Proactive SkPixelRef invalidation

src/core/SkBitmap.cpp

Index: src/core/SkBitmap.cpp
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index 05f5208a69bfd62fba985d9f2e54e59d4853bb0d..14487ac136e05d35cea12a28f028080b3342fa55 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -1056,7 +1056,7 @@ bool SkBitmap::copyTo(SkBitmap* dst, Config dstConfig, Allocator* alloc) const {
                 if (tmpSrc.config() == dstConfig && NULL == alloc) {
                     dst->swap(tmpSrc);
                     if (dst->pixelRef() && this->config() == dstConfig) {
-                        dst->pixelRef()->fGenerationID = fPixelRef->getGenerationID();
+                        dst->pixelRef()->cloneGenID(*fPixelRef);

[scroggo, 2013/10/22 21:04:02]

So this patch does not address the bug we discussed earlier that the ID gets
cloned even if we're looking at a subset? Can you add a FIXME that we know
there's a bug (or fix it)?

[bsalomon, 2013/10/23 13:52:57]

I'd prefer keeping a fix for that as a separate issue.

[mtklein, 2013/10/23 15:28:10]

Added skia:1742.

[scroggo, 2013/10/23 15:39:19]

I still think it would be nice to document this in the code. Thanks for adding
skia:1742; I think it should be referenced in a comment. The bug references line
1058 may be less meaningful in the future if the code moves.

[mtklein, 2013/10/23 16:07:10]

Done.

                     }
                     return true;
                 }
@@ -1096,8 +1096,8 @@ bool SkBitmap::copyTo(SkBitmap* dst, Config dstConfig, Allocator* alloc) const {
         if (tmpDst.getSize() == src->getSize()) {
             memcpy(tmpDst.getPixels(), src->getPixels(), src->getSafeSize());
             SkPixelRef* pixelRef = tmpDst.pixelRef();
-            if (pixelRef != NULL) {
-                pixelRef->fGenerationID = this->getGenerationID();
+            if (pixelRef != NULL && fPixelRef != NULL) {

[bsalomon, 2013/10/23 13:52:57]

ubernbit: NULL != pixelRef

[mtklein, 2013/10/23 15:28:10]

Done.

+                pixelRef->cloneGenID(*fPixelRef);
             }
         } else {
             const char* srcP = reinterpret_cast<const char*>(src->getPixels());
@@ -1151,7 +1151,7 @@ bool SkBitmap::deepCopyTo(SkBitmap* dst, Config dstConfig) const {
         if (pixelRef) {
             uint32_t rowBytes;
             if (dstConfig == fConfig) {
-                pixelRef->fGenerationID = fPixelRef->getGenerationID();
+                pixelRef->cloneGenID(*fPixelRef);
                 // Use the same rowBytes as the original.
                 rowBytes = fRowBytes;
             } else {