Reland "Fix precision caps and rrect/ellipse effect precisions"

This is a reland of e42180022720f2fcfd3c634cad855506a7940591
Original change's description:
> Fix precision caps and rrect/ellipse effect precisions
>
> Replaces all the complex precision caps with a single flag that says
> whether "float" == fp32. Updates the ellipse and rrect effects to
> use float coords, and use the scale workaround when float != fp32.
>
> Bug: skia:7190
> Change-Id: Ieccff9f38acd05e5cec78fe90d01a5da901a9307
> Reviewed-on: https://skia-review.googlesource.com/70961
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com

Bug: skia:7190
Change-Id: I7ced37a64164b83d86f6a957c35e10ce9085aba0
Reviewed-on: https://skia-review.googlesource.com/72760
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>

1 files changed, 4 insertions, 100 deletions

diff --git a/src/gpu/GrShaderCaps.cpp b/src/gpu/GrShaderCaps.cpp
index 124fd4de40..2d9cd0a39b 100644
--- a/src/gpu/GrShaderCaps.cpp
+++ b/src/gpu/GrShaderCaps.cpp
@@ -13,32 +13,6 @@
 
 ////////////////////////////////////////////////////////////////////////////////////////////
 
-static const char* shader_type_to_string(GrShaderType type) {
-    switch (type) {
-    case kVertex_GrShaderType:
-        return "vertex";
-    case kGeometry_GrShaderType:
-        return "geometry";
-    case kFragment_GrShaderType:
-        return "fragment";
-    }
-    return "";
-}
-
-static const char* precision_to_string(GrSLPrecision p) {
-    switch (p) {
-    case kLow_GrSLPrecision:
-        return "low";
-    case kMedium_GrSLPrecision:
-        return "medium";
-    case kHigh_GrSLPrecision:
-        return "high";
-    default:
-        SK_ABORT("Unexpected precision type.");
-        return "";
-    }
-}
-
 GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
     fGLSLGeneration = k330_GrGLSLGeneration;
     fShaderDerivativeSupport = false;
@@ -50,7 +24,6 @@ GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
     fIntegerSupport = false;
     fTexelBufferSupport = false;
     fImageLoadStoreSupport = false;
-    fShaderPrecisionVaries = false;
     fDropsTileOnZeroDivide = false;
     fFBFetchSupport = false;
     fFBFetchNeedsCustomOutput = false;
@@ -73,6 +46,8 @@ GrShaderCaps::GrShaderCaps(const GrContextOptions& options) {
     fExternalTextureSupport = false;
     fTexelFetchSupport = false;
     fVertexIDSupport = false;
+    fFloatIs32Bits = true;
+    fHalfIs32Bits = false;
 
     fVersionDeclString = nullptr;
     fShaderDerivativeExtensionString = nullptr;
@@ -113,26 +88,6 @@ void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
     writer->appendBool("Texel Buffer Support", fTexelBufferSupport);
     writer->appendBool("Image Load Store Support", fImageLoadStoreSupport);
 
-    writer->appendBool("Variable Precision", fShaderPrecisionVaries);
-
-    for (int s = 0; s < kGrShaderTypeCount; ++s) {
-        GrShaderType shaderType = static_cast<GrShaderType>(s);
-        writer->beginArray(SkStringPrintf("%s precisions",
-                                          shader_type_to_string(shaderType)).c_str());
-        for (int p = 0; p < kGrSLPrecisionCount; ++p) {
-            if (fFloatPrecisions[s][p].supported()) {
-                GrSLPrecision precision = static_cast<GrSLPrecision>(p);
-                writer->beginObject(nullptr, false);
-                writer->appendString("precision", precision_to_string(precision));
-                writer->appendS32("log_low", fFloatPrecisions[s][p].fLogRangeLow);
-                writer->appendS32("log_high", fFloatPrecisions[s][p].fLogRangeHigh);
-                writer->appendS32("bits", fFloatPrecisions[s][p].fBits);
-                writer->endObject();
-            }
-        }
-        writer->endArray();
-    }
-
     static const char* kAdvBlendEqInteractionStr[] = {
         "Not Supported",
         "Automatic",
@@ -166,6 +121,8 @@ void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
     writer->appendBool("External texture support", fExternalTextureSupport);
     writer->appendBool("texelFetch support", fTexelFetchSupport);
     writer->appendBool("sk_VertexID support", fVertexIDSupport);
+    writer->appendBool("float == fp32", fFloatIs32Bits);
+    writer->appendBool("half == fp32", fHalfIs32Bits);
 
     writer->appendS32("Max VS Samplers", fMaxVertexSamplers);
     writer->appendS32("Max GS Samplers", fMaxGeometrySamplers);
@@ -178,59 +135,6 @@ void GrShaderCaps::dumpJSON(SkJSONWriter* writer) const {
     writer->endObject();
 }
 
-void GrShaderCaps::initSamplerPrecisionTable() {
-    // Determine the largest precision qualifiers that are effectively the same as lowp/mediump.
-    //   e.g. if lowp == mediump, then use mediump instead of lowp.
-    GrSLPrecision effectiveMediumP[kGrShaderTypeCount];
-    GrSLPrecision effectiveLowP[kGrShaderTypeCount];
-    for (int s = 0; s < kGrShaderTypeCount; ++s) {
-        const PrecisionInfo* info = fFloatPrecisions[s];
-        effectiveMediumP[s] = info[kHigh_GrSLPrecision] == info[kMedium_GrSLPrecision] ?
-                                  kHigh_GrSLPrecision : kMedium_GrSLPrecision;
-        effectiveLowP[s] = info[kMedium_GrSLPrecision] == info[kLow_GrSLPrecision] ?
-                               effectiveMediumP[s] : kLow_GrSLPrecision;
-    }
-
-    // Determine which precision qualifiers should be used with samplers.
-    for (int visibility = 0; visibility < (1 << kGrShaderTypeCount); ++visibility) {
-        GrSLPrecision mediump = kHigh_GrSLPrecision;
-        GrSLPrecision lowp = kHigh_GrSLPrecision;
-        for (int s = 0; s < kGrShaderTypeCount; ++s) {
-            if (visibility & (1 << s)) {
-                mediump = SkTMin(mediump, effectiveMediumP[s]);
-                lowp = SkTMin(lowp, effectiveLowP[s]);
-            }
-
-            GR_STATIC_ASSERT(0 == kLow_GrSLPrecision);
-            GR_STATIC_ASSERT(1 == kMedium_GrSLPrecision);
-            GR_STATIC_ASSERT(2 == kHigh_GrSLPrecision);
-
-            GR_STATIC_ASSERT((1 << kVertex_GrShaderType) == kVertex_GrShaderFlag);
-            GR_STATIC_ASSERT((1 << kGeometry_GrShaderType) == kGeometry_GrShaderFlag);
-            GR_STATIC_ASSERT((1 << kFragment_GrShaderType) == kFragment_GrShaderFlag);
-            GR_STATIC_ASSERT(3 == kGrShaderTypeCount);
-        }
-
-        uint8_t* table = fSamplerPrecisions[visibility];
-        table[kUnknown_GrPixelConfig]        = lowp;
-        table[kAlpha_8_GrPixelConfig]        = lowp;
-        table[kGray_8_GrPixelConfig]         = lowp;
-        table[kRGB_565_GrPixelConfig]        = lowp;
-        table[kRGBA_4444_GrPixelConfig]      = lowp;
-        table[kRGBA_8888_GrPixelConfig]      = lowp;
-        table[kBGRA_8888_GrPixelConfig]      = lowp;
-        table[kSRGBA_8888_GrPixelConfig]     = lowp;
-        table[kSBGRA_8888_GrPixelConfig]     = lowp;
-        table[kRGBA_8888_sint_GrPixelConfig] = lowp;
-        table[kRGBA_float_GrPixelConfig]     = kHigh_GrSLPrecision;
-        table[kRG_float_GrPixelConfig]       = kHigh_GrSLPrecision;
-        table[kAlpha_half_GrPixelConfig]     = mediump;
-        table[kRGBA_half_GrPixelConfig]      = mediump;
-
-        GR_STATIC_ASSERT(14 == kGrPixelConfigCnt);
-    }
-}
-
 void GrShaderCaps::applyOptionsOverrides(const GrContextOptions& options) {
 #if GR_TEST_UTILS
     fDualSourceBlendingSupport = fDualSourceBlendingSupport && !options.fSuppressDualSourceBlending;