Distance field fixes for Android

src/gpu/gl/GrGLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLCaps.h"
 #include "GrGLContext.h"
@@ skipping 29 matching lines @@
     fTextureRedSupport = false;
     fImagingSupport = false;
     fTwoFormatLimit = false;
     fFragCoordsConventionSupport = false;
     fVertexArrayObjectSupport = false;
     fUseNonVBOVertexAndIndexDynamicData = false;
     fIsCoreProfile = false;
     fFixedFunctionSupport = false;
     fDiscardFBSupport = false;
     fFullClearIsFree = false;
+    fDropsTileOnZeroDivide = false;
 }
 
 GrGLCaps::GrGLCaps(const GrGLCaps& caps) : GrDrawTargetCaps() {
     *this = caps;
 }
 
 GrGLCaps& GrGLCaps::operator = (const GrGLCaps& caps) {
     INHERITED::operator=(caps);
     fVerifiedColorConfigs = caps.fVerifiedColorConfigs;
     fStencilFormats = caps.fStencilFormats;
@@ skipping 17 matching lines @@
     fTextureRedSupport = caps.fTextureRedSupport;
     fImagingSupport = caps.fImagingSupport;
     fTwoFormatLimit = caps.fTwoFormatLimit;
     fFragCoordsConventionSupport = caps.fFragCoordsConventionSupport;
     fVertexArrayObjectSupport = caps.fVertexArrayObjectSupport;
     fUseNonVBOVertexAndIndexDynamicData = caps.fUseNonVBOVertexAndIndexDynamicData;
     fIsCoreProfile = caps.fIsCoreProfile;
     fFixedFunctionSupport = caps.fFixedFunctionSupport;
     fDiscardFBSupport = caps.fDiscardFBSupport;
     fFullClearIsFree = caps.fFullClearIsFree;
+    fDropsTileOnZeroDivide = caps.fDropsTileOnZeroDivide;
 
     return *this;
 }
 
 void GrGLCaps::init(const GrGLContextInfo& ctxInfo, const GrGLInterface* gli) {
 
     this->reset();
     if (!ctxInfo.isInitialized()) {
         return;
     }
@@ skipping 140 matching lines @@
     }
 
     if (kGLES_GrGLStandard == standard) {
         if (ctxInfo.hasExtension("GL_EXT_shader_framebuffer_fetch")) {
             fFBFetchType = kEXT_FBFetchType;
         } else if (ctxInfo.hasExtension("GL_NV_shader_framebuffer_fetch")) {
             fFBFetchType = kNV_FBFetchType;
         }
     }
 
+    // Adreno GPUs have a tendency to drop tiles when there is a divide-by-zero in a shader
+    fDropsTileOnZeroDivide = kQualcomm_GrGLVendor == ctxInfo.vendor();
+
     this->initFSAASupport(ctxInfo, gli);
     this->initStencilFormats(ctxInfo);
 
     /**************************************************************************
      * GrDrawTargetCaps fields
      **************************************************************************/
     GrGLint numFormats;
     GR_GL_GetIntegerv(gli, GR_GL_NUM_COMPRESSED_TEXTURE_FORMATS, &numFormats);
     if (numFormats) {
         SkAutoSTMalloc<10, GrGLint> formats(numFormats);
@@ skipping 397 matching lines @@
     r.appendf("GL_R support: %s\n", (fTextureRedSupport ? "YES": "NO"));
     r.appendf("GL_ARB_imaging support: %s\n", (fImagingSupport ? "YES": "NO"));
     r.appendf("Two Format Limit: %s\n", (fTwoFormatLimit ? "YES": "NO"));
     r.appendf("Fragment coord conventions support: %s\n",
              (fFragCoordsConventionSupport ? "YES": "NO"));
     r.appendf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     r.appendf("Use non-VBO for dynamic data: %s\n",
              (fUseNonVBOVertexAndIndexDynamicData ? "YES" : "NO"));
     r.appendf("Discard FrameBuffer support: %s\n", (fDiscardFBSupport ? "YES" : "NO"));
     r.appendf("Full screen clear is free: %s\n", (fFullClearIsFree ? "YES" : "NO"));
+    r.appendf("Drops tile on zero divide: %s\n", (fDropsTileOnZeroDivide ? "YES" : "NO"));
     return r;
 }