New API for encoding bitmaps during serialization.

src/core/SkBitmap.cpp

Index: src/core/SkBitmap.cpp
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index fe4255d9b5e2ac41d267f62dfc178d48a12e3098..547f9acd3b7ca33afe41e8cd1e66d35cb93e7e47 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -866,18 +866,18 @@ static size_t getSubOffset(const SkBitmap& bm, int x, int y) {
  *  upper left corner of bm relative to its SkPixelRef.
  *  x and y must be non-NULL.
  */
-static bool getUpperLeftFromOffset(const SkBitmap& bm, int32_t* x, int32_t* y) {
+bool getUpperLeftFromOffset(SkBitmap::Config config, size_t offset, size_t rowBytes,
+                                   int32_t* x, int32_t* y) {
     SkASSERT(x != NULL && y != NULL);
-    const size_t offset = bm.pixelRefOffset();
     if (0 == offset) {
         *x = *y = 0;
         return true;
     }
     // Use integer division to find the correct y position.
-    *y = SkToS32(offset / bm.rowBytes());
+    *y = SkToS32(offset / rowBytes);
     // The remainder will be the x position, after we reverse getSubOffset.
-    *x = SkToS32(offset % bm.rowBytes());
-    switch (bm.getConfig()) {
+    *x = SkToS32(offset % rowBytes);
+    switch (config) {
         case SkBitmap::kA8_Config:
             // Fall through.
         case SkBitmap::kIndex8_Config:
@@ -904,6 +904,10 @@ static bool getUpperLeftFromOffset(const SkBitmap& bm, int32_t* x, int32_t* y) {
     return true;
 }
 
+static bool getUpperLeftFromOffset(const SkBitmap& bm, int32_t* x, int32_t* y) {

[djsollen, 2013/05/21 14:10:44]

according to our style guide static methods should be lower case with
underscores separating words.

[scroggo, 2013/05/21 16:14:15]

Done.

+    return getUpperLeftFromOffset(bm.config(), bm.pixelRefOffset(), bm.rowBytes(), x, y);
+}
+
 bool SkBitmap::extractSubset(SkBitmap* result, const SkIRect& subset) const {
     SkDEBUGCODE(this->validate();)