Simplify gamma-correctness for text rendering.

src/gpu/text/GrAtlasTextContext.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "GrAtlasTextContext.h"
 
 #include "GrContext.h"
 #include "GrDrawContext.h"
@@ skipping 35 matching lines @@
         // gamma corrected masks anyways, nor color
         U8CPU lum = SkComputeLuminance(SkColorGetR(canonicalColor),
                                        SkColorGetG(canonicalColor),
                                        SkColorGetB(canonicalColor));
         // reduce to our finite number of bits
         canonicalColor = SkMaskGamma::CanonicalColor(SkColorSetRGB(lum, lum, lum));
     }
     return canonicalColor;
 }
 
-uint32_t GrAtlasTextContext::ComputeScalerContextFlags(GrDrawContext* dc, const GrPaint& grPaint) {
-    // If we're rendering to an sRGB render target, and we aren't forcing sRGB blending off,
-    // then we can disable the gamma hacks. Otherwise, leave them on. In either case, we still
-    // want the contrast boost:
-    if (GrPixelConfigIsSRGB(dc->accessRenderTarget()->config()) &&
-        !grPaint.getDisableOutputConversionToSRGB()) {
+uint32_t GrAtlasTextContext::ComputeScalerContextFlags(GrDrawContext* dc) {
+    // If we're doing gamma-correct rendering, then we can disable the gamma hacks.
+    // Otherwise, leave them on. In either case, we still want the contrast boost:
+    if (dc->isGammaCorrect()) {
         return SkPaint::kBoostContrast_ScalerContextFlag;
     } else {
         return SkPaint::kFakeGammaAndBoostContrast_ScalerContextFlags;
     }
 }
 
 // TODO if this function ever shows up in profiling, then we can compute this value when the
 // textblob is being built and cache it.  However, for the time being textblobs mostly only have 1
 // run so this is not a big deal to compute here.
 bool GrAtlasTextContext::HasLCD(const SkTextBlob* blob) {
@@ skipping 49 matching lines @@
         cacheBlob.reset(SkSafeRef(cache->find(key)));
     }
 
     // Though for the time being runs in the textblob can override the paint, they only touch font
     // info.
     GrPaint grPaint;
     if (!SkPaintToGrPaint(context, skPaint, viewMatrix, props.isGammaCorrect(), &grPaint)) {
         return;
     }
 
-    uint32_t scalerContextFlags = ComputeScalerContextFlags(dc, grPaint);
+    uint32_t scalerContextFlags = ComputeScalerContextFlags(dc);
 
     if (cacheBlob) {
         if (cacheBlob->mustRegenerate(skPaint, grPaint.getColor(), blurRec, viewMatrix, x, y)) {
             // We have to remake the blob because changes may invalidate our masks.
             // TODO we could probably get away reuse most of the time if the pointer is unique,
             // but we'd have to clear the subrun information
             cache->remove(cacheBlob);
             cacheBlob.reset(SkRef(cache->createCachedBlob(blob, key, blurRec, skPaint)));
             RegenerateTextBlob(cacheBlob, context->getBatchFontCache(),
                                *context->caps()->shaderCaps(), skPaint, grPaint.getColor(),
@@ skipping 180 matching lines @@
                                   const SkSurfaceProps& props,
                                   const char text[], size_t byteLength,
                                   SkScalar x, SkScalar y, const SkIRect& regionClipBounds) {
     if (context->abandoned()) {
         return;
     } else if (this->canDraw(skPaint, viewMatrix, props, *context->caps()->shaderCaps())) {
         SkAutoTUnref<GrAtlasTextBlob> blob(
             CreateDrawTextBlob(context->getTextBlobCache(), context->getBatchFontCache(),
                                *context->caps()->shaderCaps(),
                                paint, skPaint,
-                               ComputeScalerContextFlags(dc, paint),
+                               ComputeScalerContextFlags(dc),
                                viewMatrix, props,
                                text, byteLength, x, y));
         blob->flushThrowaway(context, dc, props, fDistanceAdjustTable, skPaint, paint,
                              clip, viewMatrix, regionClipBounds, x, y);
         return;
     }
 
     // fall back to drawing as a path
     GrTextUtils::DrawTextAsPath(context, dc, clip, skPaint, viewMatrix, text, byteLength, x, y,
                                 regionClipBounds);
 }
 
 void GrAtlasTextContext::drawPosText(GrContext* context,
                                      GrDrawContext* dc,
                                      const GrClip& clip,
                                      const GrPaint& paint, const SkPaint& skPaint,
                                      const SkMatrix& viewMatrix,
                                      const SkSurfaceProps& props,
                                      const char text[], size_t byteLength,
                                      const SkScalar pos[], int scalarsPerPosition,
                                      const SkPoint& offset, const SkIRect& regionClipBounds) {
     if (context->abandoned()) {
         return;
     } else if (this->canDraw(skPaint, viewMatrix, props, *context->caps()->shaderCaps())) {
         SkAutoTUnref<GrAtlasTextBlob> blob(
             CreateDrawPosTextBlob(context->getTextBlobCache(),
                                   context->getBatchFontCache(),
                                   *context->caps()->shaderCaps(),
                                   paint, skPaint,
-                                  ComputeScalerContextFlags(dc, paint),
+                                  ComputeScalerContextFlags(dc),
                                   viewMatrix, props,
                                   text, byteLength,
                                   pos, scalarsPerPosition,
                                   offset));
         blob->flushThrowaway(context, dc, props, fDistanceAdjustTable, skPaint, paint,
                              clip, viewMatrix, regionClipBounds, offset.fX, offset.fY);
         return;
     }
 
     // fall back to drawing as a path
@@ skipping 54 matching lines @@
                                                viewMatrix,
                                                gSurfaceProps, text,
                                                static_cast<size_t>(textLen), x, y));
 
     return blob->test_createBatch(textLen, 0, 0, viewMatrix, x, y, color, skPaint,
                                   gSurfaceProps, gTextContext->dfAdjustTable(),
                                   context->getBatchFontCache());
 }
 
 #endif