commit 7023a00c35d904e4ccff09c377e9ba26abba6181
author jvanverth <jvanverth@google.com> Mon Feb 22 11:25:32 2016 -0800
committer Commit bot <commit-bot@chromium.org> Mon Feb 22 11:25:32 2016 -0800
tree 33a9241b646576bd5c66b88623c1db8d925d1274
parent 01e583807618038a578a3b07cfad3101d24115c7

Use unorm shorts for texture coordinates when rendering text.

There are a couple of reasons for this:
- Vulkan does not guarantee conversions from integral vertex attributes
  to floating point shader variables
- This may be faster and more precise on some platforms, as it avoids
  the aforementioned conversion and changes a multiply by a very small
  value to a multiply by a medium-sized value.
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1713693002
TBR=bsalomon@google.com

Committed: https://skia.googlesource.com/skia/+/e507ff0460f4f878214b9454fb5b9ab8d64d8063

Review URL: https://codereview.chromium.org/1713693002

src/gpu/effects/GrBitmapTextGeoProc.cpp

diff --git a/src/gpu/effects/GrBitmapTextGeoProc.cpp b/src/gpu/effects/GrBitmapTextGeoProc.cpp
index 263676d..18f12bd 100644
--- a/src/gpu/effects/GrBitmapTextGeoProc.cpp
+++ b/src/gpu/effects/GrBitmapTextGeoProc.cpp
@@ -31,16 +31,12 @@
 
         // compute numbers to be hardcoded to convert texture coordinates from int to float
         SkASSERT(cte.numTextures() == 1);
-        GrTexture* atlas = cte.textureAccess(0).getTexture();
+        SkDEBUGCODE(GrTexture* atlas = cte.textureAccess(0).getTexture());
         SkASSERT(atlas && SkIsPow2(atlas->width()) && SkIsPow2(atlas->height()));
-        SkScalar recipWidth = 1.0f / atlas->width();
-        SkScalar recipHeight = 1.0f / atlas->height();
 
         GrGLSLVertToFrag v(kVec2f_GrSLType);
-        varyingHandler->addVarying("TextureCoords", &v);
-        vertBuilder->codeAppendf("%s = vec2(%.*f, %.*f) * %s;", v.vsOut(),
-                                 GR_SIGNIFICANT_POW2_DECIMAL_DIG, recipWidth,
-                                 GR_SIGNIFICANT_POW2_DECIMAL_DIG, recipHeight,
+        varyingHandler->addVarying("TextureCoords", &v, kHigh_GrSLPrecision);
+        vertBuilder->codeAppendf("%s = %s;", v.vsOut(),
                                  cte.inTextureCoords()->fName);
 
         GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
@@ -150,7 +146,8 @@
         fInColor = &this->addVertexAttrib(Attribute("inColor", kVec4ub_GrVertexAttribType));
     }
     fInTextureCoords = &this->addVertexAttrib(Attribute("inTextureCoords",
-                                                        kVec2s_GrVertexAttribType));
+                                                        kVec2us_GrVertexAttribType,
+                                                        kHigh_GrSLPrecision));
     this->addTextureAccess(&fTextureAccess);
 }