform/graphics/ImageBuffer.h"
+#include "platform/graphics/PaintGeneratedImage.h"
+#include "platform/graphics/RecordingImageBufferSurface.h"
+#include "platform/graphics/UnacceleratedImageBufferSurface.h"
+
+namespace blink {
+
+namespace {
+
+class UnacceleratedSurfaceFactory : public RecordingImageBufferFallbackSurfaceFactory {
+public:
+    virtual PassOwnPtr<ImageBufferSurface> createSurface(const IntSize& size, OpacityMode opacityMode)
+    {
+        // ASSERT_NOT_REACHED();
+        // return nullptr;
+        return adoptPtr(new UnacceleratedImageBufferSurface(size, opacityMode));
+    }
+
+    virtual ~UnacceleratedSurfaceFactory() { }
+};
+
+} // namespace
+
+PassRefPtrWillBeRawPtr<CSSPaintDefinition> CSSPaintDefinition::create(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint)
+{
+    return adoptRefWillBeNoop(new CSSPaintDefinition(scriptState, constructor, paint));
+}
+
+CSSPaintDefinition::CSSPaintDefinition(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint)
+    : m_scriptState(scriptState)
+    , m_constructor(scriptState->isolate(), constructor)
+    , m_paint(scriptState->isolate(), paint)
+{
+}
+
+CSSPaintDefinition::~CSSPaintDefinition()
+{
+}
+
+PassRefPtr<Image> CSSPaintDefinition::paint(const IntSize& size)
+{
+    v8::Isolate* isolate = m_scriptState->isolate();
+
+    ScriptState::Scope scope(m_scriptState.get());
+    v8::MicrotasksScope microtasksScope(isolate, v8::MicrotasksScope::kRunMicrotasks);
+
+    v8::Local<v8::Object> instance = paintInstance();
+    if (isUndefinedOrNull(instance))
+        return nullptr;
+
+    OwnPtrWillBeRawPtr<PaintRenderingContext2D> renderingContext = PaintRenderingContext2D::create(
+        ImageBuffer::create(adoptPtr(new RecordingImageBufferSurface(size, adoptPtr(new UnacceleratedSurfaceFactory())))));
+
+    v8::Local<v8::Value> argv[] = {
+        toV8(renderingContext, m_scriptState->context()->Global(), isolate),
+        toV8(size.width(), m_scriptState->context()->Global(), isolate),
+        toV8(size.height(), m_scriptState->context()->Global(), isolate)
+    };
+
+    v8::Local<v8::Function> paint = m_paint.newLocal(isolate);
+
+    v8::TryCatch exceptionCatcher(isolate);
+    paint->Call(instance, 3, argv);
+
+    // TODO(ikilpatrick): error message if everything break, saaad trombone.
+    return PaintGeneratedImage::create(renderingContext->imageBuffer()->getPicture(), size);
+}
+
+v8::Local<v8::Object> CSSPaintDefinition::paintInstance()
+{
+    if (m_instance.isEmpty()) {
+        v8::Local<v8::Function> constructor = m_constructor.newLocal(m_scriptState->isolate());
+        ASSERT(!isUndefinedOrNull(constructor));
+
+        v8::Local<v8::Object> paintInstance;
+        if (!constructor->NewInstance(m_scriptState->context()).ToLocal(&paintInstance)) {
+            m_scriptState->getExecutionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, "Failed to create instance of class."));
+        }
+
+        return paintInstance;
+    }
+
+    return m_instance.newLocal(m_scriptState->isolate());
+}
+
+} // namespace blink