C++ (Cpp) noiseX Examples

Example #1

File: SkPerlinNoiseShader.cpp Project: Arternis/skia

SkScalar SkPerlinNoiseShader::PerlinNoiseShaderContext::noise2D(
        int channel, 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());
    Noise noiseY(noiseVector.y());
    SkScalar u, v;
    const SkPerlinNoiseShader& perlinNoiseShader = static_cast<const SkPerlinNoiseShader&>(fShader);
    // If stitching, adjust lattice points accordingly.
    if (perlinNoiseShader.fStitchTiles) {
        noiseX.noisePositionIntegerValue =
            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;
    noiseX.nextNoisePositionIntegerValue &= kBlockMask;
    noiseY.nextNoisePositionIntegerValue &= kBlockMask;
    int i =
        fPaintingData->fLatticeSelector[noiseX.noisePositionIntegerValue];
    int j =
        fPaintingData->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 = fPaintingData->fGradient[channel][b00].dot(fractionValue);
    fractionValue.fX -= SK_Scalar1; // Offset (-1,0)
    v = fPaintingData->fGradient[channel][b10].dot(fractionValue);
    SkScalar a = SkScalarInterp(u, v, sx);
    fractionValue.fY -= SK_Scalar1; // Offset (-1,-1)
    v = fPaintingData->fGradient[channel][b11].dot(fractionValue);
    fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1)
    u = fPaintingData->fGradient[channel][b01].dot(fractionValue);
    SkScalar b = SkScalarInterp(u, v, sx);
    return SkScalarInterp(a, b, sy);
}

Example #2

File: FETurbulence.cpp Project: Xertz/EAWebKit

float FETurbulence::noise2D(int channel, PaintingData& paintingData, const FloatPoint& noiseVector)
{
    struct Noise {
        int noisePositionIntegerValue;
        float noisePositionFractionValue;

        Noise(float component)
        {
            float position = component + s_perlinNoise;
            noisePositionIntegerValue = static_cast<int>(position);
            noisePositionFractionValue = position - noisePositionIntegerValue;
        }
    };

    Noise noiseX(noiseVector.x());
    Noise noiseY(noiseVector.y());
    float* q;
    float sx, sy, a, b, u, v;

    // If stitching, adjust lattice points accordingly.
    if (m_stitchTiles) {
        checkNoise(noiseX.noisePositionIntegerValue, paintingData.wrapX, paintingData.width);
        checkNoise(noiseY.noisePositionIntegerValue, paintingData.wrapY, paintingData.height);
    }

    noiseX.noisePositionIntegerValue &= s_blockMask;
    noiseY.noisePositionIntegerValue &= s_blockMask;
    int latticeIndex = paintingData.latticeSelector[noiseX.noisePositionIntegerValue];
    int nextLatticeIndex = paintingData.latticeSelector[(noiseX.noisePositionIntegerValue + 1) & s_blockMask];

    sx = smoothCurve(noiseX.noisePositionFractionValue);
    sy = smoothCurve(noiseY.noisePositionFractionValue);

    // This is taken 1:1 from SVG spec: http://www.w3.org/TR/SVG11/filters.html#feTurbulenceElement.
    int temp = paintingData.latticeSelector[latticeIndex + noiseY.noisePositionIntegerValue];
    q = paintingData.gradient[channel][temp];
    u = noiseX.noisePositionFractionValue * q[0] + noiseY.noisePositionFractionValue * q[1];
    temp = paintingData.latticeSelector[nextLatticeIndex + noiseY.noisePositionIntegerValue];
    q = paintingData.gradient[channel][temp];
    v = (noiseX.noisePositionFractionValue - 1) * q[0] + noiseY.noisePositionFractionValue * q[1];
    a = linearInterpolation(sx, u, v);
    temp = paintingData.latticeSelector[latticeIndex + noiseY.noisePositionIntegerValue + 1];
    q = paintingData.gradient[channel][temp];
    u = noiseX.noisePositionFractionValue * q[0] + (noiseY.noisePositionFractionValue - 1) * q[1];
    temp = paintingData.latticeSelector[nextLatticeIndex + noiseY.noisePositionIntegerValue + 1];
    q = paintingData.gradient[channel][temp];
    v = (noiseX.noisePositionFractionValue - 1) * q[0] + (noiseY.noisePositionFractionValue - 1) * q[1];
    b = linearInterpolation(sx, u, v);
    return linearInterpolation(sy, a, b);
}