Require sRGB write control for sRGB support. Add flag to GrPaint to suppress linear -> sRGB conversion on write. Use that to fix YUV conversion, which directly produces sRGB data. (Technically, it produces data in whatever the color space of the JPEG might be).

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1830303002

Review URL: https://codereview.chromium.org/1830303002

2 files changed, 16 insertions, 0 deletions

diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 1f5b11955b..398517cb68 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -137,6 +137,13 @@ public:
     /** To avoid as-yet-unnecessary complexity we don't allow any partial support of MIP Maps (e.g.
         only for POT textures) */
     bool mipMapSupport() const { return fMipMapSupport; }
+
+    /**
+     * Skia convention is that a device only has sRGB support if it supports sRGB formats for both
+     * textures and framebuffers. In addition:
+     *   Decoding to linear of an sRGB texture can be disabled.
+     *   Encoding and gamma-correct blending to an sRGB framebuffer can be disabled.
+     */
     bool srgbSupport() const { return fSRGBSupport; }
     bool twoSidedStencilSupport() const { return fTwoSidedStencilSupport; }
     bool stencilWrapOpsSupport() const { return  fStencilWrapOpsSupport; }
diff --git a/include/gpu/GrPaint.h b/include/gpu/GrPaint.h
index 152cb51d7e..3f06f092ab 100644
--- a/include/gpu/GrPaint.h
+++ b/include/gpu/GrPaint.h
@@ -56,6 +56,13 @@ public:
     void setAntiAlias(bool aa) { fAntiAlias = aa; }
     bool isAntiAlias() const { return fAntiAlias; }
 
+    /**
+     * Should shader output conversion from linear to sRGB be disabled.
+     * Only relevant if the destination is sRGB. Defaults to false.
+     */
+    void setDisableOutputConversionToSRGB(bool srgb) { fDisableOutputConversionToSRGB = srgb; }
+    bool getDisableOutputConversionToSRGB() const { return fDisableOutputConversionToSRGB; }
+
     const GrXPFactory* setXPFactory(const GrXPFactory* xpFactory) {
         fXPFactory.reset(SkSafeRef(xpFactory));
         return xpFactory;
@@ -112,6 +119,7 @@ public:
 
     GrPaint& operator=(const GrPaint& paint) {
         fAntiAlias = paint.fAntiAlias;
+        fDisableOutputConversionToSRGB = paint.fDisableOutputConversionToSRGB;
 
         fColor = paint.fColor;
         this->resetFragmentProcessors();
@@ -154,6 +162,7 @@ private:
     SkSTArray<2, const GrFragmentProcessor*, true>  fCoverageFragmentProcessors;
 
     bool                                            fAntiAlias;
+    bool                                            fDisableOutputConversionToSRGB;
 
     GrColor                                         fColor;
 };