commit d63b6e4c1ebf574336cea2e4517876ba3dc67002
author Mike Klein <mtklein@chromium.org> Tue Dec 19 14:48:04 2017 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Thu Dec 21 21:28:25 2017 +0000
tree 63558466eca20ae1845146337361908be6806c14
parent 4e9a3504aaf84961c53849b4a2c7bc9746f88ab5

Reland "remove bicubic clamp in SkImageShader"

This is a reland of bc9f3499c345ce59f8cd3889c580fa75db54034b
Original change's description:
> remove bicubic clamp in SkImageShader
> 
> We ought to be able to handle out-of-gamut colors now, whatever
> their provenance.  Should be we can just not clamp here.
> 
> Bug: skia:5733
> 
> Change-Id: Icd9851543638fd81755afee2eac2347702b88e9f
> Reviewed-on: https://skia-review.googlesource.com/87000
> Commit-Queue: Mike Klein <mtklein@chromium.org>
> Reviewed-by: Brian Osman <brianosman@google.com>

Bug: skia:5733
Change-Id: I66dafdb12abdb02e8677a6f6b18602a2fa3f5f8b
Reviewed-on: https://skia-review.googlesource.com/88760
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>

src/core/SkPixmap.cpp

diff --git a/src/core/SkPixmap.cpp b/src/core/SkPixmap.cpp
index 5648405..7873a9b 100644
--- a/src/core/SkPixmap.cpp
+++ b/src/core/SkPixmap.cpp
@@ -251,10 +251,6 @@
     // Trick: if src and dst are both unpremul, we can give the correct result if we change both
     //        to premul (or opaque), since the draw will not try to blend or otherwise interpret
     //        the pixels' alpha.
-    //
-    // Today this works except in kHigh_SkFilterQuality, where we incorrectly clamp assuming the
-    // colors are premul. TODO: fix the HQ mode.
-    //
     if (srcPtr->alphaType() == kUnpremul_SkAlphaType &&
         dstPtr->alphaType() == kUnpremul_SkAlphaType)
     {

src/shaders/SkImageShader.cpp

diff --git a/src/shaders/SkImageShader.cpp b/src/shaders/SkImageShader.cpp
index ef13498..331dfb5 100644
--- a/src/shaders/SkImageShader.cpp
+++ b/src/shaders/SkImageShader.cpp
@@ -407,11 +407,13 @@
     if (info.colorType() == kAlpha_8_SkColorType || info.alphaType() == kUnpremul_SkAlphaType) {
         p->append(SkRasterPipeline::premul);
     }
+#if defined(SK_LEGACY_HIGH_QUALITY_SCALING_CLAMP)
     if (quality > kLow_SkFilterQuality) {
         // Bicubic filtering naturally produces out of range values on both sides.
         p->append(SkRasterPipeline::clamp_0);
         p->append(SkRasterPipeline::clamp_a);
     }
+#endif
     append_gamut_transform(p, alloc, info.colorSpace(), rec.fDstCS, kPremul_SkAlphaType);
     return true;
 }