commit 5a7ae7e337a68dc42723fce80752c93b7d26d469
author brianosman <brianosman@google.com> Mon Sep 12 12:07:25 2016 -0700
committer Commit bot <commit-bot@chromium.org> Mon Sep 12 12:07:25 2016 -0700
tree 24ebe49dc9e9dc4f7e9e032f2106aaa622596a0f
parent 6ade6dd9910be25c15e25c90d76f8471ff23f62c

Gamut transformation of the paint color in Ganesh

Conversion from sRGB to destination gamut is going to be very common,
so I'm caching that xform (if there is one) on the draw context.

Results verified in the gamut GM (two more boxes correct).

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2330553003

Review-Url: https://codereview.chromium.org/2330553003

include/gpu/GrColorSpaceXform.h

diff --git a/include/gpu/GrColorSpaceXform.h b/include/gpu/GrColorSpaceXform.h
index 38b5ccf..2d2cc86 100644
--- a/include/gpu/GrColorSpaceXform.h
+++ b/include/gpu/GrColorSpaceXform.h
@@ -8,6 +8,7 @@
 #ifndef GrColorSpaceXform_DEFINED
 #define GrColorSpaceXform_DEFINED
 
+#include "GrColor.h"
 #include "SkMatrix44.h"
 #include "SkRefCnt.h"
 
@@ -33,6 +34,8 @@
         return SkToBool(xform) ? 1 : 0;
     }
 
+    GrColor4f apply(const GrColor4f& srcColor);
+
 private:
     SkMatrix44 fSrcToDst;
 };

include/gpu/GrDrawContext.h

diff --git a/include/gpu/GrDrawContext.h b/include/gpu/GrDrawContext.h
index cad2b82..29a70f9 100644
--- a/include/gpu/GrDrawContext.h
+++ b/include/gpu/GrDrawContext.h
@@ -335,6 +335,7 @@
     }
     const SkSurfaceProps& surfaceProps() const { return fSurfaceProps; }
     SkColorSpace* getColorSpace() const { return fColorSpace.get(); }
+    GrColorSpaceXform* getColorXformFromSRGB() const { return fColorXformFromSRGB.get(); }
     GrSurfaceOrigin origin() const { return fRenderTarget->origin(); }
 
     bool wasAbandoned() const;
@@ -425,6 +426,7 @@
     GrInstancedPipelineInfo           fInstancedPipelineInfo;
 
     sk_sp<SkColorSpace>               fColorSpace;
+    sk_sp<GrColorSpaceXform>          fColorXformFromSRGB;
     SkSurfaceProps                    fSurfaceProps;
     GrAuditTrail*                     fAuditTrail;
 

src/gpu/GrColorSpaceXform.cpp

diff --git a/src/gpu/GrColorSpaceXform.cpp b/src/gpu/GrColorSpaceXform.cpp
index 2d17610..3380b0f 100644
--- a/src/gpu/GrColorSpaceXform.cpp
+++ b/src/gpu/GrColorSpaceXform.cpp
@@ -58,3 +58,9 @@
 
     return sk_make_sp<GrColorSpaceXform>(srcToDst);
 }
+
+GrColor4f GrColorSpaceXform::apply(const GrColor4f& srcColor) {
+    GrColor4f result;
+    fSrcToDst.mapScalars(srcColor.fRGBA, result.fRGBA);
+    return result;
+}

src/gpu/GrDrawContext.cpp

diff --git a/src/gpu/GrDrawContext.cpp b/src/gpu/GrDrawContext.cpp
index 50965ba..e9a9619 100644
--- a/src/gpu/GrDrawContext.cpp
+++ b/src/gpu/GrDrawContext.cpp
@@ -86,12 +86,18 @@
     , fContext(context)
     , fInstancedPipelineInfo(fRenderTarget.get())
     , fColorSpace(std::move(colorSpace))
+    , fColorXformFromSRGB(nullptr)
     , fSurfaceProps(SkSurfacePropsCopyOrDefault(surfaceProps))
     , fAuditTrail(auditTrail)
 #ifdef SK_DEBUG
     , fSingleOwner(singleOwner)
 #endif
 {
+    if (fColorSpace) {
+        // sRGB sources are very common (SkColor, etc...), so we cache that gamut transformation
+        auto srgbColorSpace = SkColorSpace::NewNamed(SkColorSpace::kSRGB_Named);
+        fColorXformFromSRGB = GrColorSpaceXform::Make(srgbColorSpace.get(), fColorSpace.get());
+    }
     SkDEBUGCODE(this->validate();)
 }
 

src/gpu/SkGr.cpp

diff --git a/src/gpu/SkGr.cpp b/src/gpu/SkGr.cpp
index 7c0d09b..c8839f3 100644
--- a/src/gpu/SkGr.cpp
+++ b/src/gpu/SkGr.cpp
@@ -537,6 +537,10 @@
         origColor.fRGBA[0] = exact_srgb_to_linear(origColor.fRGBA[0]);
         origColor.fRGBA[1] = exact_srgb_to_linear(origColor.fRGBA[1]);
         origColor.fRGBA[2] = exact_srgb_to_linear(origColor.fRGBA[2]);
+
+        if (dc->getColorXformFromSRGB()) {
+            origColor = dc->getColorXformFromSRGB()->apply(origColor);
+        }
     }
 
     // Setup the initial color considering the shader, the SkPaint color, and the presence or not