Support Float32 output from SkColorSpaceXform

src/codec/SkPngCodec.cpp

Index: src/codec/SkPngCodec.cpp
diff --git a/src/codec/SkPngCodec.cpp b/src/codec/SkPngCodec.cpp
index 0002bc5a31b922eb1e869bc20f9eb6c2440f7886..d6366d3b396417f3026ec3e34b154b0d252e4113 100644
--- a/src/codec/SkPngCodec.cpp
+++ b/src/codec/SkPngCodec.cpp
@@ -149,11 +149,12 @@ bool SkPngCodec::createColorTable(const SkImageInfo& dstInfo, int* ctableCount)
     // If we are not decoding to F16, we can color xform now and store the results
     // in the color table.
     if (fColorXform && kRGBA_F16_SkColorType != dstInfo.colorType()) {
-        SkColorType xformColorType = is_rgba(dstInfo.colorType()) ?
-                kRGBA_8888_SkColorType : kBGRA_8888_SkColorType;
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
+        SkColorSpaceXform::ColorFormat xformColorFormat = is_rgba(dstInfo.colorType()) ?
+                SkColorSpaceXform::kRGBA_8888_ColorFormat :
+                SkColorSpaceXform::kBGRA_8888_ColorFormat;
+        SkAlphaType xformAlphaType = select_xform_alpha(dstInfo.alphaType(),
                                                         this->getInfo().alphaType());
-        fColorXform->apply(colorTable, colorTable, numColors, xformColorType, xformAlphaType);
+        fColorXform->apply(colorTable, colorTable, numColors, xformColorFormat, xformAlphaType);
     }
 
     // Pad the color table with the last color in the table (or black) in the case that
@@ -380,16 +381,17 @@ void SkPngCodec::allocateStorage(const SkImageInfo& dstInfo) {
 
 void SkPngCodec::applyXformRow(void* dst, const void* src, SkColorType colorType,
                                SkAlphaType alphaType, int width) {
+    SkColorSpaceXform::ColorFormat colorFormat = select_xform_format(colorType);

[msarett, 2016/09/14 20:20:35]

Leon, ideally your PNG change can land first?  I think this will refactor nicer
under your design.

[scroggo, 2016/09/14 20:35:01]

That depends. How much of a hurry are you to get this in?

I saw an error on the bots that I have figured out how to repro locally, but I'm
still investigating. (It happens in a webp image, which should not be affected
by my changes...)

Once that's fixed, I still need to update Google3, unless we can work around it.
Given the lack of progress there (taviso@ and clay@ have not been responsive) it
might be worth trying to get an exception for using our own copy of the library.
It won't get us off the hook for updating it, but it can give us some more time
to do so.

[msarett, 2016/09/14 21:09:43]

I'll probably want to write some stuff based on this, but I won't rush it until
I have a queue.
IMHO if you're blocked by waiting on code reviews, we might as well reland the
special Skia copy.  When someone complains it might be a good way to ping the
review.

     switch (fXformMode) {
         case kSwizzleOnly_XformMode:
             fSwizzler->swizzle(dst, (const uint8_t*) src);
             break;
         case kColorOnly_XformMode:
-            fColorXform->apply(dst, (const uint32_t*) src, width, colorType, alphaType);
+            fColorXform->apply(dst, (const uint32_t*) src, width, colorFormat, alphaType);
             break;
         case kSwizzleColor_XformMode:
             fSwizzler->swizzle(fColorXformSrcRow, (const uint8_t*) src);
-            fColorXform->apply(dst, fColorXformSrcRow, width, colorType, alphaType);
+            fColorXform->apply(dst, fColorXformSrcRow, width, colorFormat, alphaType);
             break;
     }
 }
@@ -425,7 +427,7 @@ public:
             return y;
         }
 
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
+        SkAlphaType xformAlphaType = select_xform_alpha(dstInfo.alphaType(),
                                                         this->getInfo().alphaType());
         int width = fSwizzler ? fSwizzler->swizzleWidth() : dstInfo.width();
 
@@ -511,7 +513,7 @@ public:
             }
         }
 
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
+        SkAlphaType xformAlphaType = select_xform_alpha(dstInfo.alphaType(),
                                                         this->getInfo().alphaType());
         int width = fSwizzler ? fSwizzler->swizzleWidth() : dstInfo.width();
         srcRow = storage.get();
@@ -902,7 +904,7 @@ SkCodec::Result SkPngCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst,
 uint64_t SkPngCodec::onGetFillValue(const SkImageInfo& dstInfo) const {
     const SkPMColor* colorPtr = get_color_ptr(fColorTable.get());
     if (colorPtr) {
-        SkAlphaType alphaType = select_alpha_xform(dstInfo.alphaType(),
+        SkAlphaType alphaType = select_xform_alpha(dstInfo.alphaType(),
                                                    this->getInfo().alphaType());
         return get_color_table_fill_value(dstInfo.colorType(), alphaType, colorPtr, 0,
                                           fColorXform.get());