2D kernel initial wiring for Guassian

src/gpu/effects/GrMatrixConvolutionEffect.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "GrMatrixConvolutionEffect.h"
 #include "gl/GrGLShaderBuilder.h"
 #include "gl/GrGLEffect.h"
 #include "gl/GrGLSL.h"
@@ skipping 15 matching lines @@
     static inline void GenKey(const GrDrawEffect&, const GrGLCaps&, GrEffectKeyBuilder*);
 
     virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
 
 private:
     typedef GrGLUniformManager::UniformHandle        UniformHandle;
     typedef GrMatrixConvolutionEffect::TileMode TileMode;
     SkISize             fKernelSize;
     TileMode            fTileMode;
     bool                fConvolveAlpha;
+    bool                fUseBounds;
 
     UniformHandle       fBoundsUni;
     UniformHandle       fKernelUni;
     UniformHandle       fImageIncrementUni;
     UniformHandle       fKernelOffsetUni;
     UniformHandle       fGainUni;
     UniformHandle       fBiasUni;
 
     typedef GrGLEffect INHERITED;
 };
 
 GrGLMatrixConvolutionEffect::GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
                                                          const GrDrawEffect& drawEffect)
     : INHERITED(factory) {
     const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
     fKernelSize = m.kernelSize();
     fTileMode = m.tileMode();
     fConvolveAlpha = m.convolveAlpha();
+    fUseBounds = m.useBounds();
 }
 
 static void appendTextureLookup(GrGLShaderBuilder* builder,
                                 const GrGLShaderBuilder::TextureSampler& sampler,
                                 const char* coord,
                                 const char* bounds,
                                 GrMatrixConvolutionEffect::TileMode tileMode) {
     SkString clampedCoord;
-    switch (tileMode) {
-        case GrMatrixConvolutionEffect::kClamp_TileMode:
-            clampedCoord.printf("clamp(%s, %s.xy, %s.zw)", coord, bounds, bounds);
-            coord = clampedCoord.c_str();
-            break;
-        case GrMatrixConvolutionEffect::kRepeat_TileMode:
-            clampedCoord.printf("mod(%s - %s.xy, %s.zw - %s.xy) + %s.xy", coord, bounds, bounds, bounds, bounds);
-            coord = clampedCoord.c_str();
-            break;
-        case GrMatrixConvolutionEffect::kClampToBlack_TileMode:
-            builder->fsCodeAppendf("clamp(%s, %s.xy, %s.zw) != %s ? vec4(0, 0, 0, 0) : ", coord, bounds, bounds, coord);
-            break;
+    if (bounds != NULL) {
+        switch (tileMode) {
+            case GrMatrixConvolutionEffect::kClamp_TileMode:
+                clampedCoord.printf("clamp(%s, %s.xy, %s.zw)", coord, bounds, bounds);
+                coord = clampedCoord.c_str();
+                break;
+            case GrMatrixConvolutionEffect::kRepeat_TileMode:
+                clampedCoord.printf("mod(%s - %s.xy, %s.zw - %s.xy) + %s.xy", coord, bounds, bounds,
+                        bounds, bounds);
+                coord = clampedCoord.c_str();
+                break;
+            case GrMatrixConvolutionEffect::kClampToBlack_TileMode:
+                builder->fsCodeAppendf("clamp(%s, %s.xy, %s.zw) != %s ? vec4(0, 0, 0, 0) : ", coord,
+                        bounds, bounds, coord);
+                break;
+        }
     }
     builder->fsAppendTextureLookup(sampler, coord);
 }
 
 void GrGLMatrixConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
                                            const GrDrawEffect&,
                                            const GrEffectKey& key,
                                            const char* outputColor,
                                            const char* inputColor,
                                            const TransformedCoordsArray& coords,
                                            const TextureSamplerArray& samplers) {
     sk_ignore_unused_variable(inputColor);
     SkString coords2D = builder->ensureFSCoords2D(coords, 0);
-    fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
-                                     kVec4f_GrSLType, "Bounds");
+    if (fUseBounds) {
+        fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+                                         kVec4f_GrSLType, "Bounds");
+    }
     fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                              kVec2f_GrSLType, "ImageIncrement");
     fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
                                              kFloat_GrSLType,
                                              "Kernel",
                                              fKernelSize.width() * fKernelSize.height());
     fKernelOffsetUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                              kVec2f_GrSLType, "KernelOffset");
     fGainUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                    kFloat_GrSLType, "Gain");
     fBiasUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
                                    kFloat_GrSLType, "Bias");
 
-    const char* bounds = builder->getUniformCStr(fBoundsUni);
+    const char* bounds = NULL;
+    if (fUseBounds) {
+        bounds = builder->getUniformCStr(fBoundsUni);
+    }
     const char* kernelOffset = builder->getUniformCStr(fKernelOffsetUni);
     const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
     const char* kernel = builder->getUniformCStr(fKernelUni);
     const char* gain = builder->getUniformCStr(fGainUni);
     const char* bias = builder->getUniformCStr(fBiasUni);
     int kWidth = fKernelSize.width();
     int kHeight = fKernelSize.height();
 
     builder->fsCodeAppend("\t\tvec4 sum = vec4(0, 0, 0, 0);\n");
-    builder->fsCodeAppendf("\t\tvec2 coord = %s - %s * %s;\n", coords2D.c_str(), kernelOffset, imgInc);
-    builder->fsCodeAppendf("\t\tfor (int y = 0; y < %d; y++) {\n", kHeight);
-    builder->fsCodeAppendf("\t\t\tfor (int x = 0; x < %d; x++) {\n", kWidth);
-    builder->fsCodeAppendf("\t\t\t\tfloat k = %s[y * %d + x];\n", kernel, kWidth);
-    builder->fsCodeAppendf("\t\t\t\tvec2 coord2 = coord + vec2(x, y) * %s;\n", imgInc);
-    builder->fsCodeAppend("\t\t\t\tvec4 c = ");
-    appendTextureLookup(builder, samplers[0], "coord2", bounds, fTileMode);
-    builder->fsCodeAppend(";\n");
-    if (!fConvolveAlpha) {
-        builder->fsCodeAppend("\t\t\t\tc.rgb /= c.a;\n");
+    builder->fsCodeAppendf("\t\tvec2 coord = %s - %s * %s;\n", coords2D.c_str(), kernelOffset,
+                           imgInc);
+    builder->fsCodeAppend("\t\tfloat k;\n");
+    builder->fsCodeAppend("\t\tvec2 coord2;\n");
+    builder->fsCodeAppend("\t\tvec4 c;\n");
+
+    for (int y = 0; y < kHeight; y++) {
+        for (int x = 0; x < kWidth; x++) {
+            builder->fsCodeAppendf("\t\tk = %s[%d * %d + %d];\n", kernel, y, kWidth, x);
+            builder->fsCodeAppendf("\t\tcoord2 = coord + vec2(%d, %d) * %s;\n", x, y, imgInc);
+            builder->fsCodeAppend("\t\tc = ");
+            appendTextureLookup(builder, samplers[0], "coord2", bounds, fTileMode);
+            builder->fsCodeAppend(";\n");
+            if (!fConvolveAlpha) {
+               builder->fsCodeAppend("\t\tc.rgb /= c.a;\n");
+            }
+            builder->fsCodeAppend("\t\tsum += c * k;\n");
+        }
     }
-    builder->fsCodeAppend("\t\t\t\tsum += c * k;\n");
-    builder->fsCodeAppend("\t\t\t}\n");
-    builder->fsCodeAppend("\t\t}\n");
     if (fConvolveAlpha) {
         builder->fsCodeAppendf("\t\t%s = sum * %s + %s;\n", outputColor, gain, bias);
         builder->fsCodeAppendf("\t\t%s.rgb = clamp(%s.rgb, 0.0, %s.a);\n",
             outputColor, outputColor, outputColor);
     } else {
-        builder->fsCodeAppend("\t\tvec4 c = ");
+        builder->fsCodeAppend("\t\tc = ");
         appendTextureLookup(builder, samplers[0], coords2D.c_str(), bounds, fTileMode);
         builder->fsCodeAppend(";\n");
         builder->fsCodeAppendf("\t\t%s.a = c.a;\n", outputColor);
         builder->fsCodeAppendf("\t\t%s.rgb = sum.rgb * %s + %s;\n", outputColor, gain, bias);
         builder->fsCodeAppendf("\t\t%s.rgb *= %s.a;\n", outputColor, outputColor);
     }
 }
 
 namespace {
 
 int encodeXY(int x, int y) {
     SkASSERT(x >= 1 && y >= 1 && x * y <= 32);
     if (y < x)
         return 0x40 | encodeXY(y, x);
     else
         return (0x40 >> x) | (y - x);
 }
 
 };
 
 void GrGLMatrixConvolutionEffect::GenKey(const GrDrawEffect& drawEffect,
                                          const GrGLCaps&, GrEffectKeyBuilder* b) {
     const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
     uint32_t key = encodeXY(m.kernelSize().width(), m.kernelSize().height());
     key |= m.tileMode() << 7;
     key |= m.convolveAlpha() ? 1 << 9 : 0;
+    key |= m.useBounds() ? 1 << 10 : 0;
     b->add32(key);
 }
 
 void GrGLMatrixConvolutionEffect::setData(const GrGLUniformManager& uman,
                                           const GrDrawEffect& drawEffect) {
     const GrMatrixConvolutionEffect& conv = drawEffect.castEffect<GrMatrixConvolutionEffect>();
     GrTexture& texture = *conv.texture(0);
     // the code we generated was for a specific kernel size
     SkASSERT(conv.kernelSize() == fKernelSize);
     SkASSERT(conv.tileMode() == fTileMode);
     float imageIncrement[2];
     float ySign = texture.origin() == kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
     imageIncrement[0] = 1.0f / texture.width();
     imageIncrement[1] = ySign / texture.height();
     uman.set2fv(fImageIncrementUni, 1, imageIncrement);
     uman.set2fv(fKernelOffsetUni, 1, conv.kernelOffset());
     uman.set1fv(fKernelUni, fKernelSize.width() * fKernelSize.height(), conv.kernel());
     uman.set1f(fGainUni, conv.gain());
     uman.set1f(fBiasUni, conv.bias());
-    const SkIRect& bounds = conv.bounds();
-    float left = (float) bounds.left() / texture.width();
-    float top = (float) bounds.top() / texture.height();
-    float right = (float) bounds.right() / texture.width();
-    float bottom = (float) bounds.bottom() / texture.height();
-    if (texture.origin() == kBottomLeft_GrSurfaceOrigin) {
-        uman.set4f(fBoundsUni, left, 1.0f - bottom, right, 1.0f - top);
-    } else {
-        uman.set4f(fBoundsUni, left, top, right, bottom);
+    if (fUseBounds) {
+        const SkIRect& bounds = conv.bounds();
+        float left = (float) bounds.left() / texture.width();
+        float top = (float) bounds.top() / texture.height();
+        float right = (float) bounds.right() / texture.width();
+        float bottom = (float) bounds.bottom() / texture.height();
+        if (texture.origin() == kBottomLeft_GrSurfaceOrigin) {
+            uman.set4f(fBoundsUni, left, 1.0f - bottom, right, 1.0f - top);
+        } else {
+            uman.set4f(fBoundsUni, left, top, right, bottom);
+        }
     }
 }
 
 GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
                                                      const SkIRect& bounds,
                                                      const SkISize& kernelSize,
                                                      const SkScalar* kernel,
                                                      SkScalar gain,
                                                      SkScalar bias,
                                                      const SkIPoint& kernelOffset,
                                                      TileMode tileMode,
-                                                     bool convolveAlpha)
+                                                     bool convolveAlpha,
+                                                     bool useBounds)
   : INHERITED(texture, MakeDivByTextureWHMatrix(texture)),
     fBounds(bounds),
     fKernelSize(kernelSize),
     fGain(SkScalarToFloat(gain)),
     fBias(SkScalarToFloat(bias) / 255.0f),
     fTileMode(tileMode),
-    fConvolveAlpha(convolveAlpha) {
-    fKernel = new float[kernelSize.width() * kernelSize.height()];
+    fConvolveAlpha(convolveAlpha),
+    fUseBounds(useBounds) {
     for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
         fKernel[i] = SkScalarToFloat(kernel[i]);
     }
     fKernelOffset[0] = static_cast<float>(kernelOffset.x());
     fKernelOffset[1] = static_cast<float>(kernelOffset.y());
     this->setWillNotUseInputColor();
 }
 
+GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
+                                                     const SkIRect& bounds,
+                                                     const SkISize& kernelSize,
+                                                     SkScalar gain,
+                                                     SkScalar bias,
+                                                     const SkIPoint& kernelOffset,
+                                                     TileMode tileMode,
+                                                     bool convolveAlpha,
+                                                     bool useBounds,
+                                                     SkScalar sigmaX,
+                                                     SkScalar sigmaY)
+  : INHERITED(texture, MakeDivByTextureWHMatrix(texture)),
+    fBounds(bounds),
+    fKernelSize(kernelSize),
+    fGain(SkScalarToFloat(gain)),
+    fBias(SkScalarToFloat(bias) / 255.0f),
+    fTileMode(tileMode),
+    fConvolveAlpha(convolveAlpha),
+    fUseBounds(useBounds) {
+    int width = kernelSize.width();
+    int height = kernelSize.height();
+    SkASSERT(width * height <= MAX_KERNEL_SIZE);
+    float sum = 0.0f;
+    float sigmaXDenom = 1.0 / (2.0 * sigmaX * sigmaX);
+    float sigmaYDenom = 1.0 / (2.0 * sigmaY * sigmaY);
+    int xRadius = width / 2;
+    int yRadius = height / 2;
+    for (int x = 0; x < width; x++) {
+      float xTerm = static_cast<float>(x - xRadius);
+      xTerm = SkScalarSquare(xTerm) * sigmaXDenom;
+      for (int y = 0; y < height; y++) {
+        float yTerm = static_cast<float>(y - yRadius);
+
+        float xyTerm = sk_float_exp(-(xTerm + SkScalarSquare(yTerm) * sigmaYDenom));
+        // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian
+        // is dropped here, since we renormalize the kernel below.

[Stephen White, 2014/07/25 20:43:18]

I'm not fond of baking the Gaussian-specific stuff into the 2D convolution.
Could we keep it generic, and have the caller create a Gaussian with it?

+        fKernel[y * width + x] = xyTerm;
+        sum += xyTerm;
+      }
+    }
+    // Normalize the kernel
+    float scale = 1.0f / sum;
+    for (int i = 0; i < width * height; ++i) {
+        fKernel[i] *= scale;
+    }
+
+    fKernelOffset[0] = static_cast<float>(kernelOffset.x());
+    fKernelOffset[1] = static_cast<float>(kernelOffset.y());
+    this->setWillNotUseInputColor();
+}
+
 GrMatrixConvolutionEffect::~GrMatrixConvolutionEffect() {
-    delete[] fKernel;
 }
 
 const GrBackendEffectFactory& GrMatrixConvolutionEffect::getFactory() const {
     return GrTBackendEffectFactory<GrMatrixConvolutionEffect>::getInstance();
 }
 
 bool GrMatrixConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
     const GrMatrixConvolutionEffect& s = CastEffect<GrMatrixConvolutionEffect>(sBase);
     return this->texture(0) == s.texture(0) &&
            fKernelSize == s.kernelSize() &&
@@ skipping 24 matching lines @@
     SkScalar gain = random->nextSScalar1();
     SkScalar bias = random->nextSScalar1();
     SkIPoint kernelOffset = SkIPoint::Make(random->nextRangeU(0, kernelSize.width()),
                                            random->nextRangeU(0, kernelSize.height()));
     SkIRect bounds = SkIRect::MakeXYWH(random->nextRangeU(0, textures[texIdx]->width()),
                                        random->nextRangeU(0, textures[texIdx]->height()),
                                        random->nextRangeU(0, textures[texIdx]->width()),
                                        random->nextRangeU(0, textures[texIdx]->height()));
     TileMode tileMode = static_cast<TileMode>(random->nextRangeU(0, 2));
     bool convolveAlpha = random->nextBool();
+    bool useBounds = random->nextBool();
     return GrMatrixConvolutionEffect::Create(textures[texIdx],
                                              bounds,
                                              kernelSize,
                                              kernel.get(),
                                              gain,
                                              bias,
                                              kernelOffset,
                                              tileMode,
-                                             convolveAlpha);
+                                             convolveAlpha,
+                                             useBounds);
 }