Optimize Complex Text Shaping and Caching

Source/platform/fonts/shaping/CachingWordShaper.h

 /*
- * Copyright (C) 2011 Google, Inc. All Rights Reserved.
+ * Copyright (C) 2015 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef LocalFrameLifecycleObserver_h
-#define LocalFrameLifecycleObserver_h
+#ifndef CachingWordShaper_h
+#define CachingWordShaper_h
 
-#include "core/CoreExport.h"
-#include "core/frame/LocalFrame.h"
-#include "platform/LifecycleObserver.h"
-#include "platform/heap/Handle.h"
+
+#include "platform/geometry/FloatRect.h"
+#include "platform/text/TextRun.h"
+#include "wtf/PassRefPtr.h"
 
 namespace blink {
 
-class LocalFrame;
-class LocalFrameLifecycleNotifier;
+class Font;
+class GlyphBuffer;
+class SimpleFontData;
+class ShapeCache;
+struct GlyphData;
 
-class CORE_EXPORT LocalFrameLifecycleObserver : public LifecycleObserver<LocalFrame, LocalFrameLifecycleObserver, LocalFrameLifecycleNotifier> {
+class PLATFORM_EXPORT CachingWordShaper final {
 public:
-    virtual void willDetachFrameHost() { }
-    virtual void contextDestroyed()
-    {
-        setContext(nullptr);
-    }
+    CachingWordShaper();
+    ~CachingWordShaper();
+    void clear();
 
-    LocalFrame* frame() const { return lifecycleContext(); }
+    float width(const Font*, const TextRun&,
+        HashSet<const SimpleFontData*>* fallbackFonts,
+        FloatRect* glyphBounds);
+    float fillGlyphBuffer(const Font*, const TextRun&,
+        HashSet<const SimpleFontData*>*, GlyphBuffer*,
+        unsigned from, unsigned to);
 
-protected:
-    explicit LocalFrameLifecycleObserver(LocalFrame* frame)
-        : LifecycleObserver(frame)
-    {
-    }
+    private:
+        ShapeCache* m_shapeCache;
 };
 
 } // namespace blink
 
-#endif // LocalFrameLifecycleObserver_h
+#endif // CachingWordShaper_h