src/effects/SkPerlinNoiseShader.cpp - Issue 332523006: Fix tiled perlin noise.

Unified Diff: src/effects/SkPerlinNoiseShader.cpp

Issue 332523006: Fix tiled perlin noise. (Closed) Base URL: https://skia.googlesource.com/skia.git@master

Patch Set: add code review link Created 6 years, 6 months ago

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Index: src/effects/SkPerlinNoiseShader.cpp

diff --git a/src/effects/SkPerlinNoiseShader.cpp b/src/effects/SkPerlinNoiseShader.cpp

index bc24061d281448420216c88a3171bd72e63a0c4b..1673bce5bcad53b36c19ee691ba8beba401afbec 100644

--- a/src/effects/SkPerlinNoiseShader.cpp

+++ b/src/effects/SkPerlinNoiseShader.cpp

@@ -39,9 +39,6 @@ inline int checkNoise(int noiseValue, int limitValue, int newValue) {

if (noiseValue >= limitValue) {

noiseValue -= newValue;

}

- if (noiseValue >= limitValue - 1) {

- noiseValue -= newValue - 1;

- }

return noiseValue;

}

@@ -320,12 +317,14 @@ SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::noise2D(

const StitchData& stitchData, const SkPoint& noiseVector) const {

struct Noise {

int noisePositionIntegerValue;

+ int nextNoisePositionIntegerValue;

SkScalar noisePositionFractionValue;

Noise(SkScalar component)

{

SkScalar position = component + kPerlinNoise;

noisePositionIntegerValue = SkScalarFloorToInt(position);

noisePositionFractionValue = position - SkIntToScalar(noisePositionIntegerValue);

+ nextNoisePositionIntegerValue = noisePositionIntegerValue + 1;

}

};

Noise noiseX(noiseVector.x());

@@ -338,28 +337,36 @@ SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::noise2D(

checkNoise(noiseX.noisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);

noiseY.noisePositionIntegerValue =

checkNoise(noiseY.noisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);

+ noiseX.nextNoisePositionIntegerValue =

+ checkNoise(noiseX.nextNoisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);

+ noiseY.nextNoisePositionIntegerValue =

+ checkNoise(noiseY.nextNoisePositionIntegerValue, stitchData.fWrapY, stitchData.fHeight);

}

noiseX.noisePositionIntegerValue &= kBlockMask;

noiseY.noisePositionIntegerValue &= kBlockMask;

- int latticeIndex =

- paintingData.fLatticeSelector[noiseX.noisePositionIntegerValue] +

- noiseY.noisePositionIntegerValue;

- int nextLatticeIndex =

- paintingData.fLatticeSelector[(noiseX.noisePositionIntegerValue + 1) & kBlockMask] +

- noiseY.noisePositionIntegerValue;

+ noiseX.nextNoisePositionIntegerValue &= kBlockMask;

+ noiseY.nextNoisePositionIntegerValue &= kBlockMask;

+ int i =

+ paintingData.fLatticeSelector[noiseX.noisePositionIntegerValue];

+ int j =

+ paintingData.fLatticeSelector[noiseX.nextNoisePositionIntegerValue];

+ int b00 = (i + noiseY.noisePositionIntegerValue) & kBlockMask;

+ int b10 = (j + noiseY.noisePositionIntegerValue) & kBlockMask;

+ int b01 = (i + noiseY.nextNoisePositionIntegerValue) & kBlockMask;

+ int b11 = (j + noiseY.nextNoisePositionIntegerValue) & kBlockMask;

SkScalar sx = smoothCurve(noiseX.noisePositionFractionValue);

SkScalar sy = smoothCurve(noiseY.noisePositionFractionValue);

// This is taken 1:1 from SVG spec: http://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement

SkPoint fractionValue = SkPoint::Make(noiseX.noisePositionFractionValue,

noiseY.noisePositionFractionValue); // Offset (0,0)

- u = paintingData.fGradient[channel][latticeIndex & kBlockMask].dot(fractionValue);

+ u = paintingData.fGradient[channel][b00].dot(fractionValue);

fractionValue.fX -= SK_Scalar1; // Offset (-1,0)

- v = paintingData.fGradient[channel][nextLatticeIndex & kBlockMask].dot(fractionValue);

+ v = paintingData.fGradient[channel][b10].dot(fractionValue);

SkScalar a = SkScalarInterp(u, v, sx);

fractionValue.fY -= SK_Scalar1; // Offset (-1,-1)

- v = paintingData.fGradient[channel][(nextLatticeIndex + 1) & kBlockMask].dot(fractionValue);

+ v = paintingData.fGradient[channel][b11].dot(fractionValue);

fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1)

- u = paintingData.fGradient[channel][(latticeIndex + 1) & kBlockMask].dot(fractionValue);

+ u = paintingData.fGradient[channel][b01].dot(fractionValue);

SkScalar b = SkScalarInterp(u, v, sx);

return SkScalarInterp(a, b, sy);

}

@@ -989,13 +996,14 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

const char* chanCoord = "chanCoord";

const char* stitchData = "stitchData";

const char* ratio = "ratio";

- const char* noiseXY = "noiseXY";

const char* noiseVec = "noiseVec";

const char* noiseSmooth = "noiseSmooth";

+ const char* floorVal = "floorVal";

const char* fractVal = "fractVal";

const char* uv = "uv";

const char* ab = "ab";

const char* latticeIdx = "latticeIdx";

+ const char* bcoords = "bcoords";

const char* lattice = "lattice";

const char* inc8bit = "0.00390625"; // 1.0 / 256.0

// This is the math to convert the two 16bit integer packed into rgba 8 bit input into a

@@ -1016,32 +1024,35 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

SkString noiseCode;

- noiseCode.appendf("\tvec4 %s = vec4(floor(%s), fract(%s));", noiseXY, noiseVec, noiseVec);

+ noiseCode.appendf("\tvec4 %s;\n", floorVal);

+ noiseCode.appendf("\t%s.xy = floor(%s);\n", floorVal, noiseVec);

+ noiseCode.appendf("\t%s.zw = %s.xy + vec2(1.0);\n", floorVal, floorVal);

+ noiseCode.appendf("\tvec2 %s = fract(%s.xy);\n", fractVal, noiseVec);

sugoi 2014/06/12 17:19:53 noiseVec is already a vec2, I think, so I think yo

Stephen White 2014/06/12 17:37:18 Good catch! Done.

// smooth curve : t * t * (3 - 2 * t)

- noiseCode.appendf("\n\tvec2 %s = %s.zw * %s.zw * (vec2(3.0) - vec2(2.0) * %s.zw);",

- noiseSmooth, noiseXY, noiseXY, noiseXY);

+ noiseCode.appendf("\n\tvec2 %s = %s * %s * (vec2(3.0) - vec2(2.0) * %s);",

+ noiseSmooth, fractVal, fractVal, fractVal);

// Adjust frequencies if we're stitching tiles

if (fStitchTiles) {

noiseCode.appendf("\n\tif(%s.x >= %s.x) { %s.x -= %s.x; }",

- noiseXY, stitchData, noiseXY, stitchData);

- noiseCode.appendf("\n\tif(%s.x >= (%s.x - 1.0)) { %s.x -= (%s.x - 1.0); }",

- noiseXY, stitchData, noiseXY, stitchData);

+ floorVal, stitchData, floorVal, stitchData);

noiseCode.appendf("\n\tif(%s.y >= %s.y) { %s.y -= %s.y; }",

- noiseXY, stitchData, noiseXY, stitchData);

- noiseCode.appendf("\n\tif(%s.y >= (%s.y - 1.0)) { %s.y -= (%s.y - 1.0); }",

- noiseXY, stitchData, noiseXY, stitchData);

+ floorVal, stitchData, floorVal, stitchData);

+ noiseCode.appendf("\n\tif(%s.z >= %s.x) { %s.z -= %s.x; }",

+ floorVal, stitchData, floorVal, stitchData);

+ noiseCode.appendf("\n\tif(%s.w >= %s.y) { %s.w -= %s.y; }",

+ floorVal, stitchData, floorVal, stitchData);

}

// Get texture coordinates and normalize

- noiseCode.appendf("\n\t%s.xy = fract(floor(mod(%s.xy, 256.0)) / vec2(256.0));\n",

- noiseXY, noiseXY);

+ noiseCode.appendf("\n\t%s = fract(floor(mod(%s, 256.0)) / vec4(256.0));\n",

+ floorVal, floorVal);

// Get permutation for x

{

SkString xCoords("");

- xCoords.appendf("vec2(%s.x, 0.5)", noiseXY);

+ xCoords.appendf("vec2(%s.x, 0.5)", floorVal);

noiseCode.appendf("\n\tvec2 %s;\n\t%s.x = ", latticeIdx, latticeIdx);

builder->appendTextureLookup(&noiseCode, samplers[0], xCoords.c_str(), kVec2f_GrSLType);

@@ -1051,7 +1062,7 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

// Get permutation for x + 1

{

SkString xCoords("");

- xCoords.appendf("vec2(fract(%s.x + %s), 0.5)", noiseXY, inc8bit);

+ xCoords.appendf("vec2(%s.z, 0.5)", floorVal);

noiseCode.appendf("\n\t%s.y = ", latticeIdx);

builder->appendTextureLookup(&noiseCode, samplers[0], xCoords.c_str(), kVec2f_GrSLType);

@@ -1070,15 +1081,13 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

#endif

// Get (x,y) coordinates with the permutated x

- noiseCode.appendf("\n\t%s = fract(%s + %s.yy);", latticeIdx, latticeIdx, noiseXY);

- noiseCode.appendf("\n\tvec2 %s = %s.zw;", fractVal, noiseXY);

+ noiseCode.appendf("\n\tvec4 %s = fract(%s.xyxy + %s.yyww);", bcoords, latticeIdx, floorVal);

noiseCode.appendf("\n\n\tvec2 %s;", uv);

// Compute u, at offset (0,0)

{

SkString latticeCoords("");

- latticeCoords.appendf("vec2(%s.x, %s)", latticeIdx, chanCoord);

+ latticeCoords.appendf("vec2(%s.x, %s)", bcoords, chanCoord);

noiseCode.appendf("\n\tvec4 %s = ", lattice);

builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),

kVec2f_GrSLType);

@@ -1090,7 +1099,7 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

// Compute v, at offset (-1,0)

{

SkString latticeCoords("");

- latticeCoords.appendf("vec2(%s.y, %s)", latticeIdx, chanCoord);

+ latticeCoords.appendf("vec2(%s.y, %s)", bcoords, chanCoord);

noiseCode.append("\n\tlattice = ");

builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),

kVec2f_GrSLType);

@@ -1106,7 +1115,7 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

// Compute v, at offset (-1,-1)

{

SkString latticeCoords("");

- latticeCoords.appendf("vec2(fract(%s.y + %s), %s)", latticeIdx, inc8bit, chanCoord);

+ latticeCoords.appendf("vec2(%s.w, %s)", bcoords, chanCoord);

noiseCode.append("\n\tlattice = ");

builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),

kVec2f_GrSLType);

@@ -1118,7 +1127,7 @@ void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,

// Compute u, at offset (0,-1)

{

SkString latticeCoords("");

- latticeCoords.appendf("vec2(fract(%s.x + %s), %s)", latticeIdx, inc8bit, chanCoord);

+ latticeCoords.appendf("vec2(%s.z, %s)", bcoords, chanCoord);

noiseCode.append("\n\tlattice = ");

builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),

kVec2f_GrSLType);

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