Integrate custom paint with the DocumentLifecycle

sky/engine/core/painting/PaintingTasks.cpp

Index: sky/engine/core/painting/PaintingTasks.cpp
diff --git a/sky/engine/core/painting/PaintingTasks.cpp b/sky/engine/core/painting/PaintingTasks.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..e266eafc5b20d830a3193efcc59102dcfeed0c60
--- /dev/null
+++ b/sky/engine/core/painting/PaintingTasks.cpp
@@ -0,0 +1,98 @@
+// 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 "sky/engine/config.h"
+#include "sky/engine/core/painting/PaintingTasks.h"
+
+#include "sky/engine/core/dom/Element.h"
+#include "sky/engine/core/painting/PaintingCallback.h"
+#include "sky/engine/core/painting/PaintingContext.h"
+#include "sky/engine/core/rendering/RenderBox.h"
+#include "sky/engine/platform/graphics/DisplayList.h"
+#include "sky/engine/wtf/OwnPtr.h"
+#include "sky/engine/wtf/RefPtr.h"
+#include "sky/engine/wtf/Vector.h"
+
+namespace blink {
+namespace {
+
+struct RequestTask {
+    RequestTask(PassRefPtr<Element> e, PassOwnPtr<PaintingCallback> c)
+        : element(e), callback(c) { }
+
+    RefPtr<Element> element;
+    OwnPtr<PaintingCallback> callback;
+
+    // Used during serviceRequests.
+    RefPtr<PaintingContext> context;
+};
+
+struct CommitTask {
+    CommitTask(PassRefPtr<Element> e, PassRefPtr<DisplayList> d)
+        : element(e), displayList(d) { }
+
+    RefPtr<Element> element;
+    RefPtr<DisplayList> displayList;
+};
+
+static Vector<OwnPtr<RequestTask>>& requests()
+{
+    DEFINE_STATIC_LOCAL(OwnPtr<Vector<OwnPtr<RequestTask>>>, queue, (adoptPtr(new Vector<OwnPtr<RequestTask>>())));
+    return *queue;
+}
+
+static Vector<CommitTask>& commits()
+{
+    DEFINE_STATIC_LOCAL(OwnPtr<Vector<CommitTask>>, queue, (adoptPtr(new Vector<CommitTask>())));
+    return *queue;
+}
+
+} // namespace
+
+void PaintingTasks::enqueueRequest(PassRefPtr<Element> element, PassOwnPtr<PaintingCallback> callback)
+{
+    requests().append(adoptPtr(new RequestTask(element, callback)));
+}
+
+void PaintingTasks::enqueueCommit(PassRefPtr<Element> element, PassRefPtr<DisplayList> displayList)
+{
+    commits().append(CommitTask(element, displayList));
+}
+
+bool PaintingTasks::serviceRequests()
+{
+    if (requests().isEmpty())
+        return false;
+
+    for (auto& request : requests()) {
+        RenderObject* renderer = request->element->renderer();
+        if (!renderer || !renderer->isBox())
+            continue;
+        request->context = PaintingContext::create(request->element, toRenderBox(renderer)->size());
+    }
+
+    Vector<OwnPtr<RequestTask>> local;
+    swap(requests(), local);
+    for (const auto& request : local) {
+        if (!request->context)
+            continue;
+        request->callback->handleEvent(request->context.get());
+    }
+
+    return true;
+}
+
+void PaintingTasks::drainCommits()
+{
+    for (auto& commit : commits()) {
+        RenderObject* renderer = commit.element->renderer();
+        if (!renderer || !renderer->isBox())
+            return;
+        toRenderBox(renderer)->setCustomPainting(commit.displayList.release());
+    }
+
+    commits().clear();
+}
+
+} // namespace blink