From 5105d68f93e9c294d9cfa56247ca2119ec8da8d4 Mon Sep 17 00:00:00 2001
From: Brian Osman <brianosman@google.com>
Date: Wed, 13 Feb 2019 16:06:14 -0500
Subject: [PATCH] Use half-floats for out-of-gamut color in GrAAFillRRectOp

Bug: skia:
Change-Id: Id093f295708b1f6719bece9899ebadfb9a473e46
Reviewed-on: https://skia-review.googlesource.com/c/192101
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Chris Dalton <csmartdalton@google.com>
---
 src/gpu/ops/GrAAFillRRectOp.cpp | 39 +++++++++++++++++++++------------
 src/gpu/ops/GrAAFillRRectOp.h   |  3 ++-
 2 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/src/gpu/ops/GrAAFillRRectOp.cpp b/src/gpu/ops/GrAAFillRRectOp.cpp
index 17c71f6b36..c38e6d3025 100644
--- a/src/gpu/ops/GrAAFillRRectOp.cpp
+++ b/src/gpu/ops/GrAAFillRRectOp.cpp
@@ -90,8 +90,16 @@ GrProcessorSet::Analysis GrAAFillRRectOp::finalize(const GrCaps& caps, const GrA
             &overrideColor);
 
     // Finish writing the instance attribs.
-    this->writeInstanceData(
-            (analysis.inputColorIsOverridden() ? overrideColor : fOriginalColor).toBytes_RGBA());
+    SkPMColor4f finalColor = analysis.inputColorIsOverridden() ? overrideColor : fOriginalColor;
+    if (!SkPMColor4fFitsInBytes(finalColor)) {
+        fFlags |= Flags::kWideColor;
+        uint32_t halfColor[2];
+        SkFloatToHalf_finite_ftz(Sk4f::Load(finalColor.vec())).store(&halfColor);
+        this->writeInstanceData(halfColor[0], halfColor[1]);
+    } else {
+        this->writeInstanceData(finalColor.toBytes_RGBA());
+    }
+
     if (analysis.usesLocalCoords()) {
         this->writeInstanceData(fLocalRect);
         fFlags |= Flags::kHasLocalCoords;
@@ -260,7 +268,14 @@ public:
             : GrGeometryProcessor(kGrAAFillRRectOp_Processor_ClassID)
             , fFlags(flags) {
         this->setVertexAttributes(kVertexAttribs, 3);
-        this->setInstanceAttributes(kInstanceAttribs, (flags & Flags::kHasLocalCoords) ? 6 : 5);
+        fInSkew = { "skew", kFloat4_GrVertexAttribType, kFloat4_GrSLType };
+        fInTranslate = { "translate", kFloat2_GrVertexAttribType, kFloat2_GrSLType };
+        fInRadiiX = { "radii_x", kFloat4_GrVertexAttribType, kFloat4_GrSLType };
+        fInRadiiY = { "radii_y", kFloat4_GrVertexAttribType, kFloat4_GrSLType };
+        fInColor = MakeColorAttribute("color", (flags & Flags::kWideColor));
+        fInLocalRect = {"local_rect", kFloat4_GrVertexAttribType, kFloat4_GrSLType};
+
+        this->setInstanceAttributes(&fInSkew, (flags & Flags::kHasLocalCoords) ? 6 : 5);
         SkASSERT(this->vertexStride() == sizeof(Vertex));
     }
 
@@ -278,15 +293,12 @@ private:
             {"corner_and_radius_outsets", kFloat4_GrVertexAttribType, kFloat4_GrSLType},
             {"aa_bloat_and_coverage", kFloat4_GrVertexAttribType, kFloat4_GrSLType}};
 
-    static constexpr Attribute kInstanceAttribs[] = {
-            {"skew", kFloat4_GrVertexAttribType, kFloat4_GrSLType},
-            {"translate", kFloat2_GrVertexAttribType, kFloat2_GrSLType},
-            {"radii_x", kFloat4_GrVertexAttribType, kFloat4_GrSLType},
-            {"radii_y", kFloat4_GrVertexAttribType, kFloat4_GrSLType},
-            {"color", kUByte4_norm_GrVertexAttribType, kHalf4_GrSLType},
-            {"local_rect", kFloat4_GrVertexAttribType, kFloat4_GrSLType}};  // Conditional.
-
-    static constexpr int kColorAttribIdx = 4;
+    Attribute fInSkew;
+    Attribute fInTranslate;
+    Attribute fInRadiiX;
+    Attribute fInRadiiY;
+    Attribute fInColor;
+    Attribute fInLocalRect;  // Conditional.
 
     const Flags fFlags;
 
@@ -294,7 +306,6 @@ private:
 };
 
 constexpr GrPrimitiveProcessor::Attribute GrAAFillRRectOp::Processor::kVertexAttribs[];
-constexpr GrPrimitiveProcessor::Attribute GrAAFillRRectOp::Processor::kInstanceAttribs[];
 
 class GrAAFillRRectOp::Processor::Impl : public GrGLSLGeometryProcessor {
 public:
@@ -304,7 +315,7 @@ public:
 
         GrGLSLVaryingHandler* varyings = args.fVaryingHandler;
         varyings->emitAttributes(proc);
-        varyings->addPassThroughAttribute(proc.kInstanceAttribs[kColorAttribIdx], args.fOutputColor,
+        varyings->addPassThroughAttribute(proc.fInColor, args.fOutputColor,
                                           GrGLSLVaryingHandler::Interpolation::kCanBeFlat);
 
         // Emit the vertex shader.
diff --git a/src/gpu/ops/GrAAFillRRectOp.h b/src/gpu/ops/GrAAFillRRectOp.h
index 95993fa939..7129583e61 100644
--- a/src/gpu/ops/GrAAFillRRectOp.h
+++ b/src/gpu/ops/GrAAFillRRectOp.h
@@ -34,7 +34,8 @@ private:
     enum class Flags {
         kNone = 0,
         kUseHWDerivatives = 1 << 0,
-        kHasLocalCoords = 1 << 1
+        kHasLocalCoords = 1 << 1,
+        kWideColor = 1 << 2
     };
 
     GR_DECL_BITFIELD_CLASS_OPS_FRIENDS(Flags);