Add Sample slide for Rectanizers

src/gpu/GrRectanizer.h

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrRectanizer_DEFINED
 #define GrRectanizer_DEFINED
 
 #include "GrPoint.h"
 
 class GrRectanizer {
 public:
     GrRectanizer(int width, int height) : fWidth(width), fHeight(height) {
         SkASSERT(width >= 0);
         SkASSERT(height >= 0);
     }
 
     virtual ~GrRectanizer() {}
 
     virtual void reset() = 0;
 
     int width() const { return fWidth; }
     int height() const { return fHeight; }
 
+    // Attempt to add a rect. Return true on success; false on failure. If
+    // successful the position in the atlas is returned in 'loc'.
     virtual bool addRect(int width, int height, GrIPoint16* loc) = 0;
     virtual float percentFull() const = 0;
 
     /**
      *  Our factory, which returns the subclass du jour
      */
     static GrRectanizer* Factory(int width, int height);
 
 private:
     int fWidth;
     int fHeight;
 };
 
 #endif