Infer sampler precision from pixel config

include/gpu/GrTypesPriv.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrTypesPriv_DEFINED
 #define GrTypesPriv_DEFINED
 
@@ skipping 53 matching lines @@
 
     // Default precision is medium. This is because on OpenGL ES 2 highp support is not
     // guaranteed. On (non-ES) OpenGL the specifiers have no effect on precision.
     kDefault_GrSLPrecision = kMedium_GrSLPrecision,
 
     kLast_GrSLPrecision = kHigh_GrSLPrecision
 };
 
 static const int kGrSLPrecisionCount = kLast_GrSLPrecision + 1;
 
+static inline GrSLPrecision GrPixelConfigPrecision(GrPixelConfig config) {
+    static const GrSLPrecision precisions[] = {
+        kLow_GrSLPrecision,       // kUnknown_GrPixelConfig
+        kLow_GrSLPrecision,       // kAlpha_8_GrPixelConfig
+        kLow_GrSLPrecision,       // kIndex_8_GrPixelConfig
+        kLow_GrSLPrecision,       // kRGB_565_GrPixelConfig
+        kLow_GrSLPrecision,       // kRGBA_4444_GrPixelConfig
+        kLow_GrSLPrecision,       // kRGBA_8888_GrPixelConfig
+        kLow_GrSLPrecision,       // kBGRA_8888_GrPixelConfig
+        kLow_GrSLPrecision,       // kSRGBA_8888_GrPixelConfig
+        kLow_GrSLPrecision,       // kSBGRA_8888_GrPixelConfig
+        kLow_GrSLPrecision,       // kETC1_GrPixelConfig
+        kLow_GrSLPrecision,       // kLATC_GrPixelConfig
+        kLow_GrSLPrecision,       // kR11_EAC_GrPixelConfig
+        kLow_GrSLPrecision,       // kASTC_12x12_GrPixelConfig
+        kHigh_GrSLPrecision,      // kRGBA_float_GrPixelConfig
+        kMedium_GrSLPrecision,    // kAlpha_half_GrPixelConfig
+        kMedium_GrSLPrecision,    // kRGBA_half_GrPixelConfig
+    };
+
+    SkASSERT(config >= 0 && config <= kLast_GrPixelConfig);
+    return precisions[config];
+
+    GR_STATIC_ASSERT(0 == kUnknown_GrPixelConfig);
+    GR_STATIC_ASSERT(1 == kAlpha_8_GrPixelConfig);
+    GR_STATIC_ASSERT(2 == kIndex_8_GrPixelConfig);
+    GR_STATIC_ASSERT(3 == kRGB_565_GrPixelConfig);
+    GR_STATIC_ASSERT(4 == kRGBA_4444_GrPixelConfig);
+    GR_STATIC_ASSERT(5 == kRGBA_8888_GrPixelConfig);
+    GR_STATIC_ASSERT(6 == kBGRA_8888_GrPixelConfig);
+    GR_STATIC_ASSERT(7 == kSRGBA_8888_GrPixelConfig);
+    GR_STATIC_ASSERT(8 == kSBGRA_8888_GrPixelConfig);
+    GR_STATIC_ASSERT(9 == kETC1_GrPixelConfig);
+    GR_STATIC_ASSERT(10 == kLATC_GrPixelConfig);
+    GR_STATIC_ASSERT(11 == kR11_EAC_GrPixelConfig);
+    GR_STATIC_ASSERT(12 == kASTC_12x12_GrPixelConfig);
+    GR_STATIC_ASSERT(13 == kRGBA_float_GrPixelConfig);
+    GR_STATIC_ASSERT(14 == kAlpha_half_GrPixelConfig);
+    GR_STATIC_ASSERT(15 == kRGBA_half_GrPixelConfig);
+    GR_STATIC_ASSERT(SK_ARRAY_COUNT(precisions) == kGrPixelConfigCnt);
+}
+
 /**
  * Gets the vector size of the SLType. Returns -1 for void, matrices, and samplers.
  */
 static inline int GrSLTypeVectorCount(GrSLType type) {
     SkASSERT(type >= 0 && type < static_cast<GrSLType>(kGrSLTypeCount));
     static const int kCounts[] = { -1, 1, 2, 3, 4, -1, -1, -1, -1, -1, -1, 1, 1, 1 };
     return kCounts[type];
 
     GR_STATIC_ASSERT(0 == kVoid_GrSLType);
     GR_STATIC_ASSERT(1 == kFloat_GrSLType);
@@ skipping 358 matching lines @@
 // Takes a pointer to a GrCaps, and will suppress prints if required
 #define GrCapsDebugf(caps, ...)         \
     if (!caps->suppressPrints()) {      \
         SkDebugf(__VA_ARGS__);          \
     }
 #else
 #define GrCapsDebugf(caps, ...)
 #endif
 
 #endif