Fix to allow ovals GM to finish on N7

R=jvanverth@google.com, robertphillips@google.com

Author: bsalomon@google.com

Review URL: https://chromiumcodereview.appspot.com/23477079

git-svn-id: http://skia.googlecode.com/svn/trunk@11340 2bbb7eff-a529-9590-31e7-b0007b416f81

5 files changed, 44 insertions, 4 deletions

diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index 16a3640e29..be6fdb036d 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -980,9 +980,20 @@ void GrGLGradientEffect::emitColor(GrGLShaderBuilder* builder,
     } else if (GrGradientEffect::kThree_ColorType == ColorTypeFromKey(key)){
         builder->fsCodeAppendf("\tfloat oneMinus2t = 1.0 - (2.0 * (%s));\n",
                                gradientTValue);
-        builder->fsCodeAppendf("\tvec4 colorTemp = clamp(oneMinus2t, 0.0, 1.0) * %s +(1.0 - min(abs(oneMinus2t), 1.0)) * %s + clamp(-oneMinus2t, 0.0, 1.0) * %s;\n",
-                               builder->getUniformVariable(fColorStartUni).c_str(),
-                               builder->getUniformVariable(fColorMidUni).c_str(),
+        builder->fsCodeAppendf("\tvec4 colorTemp = clamp(oneMinus2t, 0.0, 1.0) * %s;\n",
+                               builder->getUniformVariable(fColorStartUni).c_str());
+        if (kTegra3_GrGLRenderer == builder->ctxInfo().renderer()) {
+            // The Tegra3 compiler will sometimes never return if we have
+            // min(abs(oneMinus2t), 1.0), or do the abs first in a separate expression.
+            builder->fsCodeAppend("\tfloat minAbs = abs(oneMinus2t);\n");
+            builder->fsCodeAppend("\tminAbs = minAbs > 1.0 ? 1.0 : minAbs;\n");
+            builder->fsCodeAppendf("\tcolorTemp += (1.0 - minAbs) * %s;\n",
+                                   builder->getUniformVariable(fColorMidUni).c_str());
+        } else {
+            builder->fsCodeAppendf("\tcolorTemp += (1.0 - min(abs(oneMinus2t), 1.0)) * %s;\n",
+                                   builder->getUniformVariable(fColorMidUni).c_str());
+        }
+        builder->fsCodeAppendf("\tcolorTemp += clamp(-oneMinus2t, 0.0, 1.0) * %s;\n",
                                builder->getUniformVariable(fColorEndUni).c_str());
         if (GrGradientEffect::kAfterInterp_PremulType == PremulTypeFromKey(key)) {
             builder->fsCodeAppend("\tcolorTemp.rgb *= colorTemp.a;\n");
diff --git a/src/gpu/gl/GrGLContext.cpp b/src/gpu/gl/GrGLContext.cpp
index 93f369109a..097fce23e2 100644
--- a/src/gpu/gl/GrGLContext.cpp
+++ b/src/gpu/gl/GrGLContext.cpp
@@ -13,6 +13,7 @@ GrGLContextInfo& GrGLContextInfo::operator= (const GrGLContextInfo& ctxInfo) {
     fGLVersion = ctxInfo.fGLVersion;
     fGLSLGeneration = ctxInfo.fGLSLGeneration;
     fVendor = ctxInfo.fVendor;
+    fRenderer = ctxInfo.fRenderer;
     fExtensions = ctxInfo.fExtensions;
     fIsMesa = ctxInfo.fIsMesa;
     *fGLCaps = *ctxInfo.fGLCaps.get();
@@ -38,6 +39,8 @@ bool GrGLContextInfo::initialize(const GrGLInterface* interface) {
 
             fVendor = GrGLGetVendor(interface);
 
+            fRenderer = GrGLGetRenderer(interface);
+
             fIsMesa = GrGLIsMesaFromVersionString(ver);
 
             fGLCaps->init(*this, interface);
@@ -56,6 +59,7 @@ void GrGLContextInfo::reset() {
     fGLVersion = GR_GL_VER(0, 0);
     fGLSLGeneration = static_cast<GrGLSLGeneration>(0);
     fVendor = kOther_GrGLVendor;
+    fRenderer = kOther_GrGLRenderer;
     fIsMesa = false;
     fExtensions.reset();
     fGLCaps->reset();
diff --git a/src/gpu/gl/GrGLContext.h b/src/gpu/gl/GrGLContext.h
index ac9e9ed900..b6e1ab3942 100644
--- a/src/gpu/gl/GrGLContext.h
+++ b/src/gpu/gl/GrGLContext.h
@@ -47,6 +47,7 @@ public:
     GrGLVersion version() const { return fGLVersion; }
     GrGLSLGeneration glslGeneration() const { return fGLSLGeneration; }
     GrGLVendor vendor() const { return fVendor; }
+    GrGLRenderer renderer() const { return fRenderer; }
     /** Is this a mesa-based driver. Does not mean it is the osmesa software rasterizer. */
     bool isMesa() const { return fIsMesa; }
     const GrGLCaps* caps() const { return fGLCaps.get(); }
@@ -74,6 +75,7 @@ private:
     GrGLVersion             fGLVersion;
     GrGLSLGeneration        fGLSLGeneration;
     GrGLVendor              fVendor;
+    GrGLRenderer            fRenderer;
     GrGLExtensions          fExtensions;
     bool                    fIsMesa;
     SkAutoTUnref<GrGLCaps>  fGLCaps;
diff --git a/src/gpu/gl/GrGLUtil.cpp b/src/gpu/gl/GrGLUtil.cpp
index d6f5820781..0e3d2a3f7b 100644
--- a/src/gpu/gl/GrGLUtil.cpp
+++ b/src/gpu/gl/GrGLUtil.cpp
@@ -214,6 +214,15 @@ GrGLVendor GrGLGetVendorFromString(const char* vendorString) {
     return kOther_GrGLVendor;
 }
 
+GrGLRenderer GrGLGetRendererFromString(const char* rendererString) {
+    if (NULL != rendererString) {
+        if (0 == strcmp(rendererString, "NVIDIA Tegra 3")) {
+            return kTegra3_GrGLRenderer;
+        }
+    }
+    return kOther_GrGLRenderer;
+}
+
 GrGLBinding GrGLGetBindingInUse(const GrGLInterface* gl) {
     const GrGLubyte* v;
     GR_GL_CALL_RET(gl, v, GetString(GR_GL_VERSION));
@@ -238,6 +247,12 @@ GrGLVendor GrGLGetVendor(const GrGLInterface* gl) {
     return GrGLGetVendorFromString((const char*) v);
 }
 
+GrGLRenderer GrGLGetRenderer(const GrGLInterface* gl) {
+    const GrGLubyte* v;
+    GR_GL_CALL_RET(gl, v, GetString(GR_GL_RENDERER));
+    return GrGLGetRendererFromString((const char*) v);
+}
+
 template<> void GrGLGetMatrix<3>(GrGLfloat* dest, const SkMatrix& src) {
     // Col 0
     dest[0] = SkScalarToFloat(src[SkMatrix::kMScaleX]);
diff --git a/src/gpu/gl/GrGLUtil.h b/src/gpu/gl/GrGLUtil.h
index 686943bdce..5bcf2f324c 100644
--- a/src/gpu/gl/GrGLUtil.h
+++ b/src/gpu/gl/GrGLUtil.h
@@ -19,7 +19,7 @@ typedef uint32_t GrGLVersion;
 typedef uint32_t GrGLSLVersion;
 
 /**
- * This list is lazily updated as required.
+ * The Vendor and Renderer enum values are lazily updated as required.
  */
 enum GrGLVendor {
     kARM_GrGLVendor,
@@ -30,6 +30,12 @@ enum GrGLVendor {
     kOther_GrGLVendor
 };
 
+enum GrGLRenderer {
+    kTegra3_GrGLRenderer,
+
+    kOther_GrGLRenderer
+};
+
 #define GR_GL_VER(major, minor) ((static_cast<int>(major) << 16) | \
                                  static_cast<int>(minor))
 #define GR_GLSL_VER(major, minor) ((static_cast<int>(major) << 16) | \
@@ -76,12 +82,14 @@ GrGLBinding GrGLGetBindingInUseFromString(const char* versionString);
 GrGLSLVersion GrGLGetGLSLVersionFromString(const char* versionString);
 bool GrGLIsMesaFromVersionString(const char* versionString);
 GrGLVendor GrGLGetVendorFromString(const char* vendorString);
+GrGLRenderer GrGLGetRendererFromString(const char* rendererString);
 
 // these variants call glGetString()
 GrGLBinding GrGLGetBindingInUse(const GrGLInterface*);
 GrGLVersion GrGLGetVersion(const GrGLInterface*);
 GrGLSLVersion GrGLGetGLSLVersion(const GrGLInterface*);
 GrGLVendor GrGLGetVendor(const GrGLInterface*);
+GrGLRenderer GrGLGetRenderer(const GrGLInterface*);
 
 /**
  * Helpers for glGetError()