[SVG] DisplayList-based patterns.

Source/platform/graphics/DisplayListPattern.cpp

+// Copyright 2014 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 "platform/graphics/DisplayListPattern.h"
+
+#include "platform/graphics/DisplayList.h"
+#include "platform/graphics/skia/SkiaUtils.h"
+#include "third_party/skia/include/core/SkShader.h"
+
+namespace blink {
+
+DisplayListPattern::DisplayListPattern(PassRefPtr<DisplayList> displayList, RepeatMode mode)
+    : Pattern(mode)
+    , m_tileDisplayList(displayList)
+{
+    // All current clients use RepeatModeXY, so we only support this mode for now.
+    ASSERT(isRepeatXY());
+
+    // FIXME: we don't have a good way to account for DL memory utilization.
+}
+
+DisplayListPattern::~DisplayListPattern()
+{
+}
+
+PassRefPtr<SkShader> DisplayListPattern::createShader()
+{
+    SkMatrix localMatrix = affineTransformToSkMatrix(m_patternSpaceTransformation);
+    SkRect tileBounds = SkRect::MakeWH(m_tileDisplayList->bounds().width(),
+        m_tileDisplayList->bounds().height());
+
+    return adoptRef(SkShader::CreatePictureShader(m_tileDisplayList->picture(),
+        SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode, &localMatrix, &tileBounds));
+}
+
+} // namespace