1 files changed, 116 insertions, 0 deletions
diff --git a/Source/WebKit2/WebProcess/WebPage/CoordinatedGraphics/UpdateAtlas.cpp b/Source/WebKit2/WebProcess/WebPage/CoordinatedGraphics/UpdateAtlas.cpp
new file mode 100644
index 000000000..e2c4ffeee
--- /dev/null
+++ b/Source/WebKit2/WebProcess/WebPage/CoordinatedGraphics/UpdateAtlas.cpp
@@ -0,0 +1,116 @@
+/*
+ Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies)
+ Copyright (C) 2012 Company 100, Inc.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
+ along with this library; see the file COPYING.LIB.  If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
+ */
+
+#include "config.h"
+#include "UpdateAtlas.h"
+
+#if USE(COORDINATED_GRAPHICS)
+
+#include <WebCore/CoordinatedGraphicsState.h>
+#include <WebCore/GraphicsContext.h>
+#include <WebCore/IntRect.h>
+#include <wtf/MathExtras.h>
+
+using namespace WebCore;
+
+namespace WebKit {
+
+class UpdateAtlasSurfaceClient final : public CoordinatedSurface::Client {
+public:
+    UpdateAtlasSurfaceClient(CoordinatedSurface::Client& client, const IntSize& size, bool supportsAlpha)
+        : m_client(client)
+        , m_size(size)
+        , m_supportsAlpha(supportsAlpha)
+    {
+    }
+
+    void paintToSurfaceContext(GraphicsContext& context) override
+    {
+        if (m_supportsAlpha) {
+            context.setCompositeOperation(CompositeCopy);
+            context.fillRect(IntRect(IntPoint::zero(), m_size), Color::transparent);
+            context.setCompositeOperation(CompositeSourceOver);
+        }
+
+        m_client.paintToSurfaceContext(context);
+    }
+
+private:
+    CoordinatedSurface::Client& m_client;
+    IntSize m_size;
+    bool m_supportsAlpha;
+};
+
+UpdateAtlas::UpdateAtlas(Client& client, int dimension, CoordinatedSurface::Flags flags)
+    : m_client(client)
+{
+    static uint32_t nextID = 0;
+    m_ID = ++nextID;
+    IntSize size = nextPowerOfTwo(IntSize(dimension, dimension));
+    m_surface = CoordinatedSurface::create(size, flags);
+
+    m_client.createUpdateAtlas(m_ID, m_surface.copyRef());
+}
+
+UpdateAtlas::~UpdateAtlas()
+{
+    if (m_surface)
+        m_client.removeUpdateAtlas(m_ID);
+}
+
+void UpdateAtlas::buildLayoutIfNeeded()
+{
+    if (m_areaAllocator)
+        return;
+    m_areaAllocator = std::make_unique<GeneralAreaAllocator>(size());
+    m_areaAllocator->setMinimumAllocation(IntSize(32, 32));
+}
+
+void UpdateAtlas::didSwapBuffers()
+{
+    m_areaAllocator = nullptr;
+}
+
+bool UpdateAtlas::paintOnAvailableBuffer(const IntSize& size, uint32_t& atlasID, IntPoint& offset, CoordinatedSurface::Client& client)
+{
+    m_inactivityInSeconds = 0;
+    buildLayoutIfNeeded();
+    IntRect rect = m_areaAllocator->allocate(size);
+
+    // No available buffer was found.
+    if (rect.isEmpty())
+        return false;
+
+    if (!m_surface)
+        return false;
+
+    atlasID = m_ID;
+
+    // FIXME: Use tri-state buffers, to allow faster updates.
+    offset = rect.location();
+
+    UpdateAtlasSurfaceClient surfaceClient(client, size, supportsAlpha());
+    m_surface->paintToSurface(rect, surfaceClient);
+
+    return true;
+}
+
+} // namespace WebCore
+#endif // USE(COORDINATED_GRAPHICS)