Fully remove coord transform precision code

Coord transforms are always computed and interpolated at high precision.

Bug: skia:
Change-Id: I5f7eadc2080df8ad5cbb080835c0dba09c59e63e
Reviewed-on: https://skia-review.googlesource.com/11180
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>

9 files changed, 33 insertions, 107 deletions

diff --git a/include/gpu/GrCoordTransform.h b/include/gpu/GrCoordTransform.h
index 5725a69433..54c21b7472 100644
--- a/include/gpu/GrCoordTransform.h
+++ b/include/gpu/GrCoordTransform.h
@@ -8,12 +8,10 @@
 #ifndef GrCoordTransform_DEFINED
 #define GrCoordTransform_DEFINED
 
-#include "GrProcessor.h"
 #include "SkMatrix.h"
 #include "GrTexture.h"
-#include "GrTypes.h"
-#include "GrShaderVar.h"
 
+class GrResourceProvider;
 class GrTextureProxy;
 
 /**
@@ -25,52 +23,47 @@ public:
     GrCoordTransform()
         : fTexture(nullptr)
         , fNormalize(false)
-        , fReverseY(false)
-        , fPrecision(kDefault_GrSLPrecision) {
+        , fReverseY(false) {
         SkDEBUGCODE(fInProcessor = false);
     }
 
     /**
-     * Create a transformation that maps [0, 1] to a proxy's boundaries. The precision is inferred
-     * from the proxy size and filter. The proxy origin also implies whether a y-reversal should
-     * be performed.
+     * Create a transformation that maps [0, 1] to a proxy's boundaries. The proxy origin also
+     * implies whether a y-reversal should be performed.
      */
-    GrCoordTransform(GrResourceProvider* resourceProvider, GrTextureProxy* proxy,
-                     GrSamplerParams::FilterMode filter) {
+    GrCoordTransform(GrResourceProvider* resourceProvider, GrTextureProxy* proxy) {
         SkASSERT(proxy);
         SkDEBUGCODE(fInProcessor = false);
-        this->reset(resourceProvider, SkMatrix::I(), proxy, filter);
+        this->reset(resourceProvider, SkMatrix::I(), proxy);
     }
 
     /**
-     * Create a transformation from a matrix. The precision is inferred from the proxy size and
-     * filter. The proxy origin also implies whether a y-reversal should be performed.
+     * Create a transformation from a matrix. The proxy origin also implies whether a y-reversal
+     * should be performed.
      */
     GrCoordTransform(GrResourceProvider* resourceProvider, const SkMatrix& m,
-                     GrTextureProxy* proxy, GrSamplerParams::FilterMode filter) {
+                     GrTextureProxy* proxy) {
         SkASSERT(proxy);
         SkDEBUGCODE(fInProcessor = false);
-        this->reset(resourceProvider, m, proxy, filter);
+        this->reset(resourceProvider, m, proxy);
     }
 
     /**
      * Create a transformation that applies the matrix to a coord set.
      */
-    GrCoordTransform(const SkMatrix& m, GrSLPrecision precision = kDefault_GrSLPrecision) {
+    GrCoordTransform(const SkMatrix& m) {
         SkDEBUGCODE(fInProcessor = false);
-        this->reset(m, precision);
+        this->reset(m);
     }
 
-    void reset(GrResourceProvider*, const SkMatrix&, GrTextureProxy*,
-               GrSamplerParams::FilterMode filter, bool normalize = true);
+    void reset(GrResourceProvider*, const SkMatrix&, GrTextureProxy*, bool normalize = true);
 
-    void reset(const SkMatrix& m, GrSLPrecision precision = kDefault_GrSLPrecision) {
+    void reset(const SkMatrix& m) {
         SkASSERT(!fInProcessor);
         fMatrix = m;
         fTexture = nullptr;
         fNormalize = false;
         fReverseY = false;
-        fPrecision = precision;
     }
 
     GrCoordTransform& operator= (const GrCoordTransform& that) {
@@ -79,7 +72,6 @@ public:
         fTexture = that.fTexture;
         fNormalize = that.fNormalize;
         fReverseY = that.fReverseY;
-        fPrecision = that.fPrecision;
         return *this;
     }
 
@@ -112,7 +104,6 @@ public:
     const GrTexture* texture() const { return fTexture; }
     bool normalize() const { return fNormalize; }
     bool reverseY() const { return fReverseY; }
-    GrSLPrecision precision() const { return kHigh_GrSLPrecision; }
 
 private:
     // The textures' effect is to optionally normalize the final matrix, so a blind
@@ -124,7 +115,6 @@ private:
     const GrTexture*        fTexture;
     bool                    fNormalize;
     bool                    fReverseY;
-    GrSLPrecision           fPrecision;
     typedef SkNoncopyable INHERITED;
 
 #ifdef SK_DEBUG
diff --git a/src/effects/GrAlphaThresholdFragmentProcessor.cpp b/src/effects/GrAlphaThresholdFragmentProcessor.cpp
index b4ad0ccd2f..be890c48db 100644
--- a/src/effects/GrAlphaThresholdFragmentProcessor.cpp
+++ b/src/effects/GrAlphaThresholdFragmentProcessor.cpp
@@ -37,15 +37,13 @@ GrAlphaThresholdFragmentProcessor::GrAlphaThresholdFragmentProcessor(
         : INHERITED(OptFlags(outerThreshold))
         , fInnerThreshold(innerThreshold)
         , fOuterThreshold(outerThreshold)
-        , fImageCoordTransform(resourceProvider, SkMatrix::I(), proxy.get(),
-                               GrSamplerParams::kNone_FilterMode)
+        , fImageCoordTransform(resourceProvider, SkMatrix::I(), proxy.get())
         , fImageTextureSampler(resourceProvider, std::move(proxy))
         , fColorSpaceXform(std::move(colorSpaceXform))
         , fMaskCoordTransform(
                   resourceProvider,
                   SkMatrix::MakeTrans(SkIntToScalar(-bounds.x()), SkIntToScalar(-bounds.y())),
-                  maskProxy.get(),
-                  GrSamplerParams::kNone_FilterMode)
+                  maskProxy.get())
         , fMaskTextureSampler(resourceProvider, maskProxy) {
     this->initClassID<GrAlphaThresholdFragmentProcessor>();
     this->addCoordTransform(&fImageCoordTransform);
diff --git a/src/effects/SkDisplacementMapEffect.cpp b/src/effects/SkDisplacementMapEffect.cpp
index 9bd159d40b..bdf9cd5160 100644
--- a/src/effects/SkDisplacementMapEffect.cpp
+++ b/src/effects/SkDisplacementMapEffect.cpp
@@ -496,10 +496,9 @@ GrDisplacementMapEffect::GrDisplacementMapEffect(
         const SkISize& colorDimensions)
         : INHERITED(GrPixelConfigIsOpaque(color->config()) ? kPreservesOpaqueInput_OptimizationFlag
                                                            : kNone_OptimizationFlags)
-        , fDisplacementTransform(resourceProvider, offsetMatrix, displacement.get(),
-                                 GrSamplerParams::kNone_FilterMode)
+        , fDisplacementTransform(resourceProvider, offsetMatrix, displacement.get())
         , fDisplacementSampler(resourceProvider, displacement)
-        , fColorTransform(resourceProvider, color.get(), GrSamplerParams::kNone_FilterMode)
+        , fColorTransform(resourceProvider, color.get())
         , fDomain(color.get(), GrTextureDomain::MakeTexelDomain(SkIRect::MakeSize(colorDimensions)),
                   GrTextureDomain::kDecal_Mode)
         , fColorSampler(resourceProvider, color)
diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index be60dee15e..b178467f9c 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -1696,8 +1696,7 @@ GrGradientEffect::GrGradientEffect(const CreateArgs& args, bool isOpaque)
                 fYCoord = fAtlas->getYOffset(fRow)+SK_ScalarHalf*fAtlas->getNormalizedTexelHeight();
                 // This is 1/2 places where auto-normalization is disabled
                 fCoordTransform.reset(args.fContext->resourceProvider(), *args.fMatrix,
-                                      fAtlas->asTextureProxyRef().get(),
-                                      params.filterMode(), false);
+                                      fAtlas->asTextureProxyRef().get(), false);
                 fTextureSampler.reset(args.fContext->resourceProvider(),
                                       fAtlas->asTextureProxyRef(), params);
             } else {
@@ -1716,7 +1715,7 @@ GrGradientEffect::GrGradientEffect(const CreateArgs& args, bool isOpaque)
                 }
                 // This is 2/2 places where auto-normalization is disabled
                 fCoordTransform.reset(args.fContext->resourceProvider(), *args.fMatrix,
-                                      proxy.get(), params.filterMode(), false);
+                                      proxy.get(), false);
                 fTextureSampler.reset(args.fContext->resourceProvider(),
                                       std::move(proxy), params);
                 fYCoord = SK_ScalarHalf;
diff --git a/src/gpu/GrCoordTransform.cpp b/src/gpu/GrCoordTransform.cpp
index b22f3258fc..79d9e98b76 100644
--- a/src/gpu/GrCoordTransform.cpp
+++ b/src/gpu/GrCoordTransform.cpp
@@ -6,53 +6,11 @@
  */
 
 #include "GrCoordTransform.h"
-#include "GrCaps.h"
-#include "GrContext.h"
-#include "GrGpu.h"
 #include "GrResourceProvider.h"
 #include "GrTextureProxy.h"
 
-static GrSLPrecision compute_precision(const GrShaderCaps* caps,
-                                       int width, int height,
-                                       GrSamplerParams::FilterMode filter) {
-    // Always start at kDefault. Then if precisions differ we see if the precision needs to be
-    // increased. Our rule is that we want at least 4 subpixel values in the representation for
-    // coords between 0 to 1 when bi- or tri-lerping and 1 value when nearest filtering. Note that
-    // this still might not be enough when drawing with repeat or mirror-repeat modes but that case
-    // can be arbitrarily bad.
-    int subPixelThresh = filter > GrSamplerParams::kNone_FilterMode ? 4 : 1;
-    GrSLPrecision precision = kDefault_GrSLPrecision;
-    if (caps) {
-        if (caps->floatPrecisionVaries()) {
-            int maxD = SkTMax(width, height);
-            const GrShaderCaps::PrecisionInfo* info;
-            info = &caps->getFloatShaderPrecisionInfo(kFragment_GrShaderType, precision);
-            do {
-                SkASSERT(info->supported());
-                // Make sure there is at least 2 bits of subpixel precision in the range of
-                // texture coords from 0.5 to 1.0.
-                if ((2 << info->fBits) / maxD > subPixelThresh) {
-                    break;
-                }
-                if (kHigh_GrSLPrecision == precision) {
-                    break;
-                }
-                GrSLPrecision nextP = static_cast<GrSLPrecision>(precision + 1);
-                info = &caps->getFloatShaderPrecisionInfo(kFragment_GrShaderType, nextP);
-                if (!info->supported()) {
-                    break;
-                }
-                precision = nextP;
-            } while (true);
-        }
-    }
-
-    return precision;
-}
-
 void GrCoordTransform::reset(GrResourceProvider* resourceProvider, const SkMatrix& m,
-                             GrTextureProxy* proxy,
-                             GrSamplerParams::FilterMode filter, bool normalize) {
+                             GrTextureProxy* proxy, bool normalize) {
     SkASSERT(proxy);
     SkASSERT(!fInProcessor);
 
@@ -63,10 +21,4 @@ void GrCoordTransform::reset(GrResourceProvider* resourceProvider, const SkMatri
     fTexture = proxy->instantiate(resourceProvider);
     fNormalize = normalize;
     fReverseY = kBottomLeft_GrSurfaceOrigin == proxy->origin();
-
-    const GrCaps* caps = resourceProvider->caps();
-    fPrecision = compute_precision(caps->shaderCaps(),
-                                   proxy->worstCaseWidth(*caps),
-                                   proxy->worstCaseHeight(*caps), filter);
 }
-
diff --git a/src/gpu/GrPrimitiveProcessor.cpp b/src/gpu/GrPrimitiveProcessor.cpp
index 2aaaa0474f..b981977af3 100644
--- a/src/gpu/GrPrimitiveProcessor.cpp
+++ b/src/gpu/GrPrimitiveProcessor.cpp
@@ -10,23 +10,15 @@
 #include "GrCoordTransform.h"
 
 /**
- * The key for an individual coord transform is made up of a matrix type, a precision, and a bit
- * that indicates the source of the input coords.
+ * The key for an individual coord transform is made up of a matrix type, and a bit that indicates
+ * the source of the input coords.
  */
 enum {
     kMatrixTypeKeyBits   = 1,
-    kMatrixTypeKeyMask   = (1 << kMatrixTypeKeyBits) - 1,
-
-    kPrecisionBits       = 2,
-    kPrecisionShift      = kMatrixTypeKeyBits,
-
-    kPositionCoords_Flag = (1 << (kPrecisionShift + kPrecisionBits)),
-
-    kTransformKeyBits    = kMatrixTypeKeyBits + kPrecisionBits + 2,
+    kPositionCoords_Flag = 1 << kMatrixTypeKeyBits,
+    kTransformKeyBits    = kMatrixTypeKeyBits + 1,
 };
 
-GR_STATIC_ASSERT(kHigh_GrSLPrecision < (1 << kPrecisionBits));
-
 /**
  * We specialize the vertex code for each of these matrix types.
  */
@@ -52,9 +44,6 @@ GrPrimitiveProcessor::getTransformKey(const SkTArray<const GrCoordTransform*, tr
             key |= kPositionCoords_Flag;
         }
 
-        GR_STATIC_ASSERT(kGrSLPrecisionCount <= (1 << kPrecisionBits));
-        key |= (coordTransform->precision() << kPrecisionShift);
-
         key <<= kTransformKeyBits * t;
 
         SkASSERT(0 == (totalKey & key)); // keys for each transform ought not to overlap
diff --git a/src/gpu/effects/GrSingleTextureEffect.cpp b/src/gpu/effects/GrSingleTextureEffect.cpp
index ee6a31b019..f5d70003e6 100644
--- a/src/gpu/effects/GrSingleTextureEffect.cpp
+++ b/src/gpu/effects/GrSingleTextureEffect.cpp
@@ -15,7 +15,7 @@ GrSingleTextureEffect::GrSingleTextureEffect(GrResourceProvider* resourceProvide
                                              sk_sp<GrColorSpaceXform> colorSpaceXform,
                                              const SkMatrix& m)
         : INHERITED(optFlags)
-        , fCoordTransform(resourceProvider, m, proxy.get(), GrSamplerParams::kNone_FilterMode)
+        , fCoordTransform(resourceProvider, m, proxy.get())
         , fTextureSampler(resourceProvider, std::move(proxy))
         , fColorSpaceXform(std::move(colorSpaceXform)) {
     this->addCoordTransform(&fCoordTransform);
@@ -29,7 +29,7 @@ GrSingleTextureEffect::GrSingleTextureEffect(GrResourceProvider* resourceProvide
                                              const SkMatrix& m,
                                              GrSamplerParams::FilterMode filterMode)
         : INHERITED(optFlags)
-        , fCoordTransform(resourceProvider, m, proxy.get(), filterMode)
+        , fCoordTransform(resourceProvider, m, proxy.get())
         , fTextureSampler(resourceProvider, std::move(proxy), filterMode)
         , fColorSpaceXform(std::move(colorSpaceXform)) {
     this->addCoordTransform(&fCoordTransform);
@@ -42,7 +42,7 @@ GrSingleTextureEffect::GrSingleTextureEffect(GrResourceProvider* resourceProvide
                                              sk_sp<GrColorSpaceXform> colorSpaceXform,
                                              const SkMatrix& m, const GrSamplerParams& params)
         : INHERITED(optFlags)
-        , fCoordTransform(resourceProvider, m, proxy.get(), params.filterMode())
+        , fCoordTransform(resourceProvider, m, proxy.get())
         , fTextureSampler(resourceProvider, std::move(proxy), params)
         , fColorSpaceXform(std::move(colorSpaceXform)) {
     this->addCoordTransform(&fCoordTransform);
diff --git a/src/gpu/effects/GrYUVEffect.cpp b/src/gpu/effects/GrYUVEffect.cpp
index 14fa8c0524..f43f60a29f 100644
--- a/src/gpu/effects/GrYUVEffect.cpp
+++ b/src/gpu/effects/GrYUVEffect.cpp
@@ -158,10 +158,9 @@ private:
                    sk_sp<GrTextureProxy> vProxy, const SkMatrix yuvMatrix[3],
                    GrSamplerParams::FilterMode uvFilterMode, SkYUVColorSpace colorSpace, bool nv12)
             : INHERITED(kPreservesOpaqueInput_OptimizationFlag)
-            , fYTransform(resourceProvider, yuvMatrix[0], yProxy.get(),
-                          GrSamplerParams::kNone_FilterMode)
+            , fYTransform(resourceProvider, yuvMatrix[0], yProxy.get())
             , fYSampler(resourceProvider, std::move(yProxy))
-            , fUTransform(resourceProvider, yuvMatrix[1], uProxy.get(), uvFilterMode)
+            , fUTransform(resourceProvider, yuvMatrix[1], uProxy.get())
             , fUSampler(resourceProvider, std::move(uProxy), uvFilterMode)
             , fVSampler(resourceProvider, vProxy, uvFilterMode)
             , fColorSpace(colorSpace)
@@ -172,8 +171,7 @@ private:
         this->addCoordTransform(&fUTransform);
         this->addTextureSampler(&fUSampler);
         if (!fNV12) {
-            fVTransform = GrCoordTransform(resourceProvider, yuvMatrix[2], vProxy.get(),
-                                           uvFilterMode);
+            fVTransform = GrCoordTransform(resourceProvider, yuvMatrix[2], vProxy.get());
             this->addCoordTransform(&fVTransform);
             this->addTextureSampler(&fVSampler);
         }
diff --git a/src/gpu/glsl/GrGLSLGeometryProcessor.cpp b/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
index f13024878f..9dd1cba418 100644
--- a/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
+++ b/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
@@ -41,7 +41,8 @@ void GrGLSLGeometryProcessor::emitTransforms(GrGLSLVertexBuilder* vb,
 
         varyingType = SkToBool(SkMatrix::kPerspective_Mask & type) ? kVec3f_GrSLType :
                                                                      kVec2f_GrSLType;
-        GrSLPrecision precision = coordTransform->precision();
+        // Coord transforms are always handled at high precision
+        const GrSLPrecision precision = kHigh_GrSLPrecision;
 
         const char* uniName;