commit c5560bef14149f4c945a4536988aeba1a16adedc
author scroggo <scroggo@google.com> Wed Feb 03 09:42:42 2016 -0800
committer Commit bot <commit-bot@chromium.org> Wed Feb 03 09:42:42 2016 -0800
tree d62cecc289bb7c0ad9083258669179a64fd87d59
parent 8ca88e41aa76bc4da568936de9299ec3f8762d9c

Support decoding opaque to *premul

If a client requests unpremul or premul from an opaque SkCodec,
support it. The opaque image can be treated as any of them, though
it will be less efficient to draw than if the client had used
opaque.

Change the filling code (i.e. for incomplete images) to base its color on
the source alpha type. Prior to adding the support to decode opaque to
any, it was fine to use either source or dest (which would have yielded
the same result). If the client requests non-opaque, we do not want this
to switch the fill value from black to transparent. This also allows
simplifying the signatures for getFillValue and onGetFillValue.

In CodexTest, expect the same result when decoding opaque to *premul,
and compare to the opaque version.

BUG=skia:4616
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1641273003

Review URL: https://codereview.chromium.org/1641273003

dm/DMSrcSink.cpp

diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index 2988680..9712fd7 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -233,10 +233,12 @@
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
-CodecSrc::CodecSrc(Path path, Mode mode, DstColorType dstColorType, float scale)
+CodecSrc::CodecSrc(Path path, Mode mode, DstColorType dstColorType, SkAlphaType dstAlphaType,
+                   float scale)
     : fPath(path)
     , fMode(mode)
     , fDstColorType(dstColorType)
+    , fDstAlphaType(dstAlphaType)
     , fScale(scale)
 {}
 
@@ -251,30 +253,26 @@
     return flags.type != SinkFlags::kRaster || flags.approach != SinkFlags::kDirect;
 }
 
-bool get_decode_info(SkImageInfo* decodeInfo, const SkImageInfo& defaultInfo,
-        SkColorType canvasColorType, CodecSrc::DstColorType dstColorType) {
+bool get_decode_info(SkImageInfo* decodeInfo, SkColorType canvasColorType,
+                     CodecSrc::DstColorType dstColorType) {
     switch (dstColorType) {
         case CodecSrc::kIndex8_Always_DstColorType:
             if (kRGB_565_SkColorType == canvasColorType) {
                 return false;
             }
-            *decodeInfo = defaultInfo.makeColorType(kIndex_8_SkColorType);
+            *decodeInfo = decodeInfo->makeColorType(kIndex_8_SkColorType);
             break;
         case CodecSrc::kGrayscale_Always_DstColorType:
             if (kRGB_565_SkColorType == canvasColorType) {
                 return false;
             }
-            *decodeInfo = defaultInfo.makeColorType(kGray_8_SkColorType);
+            *decodeInfo = decodeInfo->makeColorType(kGray_8_SkColorType);
             break;
         default:
-            *decodeInfo = defaultInfo.makeColorType(canvasColorType);
+            *decodeInfo = decodeInfo->makeColorType(canvasColorType);
             break;
     }
 
-    // FIXME: Currently we cannot draw unpremultiplied sources.
-    if (decodeInfo->alphaType() == kUnpremul_SkAlphaType) {
-        *decodeInfo = decodeInfo->makeAlphaType(kPremul_SkAlphaType);
-    }
     return true;
 }
 
@@ -319,9 +317,8 @@
         return SkStringPrintf("Couldn't create codec for %s.", fPath.c_str());
     }
 
-    SkImageInfo decodeInfo;
-    if (!get_decode_info(&decodeInfo, codec->getInfo(), canvas->imageInfo().colorType(),
-            fDstColorType)) {
+    SkImageInfo decodeInfo = codec->getInfo().makeAlphaType(fDstAlphaType);
+    if (!get_decode_info(&decodeInfo, canvas->imageInfo().colorType(), fDstColorType)) {
         return Error::Nonfatal("Testing non-565 to 565 is uninteresting.");
     }
 
@@ -570,10 +567,11 @@
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 AndroidCodecSrc::AndroidCodecSrc(Path path, Mode mode, CodecSrc::DstColorType dstColorType,
-        int sampleSize)
+        SkAlphaType dstAlphaType, int sampleSize)
     : fPath(path)
     , fMode(mode)
     , fDstColorType(dstColorType)
+    , fDstAlphaType(dstAlphaType)
     , fSampleSize(sampleSize)
 {}
 
@@ -593,9 +591,8 @@
         return SkStringPrintf("Couldn't create android codec for %s.", fPath.c_str());
     }
 
-    SkImageInfo decodeInfo;
-    if (!get_decode_info(&decodeInfo, codec->getInfo(), canvas->imageInfo().colorType(),
-            fDstColorType)) {
+    SkImageInfo decodeInfo = codec->getInfo().makeAlphaType(fDstAlphaType);
+    if (!get_decode_info(&decodeInfo, canvas->imageInfo().colorType(), fDstColorType)) {
         return Error::Nonfatal("Testing non-565 to 565 is uninteresting.");
     }