add mipmaps to scaledimagecache

src/core/SkMipMap.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkMipMap.h"
 #include "SkBitmap.h"
 #include "SkColorPriv.h"
@@ skipping 174 matching lines @@
 
     for (int i = 0; i < countLevels; ++i) {
         width >>= 1;
         height >>= 1;
         rowBytes = SkToU32(SkBitmap::ComputeRowBytes(config, width));
 
         levels[i].fPixels   = addr;
         levels[i].fWidth    = width;
         levels[i].fHeight   = height;
         levels[i].fRowBytes = rowBytes;
+        levels[i].fScale    = (float)width / src.width();
 
         SkBitmap dstBM;
         dstBM.setConfig(config, width, height, rowBytes);
         dstBM.setPixels(addr);
 
         srcBM.lockPixels();
         for (int y = 0; y < height; y++) {
             for (int x = 0; x < width; x++) {
                 proc(&dstBM, x, y, srcBM);
             }
         }
         srcBM.unlockPixels();
 
         srcBM = dstBM;
         addr += height * rowBytes;
     }
     SkASSERT(addr == baseAddr + size);
 
-    return SkNEW_ARGS(SkMipMap, (levels, countLevels));
+    return SkNEW_ARGS(SkMipMap, (levels, countLevels, size));
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+//static int gCounter;
+
+SkMipMap::SkMipMap(Level* levels, int count, size_t size)
+    : fSize(size), fLevels(levels), fCount(count) {
+    SkASSERT(levels);
+    SkASSERT(count > 0);
+//    SkDebugf("mips %d\n", ++gCounter);
+}
+
+SkMipMap::~SkMipMap() {
+    sk_free(fLevels);
+//    SkDebugf("mips %d\n", --gCounter);
 }
 
 static SkFixed compute_level(SkScalar scale) {
     SkFixed s = SkAbs32(SkScalarToFixed(SkScalarInvert(scale)));
 
     if (s < SK_Fixed1) {
         return 0;
     }
     int clz = SkCLZ(s);
     SkASSERT(clz >= 1 && clz <= 15);
@@ skipping 12 matching lines @@
     }
 
     if (level > fCount) {
         level = fCount;
     }
     if (levelPtr) {
         *levelPtr = fLevels[level - 1];
     }
     return true;
 }