/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkPerlinNoiseShader.h"
#include "SkArenaAlloc.h"
#include "SkDither.h"
#include "SkColorFilter.h"
#include "SkMakeUnique.h"
#include "SkReadBuffer.h"
#include "SkShader.h"
#include "SkString.h"
#include "SkUnPreMultiply.h"
#include "SkWriteBuffer.h"
#if SK_SUPPORT_GPU
#include "GrContext.h"
#include "GrContextPriv.h"
#include "GrCoordTransform.h"
#include "SkGr.h"
#include "effects/GrConstColorProcessor.h"
#include "glsl/GrGLSLFragmentProcessor.h"
#include "glsl/GrGLSLFragmentShaderBuilder.h"
#include "glsl/GrGLSLProgramDataManager.h"
#include "glsl/GrGLSLUniformHandler.h"
#endif
static const int kBlockSize = 256;
static const int kBlockMask = kBlockSize - 1;
static const int kPerlinNoise = 4096;
static const int kRandMaximum = SK_MaxS32; // 2**31 - 1
static uint8_t improved_noise_permutations[] = {
151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140, 36, 103,
30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234, 75, 0, 26,
197, 62, 94, 252, 219, 203, 117, 35, 11, 32, 57, 177, 33, 88, 237, 149, 56, 87, 174,
20, 125, 136, 171, 168, 68, 175, 74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158, 231,
83, 111, 229, 122, 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143,
54, 65, 25, 63, 161, 1, 216, 80, 73, 209, 76, 132, 187, 208, 89, 18, 169, 200, 196,
135, 130, 116, 188, 159, 86, 164, 100, 109, 198, 173, 186, 3, 64, 52, 217, 226, 250, 124,
123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212, 207, 206, 59, 227, 47, 16, 58, 17,
182, 189, 28, 42, 223, 183, 170, 213, 119, 248, 152, 2, 44, 154, 163, 70, 221, 153, 101,
155, 167, 43, 172, 9, 129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224, 232, 178, 185,
112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, 81,
51, 145, 235, 249, 14, 239, 107, 49, 192, 214, 31, 181, 199, 106, 157, 184, 84, 204, 176,
115, 121, 50, 45, 127, 4, 150, 254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243,
141, 128, 195, 78, 66, 215, 61, 156, 180,
151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140, 36, 103,
30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234, 75, 0, 26,
197, 62, 94, 252, 219, 203, 117, 35, 11, 32, 57, 177, 33, 88, 237, 149, 56, 87, 174,
20, 125, 136, 171, 168, 68, 175, 74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158, 231,
83, 111, 229, 122, 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143,
54, 65, 25, 63, 161, 1, 216, 80, 73, 209, 76, 132, 187, 208, 89, 18, 169, 200, 196,
135, 130, 116, 188, 159, 86, 164, 100, 109, 198, 173, 186, 3, 64, 52, 217, 226, 250, 124,
123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212, 207, 206, 59, 227, 47, 16, 58, 17,
182, 189, 28, 42, 223, 183, 170, 213, 119, 248, 152, 2, 44, 154, 163, 70, 221, 153, 101,
155, 167, 43, 172, 9, 129, 22, 39, 253, 19, 98, 108, 110, 79, 113, 224, 232, 178, 185,
112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, 81,
51, 145, 235, 249, 14, 239, 107, 49, 192, 214, 31, 181, 199, 106, 157, 184, 84, 204, 176,
115, 121, 50, 45, 127, 4, 150, 254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243,
141, 128, 195, 78, 66, 215, 61, 156, 180
};
class SkPerlinNoiseShaderImpl : public SkShaderBase {
public:
struct StitchData {
StitchData()
: fWidth(0)
, fWrapX(0)
, fHeight(0)
, fWrapY(0)
{}
bool operator==(const StitchData& other) const {
return fWidth == other.fWidth &&
fWrapX == other.fWrapX &&
fHeight == other.fHeight &&
fWrapY == other.fWrapY;
}
int fWidth; // How much to subtract to wrap for stitching.
int fWrapX; // Minimum value to wrap.
int fHeight;
int fWrapY;
};
struct PaintingData {
PaintingData(const SkISize& tileSize, SkScalar seed,
SkScalar baseFrequencyX, SkScalar baseFrequencyY,
const SkMatrix& matrix)
{
SkVector vec[2] = {
{ SkScalarInvert(baseFrequencyX), SkScalarInvert(baseFrequencyY) },
{ SkIntToScalar(tileSize.fWidth), SkIntToScalar(tileSize.fHeight) },
};
matrix.mapVectors(vec, 2);
fBaseFrequency.set(SkScalarInvert(vec[0].fX), SkScalarInvert(vec[0].fY));
fTileSize.set(SkScalarRoundToInt(vec[1].fX), SkScalarRoundToInt(vec[1].fY));
this->init(seed);
if (!fTileSize.isEmpty()) {
this->stitch();
}
#if SK_SUPPORT_GPU
SkImageInfo info = SkImageInfo::MakeA8(kBlockSize, 1);
SkPixmap permutationsPixmap(info, fLatticeSelector, info.minRowBytes());
fPermutationsImage = SkImage::MakeFromRaster(permutationsPixmap, nullptr, nullptr);
info = SkImageInfo::MakeN32Premul(kBlockSize, 4);
SkPixmap noisePixmap(info, fNoise[0][0], info.minRowBytes());
fNoiseImage = SkImage::MakeFromRaster(noisePixmap, nullptr, nullptr);
info = SkImageInfo::MakeA8(256, 1);
SkPixmap impPermutationsPixmap(info, improved_noise_permutations, info.minRowBytes());
fImprovedPermutationsImage = SkImage::MakeFromRaster(impPermutationsPixmap, nullptr,
nullptr);
static uint8_t gradients[] = { 2, 2, 1, 0,
0, 2, 1, 0,
2, 0, 1, 0,
0, 0, 1, 0,
2, 1, 2, 0,
0, 1, 2, 0,
2, 1, 0, 0,
0, 1, 0, 0,
1, 2, 2, 0,
1, 0, 2, 0,
1, 2, 0, 0,
1, 0, 0, 0,
2, 2, 1, 0,
1, 0, 2, 0,
0, 2, 1, 0,
1, 0, 0, 0 };
info = SkImageInfo::MakeN32Premul(16, 1);
SkPixmap gradPixmap(info, gradients, info.minRowBytes());
fGradientImage = SkImage::MakeFromRaster(gradPixmap, nullptr, nullptr);
#endif
}
#if SK_SUPPORT_GPU
PaintingData(const PaintingData& that)
: fSeed(that.fSeed)
, fTileSize(that.fTileSize)
, fBaseFrequency(that.fBaseFrequency)
, fStitchDataInit(that.fStitchDataInit)
, fPermutationsImage(that.fPermutationsImage)
, fNoiseImage(that.fNoiseImage)
, fImprovedPermutationsImage(that.fImprovedPermutationsImage)
, fGradientImage(that.fGradientImage) {
memcpy(fLatticeSelector, that.fLatticeSelector, sizeof(fLatticeSelector));
memcpy(fNoise, that.fNoise, sizeof(fNoise));
memcpy(fGradient, that.fGradient, sizeof(fGradient));
}
#endif
int fSeed;
uint8_t fLatticeSelector[kBlockSize];
uint16_t fNoise[4][kBlockSize][2];
SkPoint fGradient[4][kBlockSize];
SkISize fTileSize;
SkVector fBaseFrequency;
StitchData fStitchDataInit;
private:
#if SK_SUPPORT_GPU
sk_sp<SkImage> fPermutationsImage;
sk_sp<SkImage> fNoiseImage;
sk_sp<SkImage> fImprovedPermutationsImage;
sk_sp<SkImage> fGradientImage;
#endif
inline int random() {
static const int gRandAmplitude = 16807; // 7**5; primitive root of m
static const int gRandQ = 127773; // m / a
static const int gRandR = 2836; // m % a
int result = gRandAmplitude * (fSeed % gRandQ) - gRandR * (fSeed / gRandQ);
if (result <= 0)
result += kRandMaximum;
fSeed = result;
return result;
}
// Only called once. Could be part of the constructor.
void init(SkScalar seed)
{
static const SkScalar gInvBlockSizef = SkScalarInvert(SkIntToScalar(kBlockSize));
// According to the SVG spec, we must truncate (not round) the seed value.
fSeed = SkScalarTruncToInt(seed);
// The seed value clamp to the range [1, kRandMaximum - 1].
if (fSeed <= 0) {
fSeed = -(fSeed % (kRandMaximum - 1)) + 1;
}
if (fSeed > kRandMaximum - 1) {
fSeed = kRandMaximum - 1;
}
for (int channel = 0; channel < 4; ++channel) {
for (int i = 0; i < kBlockSize; ++i) {
fLatticeSelector[i] = i;
fNoise[channel][i][0] = (random() % (2 * kBlockSize));
fNoise[channel][i][1] = (random() % (2 * kBlockSize));
}
}
for (int i = kBlockSize - 1; i > 0; --i) {
int k = fLatticeSelector[i];
int j = random() % kBlockSize;
SkASSERT(j >= 0);
SkASSERT(j < kBlockSize);
fLatticeSelector[i] = fLatticeSelector[j];
fLatticeSelector[j] = k;
}
// Perform the permutations now
{
// Copy noise data
uint16_t noise[4][kBlockSize][2];
for (int i = 0; i < kBlockSize; ++i) {
for (int channel = 0; channel < 4; ++channel) {
for (int j = 0; j < 2; ++j) {
noise[channel][i][j] = fNoise[channel][i][j];
}
}
}
// Do permutations on noise data
for (int i = 0; i < kBlockSize; ++i) {
for (int channel = 0; channel < 4; ++channel) {
for (int j = 0; j < 2; ++j) {
fNoise[channel][i][j] = noise[channel][fLatticeSelector[i]][j];
}
}
}
}
// Half of the largest possible value for 16 bit unsigned int
static const SkScalar gHalfMax16bits = 32767.5f;
// Compute gradients from permutated noise data
for (int channel = 0; channel < 4; ++channel) {
for (int i = 0; i < kBlockSize; ++i) {
fGradient[channel][i] = SkPoint::Make(
(fNoise[channel][i][0] - kBlockSize) * gInvBlockSizef,
(fNoise[channel][i][1] - kBlockSize) * gInvBlockSizef);
fGradient[channel][i].normalize();
// Put the normalized gradient back into the noise data
fNoise[channel][i][0] = SkScalarRoundToInt(
(fGradient[channel][i].fX + 1) * gHalfMax16bits);
fNoise[channel][i][1] = SkScalarRoundToInt(
(fGradient[channel][i].fY + 1) * gHalfMax16bits);
}
}
}
// Only called once. Could be part of the constructor.
void stitch() {
SkScalar tileWidth = SkIntToScalar(fTileSize.width());
SkScalar tileHeight = SkIntToScalar(fTileSize.height());
SkASSERT(tileWidth > 0 && tileHeight > 0);
// When stitching tiled turbulence, the frequencies must be adjusted
// so that the tile borders will be continuous.
if (fBaseFrequency.fX) {
SkScalar lowFrequencx =
SkScalarFloorToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
SkScalar highFrequencx =
SkScalarCeilToScalar(tileWidth * fBaseFrequency.fX) / tileWidth;
// BaseFrequency should be non-negative according to the standard.
if (fBaseFrequency.fX / lowFrequencx < highFrequencx / fBaseFrequency.fX) {
fBaseFrequency.fX = lowFrequencx;
} else {
fBaseFrequency.fX = highFrequencx;
}
}
if (fBaseFrequency.fY) {
SkScalar lowFrequency =
SkScalarFloorToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
SkScalar highFrequency =
SkScalarCeilToScalar(tileHeight * fBaseFrequency.fY) / tileHeight;
if (fBaseFrequency.fY / lowFrequency < highFrequency / fBaseFrequency.fY) {
fBaseFrequency.fY = lowFrequency;
} else {
fBaseFrequency.fY = highFrequency;
}
}
// Set up TurbulenceInitial stitch values.
fStitchDataInit.fWidth =
SkScalarRoundToInt(tileWidth * fBaseFrequency.fX);
fStitchDataInit.fWrapX = kPerlinNoise + fStitchDataInit.fWidth;
fStitchDataInit.fHeight =
SkScalarRoundToInt(tileHeight * fBaseFrequency.fY);
fStitchDataInit.fWrapY = kPerlinNoise + fStitchDataInit.fHeight;
}
public:
#if SK_SUPPORT_GPU
const sk_sp<SkImage> getPermutationsImage() const { return fPermutationsImage; }
const sk_sp<SkImage> getNoiseImage() const { return fNoiseImage; }
const sk_sp<SkImage> getImprovedPermutationsImage() const {
return fImprovedPermutationsImage;
}
const sk_sp<SkImage> getGradientImage() const { return fGradientImage; }
#endif
};
/**
* About the noise types : the difference between the first 2 is just minor tweaks to the
* algorithm, they're not 2 entirely different noises. The output looks different, but once the
* noise is generated in the [1, -1] range, the output is brought back in the [0, 1] range by
* doing :
* kFractalNoise_Type : noise * 0.5 + 0.5
* kTurbulence_Type : abs(noise)
* Very little differences between the 2 types, although you can tell the difference visually.
* "Improved" is based on the Improved Perlin Noise algorithm described at
* http://mrl.nyu.edu/~perlin/noise/. It is quite distinct from the other two, and the noise is
* a 2D slice of a 3D noise texture. Minor changes to the Z coordinate will result in minor
* changes to the noise, making it suitable for animated noise.
*/
enum Type {
kFractalNoise_Type,
kTurbulence_Type,
kImprovedNoise_Type,
kLast_Type = kImprovedNoise_Type
};
static const int kMaxOctaves = 255; // numOctaves must be <= 0 and <= kMaxOctaves
SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::Type type, SkScalar baseFrequencyX,
SkScalar baseFrequencyY, int numOctaves, SkScalar seed,
const SkISize* tileSize);
class PerlinNoiseShaderContext : public Context {
public:
PerlinNoiseShaderContext(const SkPerlinNoiseShaderImpl& shader, const ContextRec&);
void shadeSpan(int x, int y, SkPMColor[], int count) override;
private:
SkPMColor shade(const SkPoint& point, StitchData& stitchData) const;
SkScalar calculateTurbulenceValueForPoint(
int channel,
StitchData& stitchData, const SkPoint& point) const;
SkScalar calculateImprovedNoiseValueForPoint(int channel, const SkPoint& point) const;
SkScalar noise2D(int channel,
const StitchData& stitchData, const SkPoint& noiseVector) const;
SkMatrix fMatrix;
PaintingData fPaintingData;
typedef Context INHERITED;
};
#if SK_SUPPORT_GPU
std::unique_ptr<GrFragmentProcessor> asFragmentProcessor(const GrFPArgs&) const override;
#endif
SK_TO_STRING_OVERRIDE()
SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPerlinNoiseShaderImpl)
protected:
void flatten(SkWriteBuffer&) const override;
Context* onMakeContext(const ContextRec&, SkArenaAlloc*) const override;
private:
const SkPerlinNoiseShaderImpl::Type fType;
const SkScalar fBaseFrequencyX;
const SkScalar fBaseFrequencyY;
const int fNumOctaves;
const SkScalar fSeed;
const SkISize fTileSize;
const bool fStitchTiles;
friend class ::SkPerlinNoiseShader;
typedef SkShaderBase INHERITED;
};
namespace {
// noiseValue is the color component's value (or color)
// limitValue is the maximum perlin noise array index value allowed
// newValue is the current noise dimension (either width or height)
inline int checkNoise(int noiseValue, int limitValue, int newValue) {
// If the noise value would bring us out of bounds of the current noise array while we are
// stiching noise tiles together, wrap the noise around the current dimension of the noise to
// stay within the array bounds in a continuous fashion (so that tiling lines are not visible)
if (noiseValue >= limitValue) {
noiseValue -= newValue;
}
return noiseValue;
}
inline SkScalar smoothCurve(SkScalar t) {
return t * t * (3 - 2 * t);
}
} // end namespace
SkPerlinNoiseShaderImpl::SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::Type type,
SkScalar baseFrequencyX,
SkScalar baseFrequencyY,
int numOctaves,
SkScalar seed,
const SkISize* tileSize)
: fType(type)
, fBaseFrequencyX(baseFrequencyX)
, fBaseFrequencyY(baseFrequencyY)
, fNumOctaves(numOctaves > kMaxOctaves ? kMaxOctaves : numOctaves/*[0,255] octaves allowed*/)
, fSeed(seed)
, fTileSize(nullptr == tileSize ? SkISize::Make(0, 0) : *tileSize)
, fStitchTiles(!fTileSize.isEmpty())
{
SkASSERT(numOctaves >= 0 && numOctaves <= kMaxOctaves);
}
sk_sp<SkFlattenable> SkPerlinNoiseShaderImpl::CreateProc(SkReadBuffer& buffer) {
Type type = buffer.read32LE(kLast_Type);
SkScalar freqX = buffer.readScalar();
SkScalar freqY = buffer.readScalar();
int octaves = buffer.read32LE<int>(kMaxOctaves);
SkScalar seed = buffer.readScalar();
SkISize tileSize;
tileSize.fWidth = buffer.readInt();
tileSize.fHeight = buffer.readInt();
switch (type) {
case kFractalNoise_Type:
return SkPerlinNoiseShader::MakeFractalNoise(freqX, freqY, octaves, seed, &tileSize);
case kTurbulence_Type:
return SkPerlinNoiseShader::MakeTurbulence(freqX, freqY, octaves, seed, &tileSize);
case kImprovedNoise_Type:
return SkPerlinNoiseShader::MakeImprovedNoise(freqX, freqY, octaves, seed);
default:
// Really shouldn't get here b.c. of earlier check on type
buffer.validate(false);
return nullptr;
}
}
void SkPerlinNoiseShaderImpl::flatten(SkWriteBuffer& buffer) const {
buffer.writeInt((int) fType);
buffer.writeScalar(fBaseFrequencyX);
buffer.writeScalar(fBaseFrequencyY);
buffer.writeInt(fNumOctaves);
buffer.writeScalar(fSeed);
buffer.writeInt(fTileSize.fWidth);
buffer.writeInt(fTileSize.fHeight);
}
SkScalar SkPerlinNoiseShaderImpl::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 SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(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);
if (sx < 0 || sy < 0 || sx > 1 || sy > 1) {
return 0; // Check for pathological inputs.
}
// 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);
}
SkScalar SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::calculateTurbulenceValueForPoint(
int channel, StitchData& stitchData, const SkPoint& point) const {
const SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(fShader);
if (perlinNoiseShader.fStitchTiles) {
// Set up TurbulenceInitial stitch values.
stitchData = fPaintingData.fStitchDataInit;
}
SkScalar turbulenceFunctionResult = 0;
SkPoint noiseVector(SkPoint::Make(point.x() * fPaintingData.fBaseFrequency.fX,
point.y() * fPaintingData.fBaseFrequency.fY));
SkScalar ratio = SK_Scalar1;
for (int octave = 0; octave < perlinNoiseShader.fNumOctaves; ++octave) {
SkScalar noise = noise2D(channel, stitchData, noiseVector);
SkScalar numer = (perlinNoiseShader.fType == kFractalNoise_Type) ?
noise : SkScalarAbs(noise);
turbulenceFunctionResult += numer / ratio;
noiseVector.fX *= 2;
noiseVector.fY *= 2;
ratio *= 2;
if (perlinNoiseShader.fStitchTiles) {
// Update stitch values
stitchData.fWidth *= 2;
stitchData.fWrapX = stitchData.fWidth + kPerlinNoise;
stitchData.fHeight *= 2;
stitchData.fWrapY = stitchData.fHeight + kPerlinNoise;
}
}
// The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
// by fractalNoise and (turbulenceFunctionResult) by turbulence.
if (perlinNoiseShader.fType == kFractalNoise_Type) {
turbulenceFunctionResult = SkScalarHalf(turbulenceFunctionResult + 1);
}
if (channel == 3) { // Scale alpha by paint value
turbulenceFunctionResult *= SkIntToScalar(getPaintAlpha()) / 255;
}
// Clamp result
return SkScalarPin(turbulenceFunctionResult, 0, SK_Scalar1);
}
////////////////////////////////////////////////////////////////////////////////////////////////////
// Improved Perlin Noise based on Java implementation found at http://mrl.nyu.edu/~perlin/noise/
static SkScalar fade(SkScalar t) {
return t * t * t * (t * (t * 6 - 15) + 10);
}
static SkScalar lerp(SkScalar t, SkScalar a, SkScalar b) {
return a + t * (b - a);
}
static SkScalar grad(int hash, SkScalar x, SkScalar y, SkScalar z) {
int h = hash & 15;
SkScalar u = h < 8 ? x : y;
SkScalar v = h < 4 ? y : h == 12 || h == 14 ? x : z;
return ((h & 1) == 0 ? u : -u) + ((h & 2) == 0 ? v : -v);
}
SkScalar SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::calculateImprovedNoiseValueForPoint(
int channel, const SkPoint& point) const {
const SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(fShader);
SkScalar x = point.fX * perlinNoiseShader.fBaseFrequencyX;
SkScalar y = point.fY * perlinNoiseShader.fBaseFrequencyY;
// z offset between different channels, chosen arbitrarily
static const SkScalar CHANNEL_DELTA = 1000.0f;
SkScalar z = channel * CHANNEL_DELTA + perlinNoiseShader.fSeed;
SkScalar result = 0;
SkScalar ratio = SK_Scalar1;
for (int i = 0; i < perlinNoiseShader.fNumOctaves; i++) {
int X = SkScalarFloorToInt(x) & 255;
int Y = SkScalarFloorToInt(y) & 255;
int Z = SkScalarFloorToInt(z) & 255;
SkScalar px = x - SkScalarFloorToScalar(x);
SkScalar py = y - SkScalarFloorToScalar(y);
SkScalar pz = z - SkScalarFloorToScalar(z);
SkScalar u = fade(px);
SkScalar v = fade(py);
SkScalar w = fade(pz);
uint8_t* permutations = improved_noise_permutations;
int A = permutations[X] + Y;
int AA = permutations[A] + Z;
int AB = permutations[A + 1] + Z;
int B = permutations[X + 1] + Y;
int BA = permutations[B] + Z;
int BB = permutations[B + 1] + Z;
result += lerp(w, lerp(v, lerp(u, grad(permutations[AA ], px , py , pz ),
grad(permutations[BA ], px - 1, py , pz )),
lerp(u, grad(permutations[AB ], px , py - 1, pz ),
grad(permutations[BB ], px - 1, py - 1, pz ))),
lerp(v, lerp(u, grad(permutations[AA + 1], px , py , pz - 1),
grad(permutations[BA + 1], px - 1, py , pz - 1)),
lerp(u, grad(permutations[AB + 1], px , py - 1, pz - 1),
grad(permutations[BB + 1], px - 1, py - 1, pz - 1)))) /
ratio;
x *= 2;
y *= 2;
ratio *= 2;
}
result = SkScalarClampMax((result + 1.0f) / 2.0f, 1.0f);
return result;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
SkPMColor SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::shade(
const SkPoint& point, StitchData& stitchData) const {
const SkPerlinNoiseShaderImpl& perlinNoiseShader = static_cast<const SkPerlinNoiseShaderImpl&>(fShader);
SkPoint newPoint;
fMatrix.mapPoints(&newPoint, &point, 1);
newPoint.fX = SkScalarRoundToScalar(newPoint.fX);
newPoint.fY = SkScalarRoundToScalar(newPoint.fY);
U8CPU rgba[4];
for (int channel = 3; channel >= 0; --channel) {
SkScalar value;
if (perlinNoiseShader.fType == kImprovedNoise_Type) {
value = calculateImprovedNoiseValueForPoint(channel, newPoint);
}
else {
value = calculateTurbulenceValueForPoint(channel, stitchData, newPoint);
}
rgba[channel] = SkScalarFloorToInt(255 * value);
}
return SkPreMultiplyARGB(rgba[3], rgba[0], rgba[1], rgba[2]);
}
SkShaderBase::Context* SkPerlinNoiseShaderImpl::onMakeContext(const ContextRec& rec,
SkArenaAlloc* alloc) const {
return alloc->make<PerlinNoiseShaderContext>(*this, rec);
}
static inline SkMatrix total_matrix(const SkShaderBase::ContextRec& rec,
const SkShaderBase& shader) {
SkMatrix matrix = SkMatrix::Concat(*rec.fMatrix, shader.getLocalMatrix());
if (rec.fLocalMatrix) {
matrix.preConcat(*rec.fLocalMatrix);
}
return matrix;
}
SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::PerlinNoiseShaderContext(
const SkPerlinNoiseShaderImpl& shader, const ContextRec& rec)
: INHERITED(shader, rec)
, fMatrix(total_matrix(rec, shader)) // used for temp storage, adjusted below
, fPaintingData(shader.fTileSize, shader.fSeed, shader.fBaseFrequencyX,
shader.fBaseFrequencyY, fMatrix)
{
// This (1,1) translation is due to WebKit's 1 based coordinates for the noise
// (as opposed to 0 based, usually). The same adjustment is in the setData() function.
fMatrix.setTranslate(-fMatrix.getTranslateX() + SK_Scalar1,
-fMatrix.getTranslateY() + SK_Scalar1);
}
void SkPerlinNoiseShaderImpl::PerlinNoiseShaderContext::shadeSpan(
int x, int y, SkPMColor result[], int count) {
SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
StitchData stitchData;
for (int i = 0; i < count; ++i) {
result[i] = shade(point, stitchData);
point.fX += SK_Scalar1;
}
}
/////////////////////////////////////////////////////////////////////
#if SK_SUPPORT_GPU
class GrGLPerlinNoise : public GrGLSLFragmentProcessor {
public:
void emitCode(EmitArgs&) override;
static inline void GenKey(const GrProcessor&, const GrShaderCaps&, GrProcessorKeyBuilder* b);
protected:
void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override;
private:
GrGLSLProgramDataManager::UniformHandle fStitchDataUni;
GrGLSLProgramDataManager::UniformHandle fBaseFrequencyUni;
typedef GrGLSLFragmentProcessor INHERITED;
};
/////////////////////////////////////////////////////////////////////
class GrPerlinNoise2Effect : public GrFragmentProcessor {
public:
static std::unique_ptr<GrFragmentProcessor> Make(
SkPerlinNoiseShaderImpl::Type type, int numOctaves, bool stitchTiles,
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
sk_sp<GrTextureProxy> permutationsProxy, sk_sp<GrTextureProxy> noiseProxy,
const SkMatrix& matrix) {
return std::unique_ptr<GrFragmentProcessor>(new GrPerlinNoise2Effect(
type, numOctaves, stitchTiles, std::move(paintingData),
std::move(permutationsProxy), std::move(noiseProxy), matrix));
}
const char* name() const override { return "PerlinNoise"; }
std::unique_ptr<GrFragmentProcessor> clone() const override {
return std::unique_ptr<GrFragmentProcessor>(new GrPerlinNoise2Effect(*this));
}
const SkPerlinNoiseShaderImpl::StitchData& stitchData() const { return fPaintingData->fStitchDataInit; }
SkPerlinNoiseShaderImpl::Type type() const { return fType; }
bool stitchTiles() const { return fStitchTiles; }
const SkVector& baseFrequency() const { return fPaintingData->fBaseFrequency; }
int numOctaves() const { return fNumOctaves; }
const SkMatrix& matrix() const { return fCoordTransform.getMatrix(); }
private:
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override {
return new GrGLPerlinNoise;
}
virtual void onGetGLSLProcessorKey(const GrShaderCaps& caps,
GrProcessorKeyBuilder* b) const override {
GrGLPerlinNoise::GenKey(*this, caps, b);
}
bool onIsEqual(const GrFragmentProcessor& sBase) const override {
const GrPerlinNoise2Effect& s = sBase.cast<GrPerlinNoise2Effect>();
return fType == s.fType &&
fPaintingData->fBaseFrequency == s.fPaintingData->fBaseFrequency &&
fNumOctaves == s.fNumOctaves &&
fStitchTiles == s.fStitchTiles &&
fPaintingData->fStitchDataInit == s.fPaintingData->fStitchDataInit;
}
GrPerlinNoise2Effect(SkPerlinNoiseShaderImpl::Type type, int numOctaves, bool stitchTiles,
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
sk_sp<GrTextureProxy> permutationsProxy,
sk_sp<GrTextureProxy> noiseProxy,
const SkMatrix& matrix)
: INHERITED(kGrPerlinNoise2Effect_ClassID, kNone_OptimizationFlags)
, fType(type)
, fNumOctaves(numOctaves)
, fStitchTiles(stitchTiles)
, fPermutationsSampler(std::move(permutationsProxy))
, fNoiseSampler(std::move(noiseProxy))
, fPaintingData(std::move(paintingData)) {
this->addTextureSampler(&fPermutationsSampler);
this->addTextureSampler(&fNoiseSampler);
fCoordTransform.reset(matrix);
this->addCoordTransform(&fCoordTransform);
}
GrPerlinNoise2Effect(const GrPerlinNoise2Effect& that)
: INHERITED(kGrPerlinNoise2Effect_ClassID, kNone_OptimizationFlags)
, fType(that.fType)
, fCoordTransform(that.fCoordTransform)
, fNumOctaves(that.fNumOctaves)
, fStitchTiles(that.fStitchTiles)
, fPermutationsSampler(that.fPermutationsSampler)
, fNoiseSampler(that.fNoiseSampler)
, fPaintingData(new SkPerlinNoiseShaderImpl::PaintingData(*that.fPaintingData)) {
this->addTextureSampler(&fPermutationsSampler);
this->addTextureSampler(&fNoiseSampler);
this->addCoordTransform(&fCoordTransform);
}
GR_DECLARE_FRAGMENT_PROCESSOR_TEST
SkPerlinNoiseShaderImpl::Type fType;
GrCoordTransform fCoordTransform;
int fNumOctaves;
bool fStitchTiles;
TextureSampler fPermutationsSampler;
TextureSampler fNoiseSampler;
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> fPaintingData;
typedef GrFragmentProcessor INHERITED;
};
/////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrPerlinNoise2Effect);
#if GR_TEST_UTILS
std::unique_ptr<GrFragmentProcessor> GrPerlinNoise2Effect::TestCreate(GrProcessorTestData* d) {
int numOctaves = d->fRandom->nextRangeU(2, 10);
bool stitchTiles = d->fRandom->nextBool();
SkScalar seed = SkIntToScalar(d->fRandom->nextU());
SkISize tileSize = SkISize::Make(d->fRandom->nextRangeU(4, 4096),
d->fRandom->nextRangeU(4, 4096));
SkScalar baseFrequencyX = d->fRandom->nextRangeScalar(0.01f,
0.99f);
SkScalar baseFrequencyY = d->fRandom->nextRangeScalar(0.01f,
0.99f);
sk_sp<SkShader> shader(d->fRandom->nextBool() ?
SkPerlinNoiseShader::MakeFractalNoise(baseFrequencyX, baseFrequencyY, numOctaves, seed,
stitchTiles ? &tileSize : nullptr) :
SkPerlinNoiseShader::MakeTurbulence(baseFrequencyX, baseFrequencyY, numOctaves, seed,
stitchTiles ? &tileSize : nullptr));
GrTest::TestAsFPArgs asFPArgs(d);
return as_SB(shader)->asFragmentProcessor(asFPArgs.args());
}
#endif
void GrGLPerlinNoise::emitCode(EmitArgs& args) {
const GrPerlinNoise2Effect& pne = args.fFp.cast<GrPerlinNoise2Effect>();
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
SkString vCoords = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);
fBaseFrequencyUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
"baseFrequency");
const char* baseFrequencyUni = uniformHandler->getUniformCStr(fBaseFrequencyUni);
const char* stitchDataUni = nullptr;
if (pne.stitchTiles()) {
fStitchDataUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
"stitchData");
stitchDataUni = uniformHandler->getUniformCStr(fStitchDataUni);
}
// There are 4 lines, so the center of each line is 1/8, 3/8, 5/8 and 7/8
const char* chanCoordR = "0.125";
const char* chanCoordG = "0.375";
const char* chanCoordB = "0.625";
const char* chanCoordA = "0.875";
const char* chanCoord = "chanCoord";
const char* stitchData = "stitchData";
const char* ratio = "ratio";
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
// [-1,1] vector and perform a dot product between that vector and the provided vector.
const char* dotLattice = "dot(((%s.ga + %s.rb * half2(%s)) * half2(2.0) - half2(1.0)), %s);";
// Add noise function
static const GrShaderVar gPerlinNoiseArgs[] = {
GrShaderVar(chanCoord, kHalf_GrSLType),
GrShaderVar(noiseVec, kHalf2_GrSLType)
};
static const GrShaderVar gPerlinNoiseStitchArgs[] = {
GrShaderVar(chanCoord, kHalf_GrSLType),
GrShaderVar(noiseVec, kHalf2_GrSLType),
GrShaderVar(stitchData, kHalf2_GrSLType)
};
SkString noiseCode;
noiseCode.appendf("\thalf4 %s;\n", floorVal);
noiseCode.appendf("\t%s.xy = floor(%s);\n", floorVal, noiseVec);
noiseCode.appendf("\t%s.zw = %s.xy + half2(1.0);\n", floorVal, floorVal);
noiseCode.appendf("\thalf2 %s = fract(%s);\n", fractVal, noiseVec);
// smooth curve : t * t * (3 - 2 * t)
noiseCode.appendf("\n\thalf2 %s = %s * %s * (half2(3.0) - half2(2.0) * %s);",
noiseSmooth, fractVal, fractVal, fractVal);
// Adjust frequencies if we're stitching tiles
if (pne.stitchTiles()) {
noiseCode.appendf("\n\tif(%s.x >= %s.x) { %s.x -= %s.x; }",
floorVal, stitchData, floorVal, stitchData);
noiseCode.appendf("\n\tif(%s.y >= %s.y) { %s.y -= %s.y; }",
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 = fract(floor(mod(%s, 256.0)) / half4(256.0));\n",
floorVal, floorVal);
// Get permutation for x
{
SkString xCoords("");
xCoords.appendf("half2(%s.x, 0.5)", floorVal);
noiseCode.appendf("\n\thalf2 %s;\n\t%s.x = ", latticeIdx, latticeIdx);
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[0], xCoords.c_str(),
kHalf2_GrSLType);
noiseCode.append(".r;");
}
// Get permutation for x + 1
{
SkString xCoords("");
xCoords.appendf("half2(%s.z, 0.5)", floorVal);
noiseCode.appendf("\n\t%s.y = ", latticeIdx);
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[0], xCoords.c_str(),
kHalf2_GrSLType);
noiseCode.append(".r;");
}
#if defined(SK_BUILD_FOR_ANDROID)
// Android rounding for Tegra devices, like, for example: Xoom (Tegra 2), Nexus 7 (Tegra 3).
// The issue is that colors aren't accurate enough on Tegra devices. For example, if an 8 bit
// value of 124 (or 0.486275 here) is entered, we can get a texture value of 123.513725
// (or 0.484368 here). The following rounding operation prevents these precision issues from
// affecting the result of the noise by making sure that we only have multiples of 1/255.
// (Note that 1/255 is about 0.003921569, which is the value used here).
noiseCode.appendf("\n\t%s = floor(%s * half2(255.0) + half2(0.5)) * half2(0.003921569);",
latticeIdx, latticeIdx);
#endif
// Get (x,y) coordinates with the permutated x
noiseCode.appendf("\n\thalf4 %s = fract(%s.xyxy + %s.yyww);", bcoords, latticeIdx, floorVal);
noiseCode.appendf("\n\n\thalf2 %s;", uv);
// Compute u, at offset (0,0)
{
SkString latticeCoords("");
latticeCoords.appendf("half2(%s.x, %s)", bcoords, chanCoord);
noiseCode.appendf("\n\thalf4 %s = ", lattice);
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[1], latticeCoords.c_str(),
kHalf2_GrSLType);
noiseCode.appendf(".bgra;\n\t%s.x = ", uv);
noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
}
noiseCode.appendf("\n\t%s.x -= 1.0;", fractVal);
// Compute v, at offset (-1,0)
{
SkString latticeCoords("");
latticeCoords.appendf("half2(%s.y, %s)", bcoords, chanCoord);
noiseCode.append("\n\tlattice = ");
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[1], latticeCoords.c_str(),
kHalf2_GrSLType);
noiseCode.appendf(".bgra;\n\t%s.y = ", uv);
noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
}
// Compute 'a' as a linear interpolation of 'u' and 'v'
noiseCode.appendf("\n\thalf2 %s;", ab);
noiseCode.appendf("\n\t%s.x = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth);
noiseCode.appendf("\n\t%s.y -= 1.0;", fractVal);
// Compute v, at offset (-1,-1)
{
SkString latticeCoords("");
latticeCoords.appendf("half2(%s.w, %s)", bcoords, chanCoord);
noiseCode.append("\n\tlattice = ");
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[1], latticeCoords.c_str(),
kHalf2_GrSLType);
noiseCode.appendf(".bgra;\n\t%s.y = ", uv);
noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
}
noiseCode.appendf("\n\t%s.x += 1.0;", fractVal);
// Compute u, at offset (0,-1)
{
SkString latticeCoords("");
latticeCoords.appendf("half2(%s.z, %s)", bcoords, chanCoord);
noiseCode.append("\n\tlattice = ");
fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[1], latticeCoords.c_str(),
kHalf2_GrSLType);
noiseCode.appendf(".bgra;\n\t%s.x = ", uv);
noiseCode.appendf(dotLattice, lattice, lattice, inc8bit, fractVal);
}
// Compute 'b' as a linear interpolation of 'u' and 'v'
noiseCode.appendf("\n\t%s.y = mix(%s.x, %s.y, %s.x);", ab, uv, uv, noiseSmooth);
// Compute the noise as a linear interpolation of 'a' and 'b'
noiseCode.appendf("\n\treturn mix(%s.x, %s.y, %s.y);\n", ab, ab, noiseSmooth);
SkString noiseFuncName;
if (pne.stitchTiles()) {
fragBuilder->emitFunction(kHalf_GrSLType,
"perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseStitchArgs),
gPerlinNoiseStitchArgs, noiseCode.c_str(), &noiseFuncName);
} else {
fragBuilder->emitFunction(kHalf_GrSLType,
"perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseArgs),
gPerlinNoiseArgs, noiseCode.c_str(), &noiseFuncName);
}
// There are rounding errors if the floor operation is not performed here
fragBuilder->codeAppendf("\n\t\thalf2 %s = floor(%s.xy) * %s;",
noiseVec, vCoords.c_str(), baseFrequencyUni);
// Clear the color accumulator
fragBuilder->codeAppendf("\n\t\t%s = half4(0.0);", args.fOutputColor);
if (pne.stitchTiles()) {
// Set up TurbulenceInitial stitch values.
fragBuilder->codeAppendf("\n\t\thalf2 %s = %s;", stitchData, stitchDataUni);
}
fragBuilder->codeAppendf("\n\t\thalf %s = 1.0;", ratio);
// Loop over all octaves
fragBuilder->codeAppendf("for (int octave = 0; octave < %d; ++octave) {", pne.numOctaves());
fragBuilder->codeAppendf("\n\t\t\t%s += ", args.fOutputColor);
if (pne.type() != SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
fragBuilder->codeAppend("abs(");
}
if (pne.stitchTiles()) {
fragBuilder->codeAppendf(
"half4(\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s),"
"\n\t\t\t\t%s(%s, %s, %s),\n\t\t\t\t%s(%s, %s, %s))",
noiseFuncName.c_str(), chanCoordR, noiseVec, stitchData,
noiseFuncName.c_str(), chanCoordG, noiseVec, stitchData,
noiseFuncName.c_str(), chanCoordB, noiseVec, stitchData,
noiseFuncName.c_str(), chanCoordA, noiseVec, stitchData);
} else {
fragBuilder->codeAppendf(
"half4(\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s),"
"\n\t\t\t\t%s(%s, %s),\n\t\t\t\t%s(%s, %s))",
noiseFuncName.c_str(), chanCoordR, noiseVec,
noiseFuncName.c_str(), chanCoordG, noiseVec,
noiseFuncName.c_str(), chanCoordB, noiseVec,
noiseFuncName.c_str(), chanCoordA, noiseVec);
}
if (pne.type() != SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
fragBuilder->codeAppendf(")"); // end of "abs("
}
fragBuilder->codeAppendf(" * %s;", ratio);
fragBuilder->codeAppendf("\n\t\t\t%s *= half2(2.0);", noiseVec);
fragBuilder->codeAppendf("\n\t\t\t%s *= 0.5;", ratio);
if (pne.stitchTiles()) {
fragBuilder->codeAppendf("\n\t\t\t%s *= half2(2.0);", stitchData);
}
fragBuilder->codeAppend("\n\t\t}"); // end of the for loop on octaves
if (pne.type() == SkPerlinNoiseShaderImpl::kFractalNoise_Type) {
// The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
// by fractalNoise and (turbulenceFunctionResult) by turbulence.
fragBuilder->codeAppendf("\n\t\t%s = %s * half4(0.5) + half4(0.5);",
args.fOutputColor,args.fOutputColor);
}
// Clamp values
fragBuilder->codeAppendf("\n\t\t%s = clamp(%s, 0.0, 1.0);", args.fOutputColor, args.fOutputColor);
// Pre-multiply the result
fragBuilder->codeAppendf("\n\t\t%s = half4(%s.rgb * %s.aaa, %s.a);\n",
args.fOutputColor, args.fOutputColor,
args.fOutputColor, args.fOutputColor);
}
void GrGLPerlinNoise::GenKey(const GrProcessor& processor, const GrShaderCaps&,
GrProcessorKeyBuilder* b) {
const GrPerlinNoise2Effect& turbulence = processor.cast<GrPerlinNoise2Effect>();
uint32_t key = turbulence.numOctaves();
key = key << 3; // Make room for next 3 bits
switch (turbulence.type()) {
case SkPerlinNoiseShaderImpl::kFractalNoise_Type:
key |= 0x1;
break;
case SkPerlinNoiseShaderImpl::kTurbulence_Type:
key |= 0x2;
break;
default:
// leave key at 0
break;
}
if (turbulence.stitchTiles()) {
key |= 0x4; // Flip the 3rd bit if tile stitching is on
}
b->add32(key);
}
void GrGLPerlinNoise::onSetData(const GrGLSLProgramDataManager& pdman,
const GrFragmentProcessor& processor) {
INHERITED::onSetData(pdman, processor);
const GrPerlinNoise2Effect& turbulence = processor.cast<GrPerlinNoise2Effect>();
const SkVector& baseFrequency = turbulence.baseFrequency();
pdman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY);
if (turbulence.stitchTiles()) {
const SkPerlinNoiseShaderImpl::StitchData& stitchData = turbulence.stitchData();
pdman.set2f(fStitchDataUni, SkIntToScalar(stitchData.fWidth),
SkIntToScalar(stitchData.fHeight));
}
}
/////////////////////////////////////////////////////////////////////
class GrGLImprovedPerlinNoise : public GrGLSLFragmentProcessor {
public:
void emitCode(EmitArgs&) override;
static inline void GenKey(const GrProcessor&, const GrShaderCaps&, GrProcessorKeyBuilder*);
protected:
void onSetData(const GrGLSLProgramDataManager&, const GrFragmentProcessor&) override;
private:
GrGLSLProgramDataManager::UniformHandle fZUni;
GrGLSLProgramDataManager::UniformHandle fBaseFrequencyUni;
typedef GrGLSLFragmentProcessor INHERITED;
};
/////////////////////////////////////////////////////////////////////
class GrImprovedPerlinNoiseEffect : public GrFragmentProcessor {
public:
static std::unique_ptr<GrFragmentProcessor> Make(
int octaves, SkScalar z,
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
sk_sp<GrTextureProxy> permutationsProxy, sk_sp<GrTextureProxy> gradientProxy,
const SkMatrix& matrix) {
return std::unique_ptr<GrFragmentProcessor>(new GrImprovedPerlinNoiseEffect(
octaves, z, std::move(paintingData), std::move(permutationsProxy),
std::move(gradientProxy), matrix));
}
const char* name() const override { return "ImprovedPerlinNoise"; }
std::unique_ptr<GrFragmentProcessor> clone() const override {
return std::unique_ptr<GrFragmentProcessor>(new GrImprovedPerlinNoiseEffect(*this));
}
const SkVector& baseFrequency() const { return fPaintingData->fBaseFrequency; }
SkScalar z() const { return fZ; }
int octaves() const { return fOctaves; }
const SkMatrix& matrix() const { return fCoordTransform.getMatrix(); }
private:
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override {
return new GrGLImprovedPerlinNoise;
}
void onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override {
GrGLImprovedPerlinNoise::GenKey(*this, caps, b);
}
bool onIsEqual(const GrFragmentProcessor& sBase) const override {
const GrImprovedPerlinNoiseEffect& s = sBase.cast<GrImprovedPerlinNoiseEffect>();
return fZ == fZ &&
fPaintingData->fBaseFrequency == s.fPaintingData->fBaseFrequency;
}
GrImprovedPerlinNoiseEffect(int octaves, SkScalar z,
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData,
sk_sp<GrTextureProxy> permutationsProxy,
sk_sp<GrTextureProxy> gradientProxy,
const SkMatrix& matrix)
: INHERITED(kGrImprovedPerlinNoiseEffect_ClassID, kNone_OptimizationFlags)
, fOctaves(octaves)
, fZ(z)
, fPermutationsSampler(std::move(permutationsProxy))
, fGradientSampler(std::move(gradientProxy))
, fPaintingData(std::move(paintingData)) {
this->addTextureSampler(&fPermutationsSampler);
this->addTextureSampler(&fGradientSampler);
fCoordTransform.reset(matrix);
this->addCoordTransform(&fCoordTransform);
}
GrImprovedPerlinNoiseEffect(const GrImprovedPerlinNoiseEffect& that)
: INHERITED(kGrImprovedPerlinNoiseEffect_ClassID, kNone_OptimizationFlags)
, fCoordTransform(that.fCoordTransform)
, fOctaves(that.fOctaves)
, fZ(that.fZ)
, fPermutationsSampler(that.fPermutationsSampler)
, fGradientSampler(that.fGradientSampler)
, fPaintingData(new SkPerlinNoiseShaderImpl::PaintingData(*that.fPaintingData)) {
this->addTextureSampler(&fPermutationsSampler);
this->addTextureSampler(&fGradientSampler);
this->addCoordTransform(&fCoordTransform);
}
GR_DECLARE_FRAGMENT_PROCESSOR_TEST
GrCoordTransform fCoordTransform;
int fOctaves;
SkScalar fZ;
TextureSampler fPermutationsSampler;
TextureSampler fGradientSampler;
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> fPaintingData;
typedef GrFragmentProcessor INHERITED;
};
/////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrImprovedPerlinNoiseEffect);
#if GR_TEST_UTILS
std::unique_ptr<GrFragmentProcessor> GrImprovedPerlinNoiseEffect::TestCreate(
GrProcessorTestData* d) {
SkScalar baseFrequencyX = d->fRandom->nextRangeScalar(0.01f,
0.99f);
SkScalar baseFrequencyY = d->fRandom->nextRangeScalar(0.01f,
0.99f);
int numOctaves = d->fRandom->nextRangeU(2, 10);
SkScalar z = SkIntToScalar(d->fRandom->nextU());
sk_sp<SkShader> shader(SkPerlinNoiseShader::MakeImprovedNoise(baseFrequencyX,
baseFrequencyY,
numOctaves,
z));
GrTest::TestAsFPArgs asFPArgs(d);
return as_SB(shader)->asFragmentProcessor(asFPArgs.args());
}
#endif
void GrGLImprovedPerlinNoise::emitCode(EmitArgs& args) {
const GrImprovedPerlinNoiseEffect& pne = args.fFp.cast<GrImprovedPerlinNoiseEffect>();
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
SkString vCoords = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);
fBaseFrequencyUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf2_GrSLType,
"baseFrequency");
const char* baseFrequencyUni = uniformHandler->getUniformCStr(fBaseFrequencyUni);
fZUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf_GrSLType, "z");
const char* zUni = uniformHandler->getUniformCStr(fZUni);
// fade function
static const GrShaderVar fadeArgs[] = {
GrShaderVar("t", kHalf3_GrSLType)
};
SkString fadeFuncName;
fragBuilder->emitFunction(kHalf3_GrSLType, "fade", SK_ARRAY_COUNT(fadeArgs),
fadeArgs,
"return t * t * t * (t * (t * 6.0 - 15.0) + 10.0);",
&fadeFuncName);
// perm function
static const GrShaderVar permArgs[] = {
GrShaderVar("x", kHalf_GrSLType)
};
SkString permFuncName;
SkString permCode("return ");
// FIXME even though I'm creating these textures with kRepeat_TileMode, they're clamped. Not
// sure why. Using fract() (here and the next texture lookup) as a workaround.
fragBuilder->appendTextureLookup(&permCode, args.fTexSamplers[0], "float2(fract(x / 256.0), 0.0)",
kHalf2_GrSLType);
permCode.append(".r * 255.0;");
fragBuilder->emitFunction(kHalf_GrSLType, "perm", SK_ARRAY_COUNT(permArgs), permArgs,
permCode.c_str(), &permFuncName);
// grad function
static const GrShaderVar gradArgs[] = {
GrShaderVar("x", kHalf_GrSLType),
GrShaderVar("p", kHalf3_GrSLType)
};
SkString gradFuncName;
SkString gradCode("return dot(");
fragBuilder->appendTextureLookup(&gradCode, args.fTexSamplers[1], "float2(fract(x / 16.0), 0.0)",
kHalf2_GrSLType);
gradCode.append(".rgb * 255.0 - float3(1.0), p);");
fragBuilder->emitFunction(kHalf_GrSLType, "grad", SK_ARRAY_COUNT(gradArgs), gradArgs,
gradCode.c_str(), &gradFuncName);
// lerp function
static const GrShaderVar lerpArgs[] = {
GrShaderVar("a", kHalf_GrSLType),
GrShaderVar("b", kHalf_GrSLType),
GrShaderVar("w", kHalf_GrSLType)
};
SkString lerpFuncName;
fragBuilder->emitFunction(kHalf_GrSLType, "lerp", SK_ARRAY_COUNT(lerpArgs), lerpArgs,
"return a + w * (b - a);", &lerpFuncName);
// noise function
static const GrShaderVar noiseArgs[] = {
GrShaderVar("p", kHalf3_GrSLType),
};
SkString noiseFuncName;
SkString noiseCode;
noiseCode.append("half3 P = mod(floor(p), 256.0);");
noiseCode.append("p -= floor(p);");
noiseCode.appendf("half3 f = %s(p);", fadeFuncName.c_str());
noiseCode.appendf("half A = %s(P.x) + P.y;", permFuncName.c_str());
noiseCode.appendf("half AA = %s(A) + P.z;", permFuncName.c_str());
noiseCode.appendf("half AB = %s(A + 1.0) + P.z;", permFuncName.c_str());
noiseCode.appendf("half B = %s(P.x + 1.0) + P.y;", permFuncName.c_str());
noiseCode.appendf("half BA = %s(B) + P.z;", permFuncName.c_str());
noiseCode.appendf("half BB = %s(B + 1.0) + P.z;", permFuncName.c_str());
noiseCode.appendf("half result = %s(", lerpFuncName.c_str());
noiseCode.appendf("%s(%s(%s(%s(AA), p),", lerpFuncName.c_str(), lerpFuncName.c_str(),
gradFuncName.c_str(), permFuncName.c_str());
noiseCode.appendf("%s(%s(BA), p + half3(-1.0, 0.0, 0.0)), f.x),", gradFuncName.c_str(),
permFuncName.c_str());
noiseCode.appendf("%s(%s(%s(AB), p + half3(0.0, -1.0, 0.0)),", lerpFuncName.c_str(),
gradFuncName.c_str(), permFuncName.c_str());
noiseCode.appendf("%s(%s(BB), p + half3(-1.0, -1.0, 0.0)), f.x), f.y),",
gradFuncName.c_str(), permFuncName.c_str());
noiseCode.appendf("%s(%s(%s(%s(AA + 1.0), p + half3(0.0, 0.0, -1.0)),",
lerpFuncName.c_str(), lerpFuncName.c_str(), gradFuncName.c_str(),
permFuncName.c_str());
noiseCode.appendf("%s(%s(BA + 1.0), p + half3(-1.0, 0.0, -1.0)), f.x),",
gradFuncName.c_str(), permFuncName.c_str());
noiseCode.appendf("%s(%s(%s(AB + 1.0), p + half3(0.0, -1.0, -1.0)),",
lerpFuncName.c_str(), gradFuncName.c_str(), permFuncName.c_str());
noiseCode.appendf("%s(%s(BB + 1.0), p + half3(-1.0, -1.0, -1.0)), f.x), f.y), f.z);",
gradFuncName.c_str(), permFuncName.c_str());
noiseCode.append("return result;");
fragBuilder->emitFunction(kHalf_GrSLType, "noise", SK_ARRAY_COUNT(noiseArgs), noiseArgs,
noiseCode.c_str(), &noiseFuncName);
// noiseOctaves function
static const GrShaderVar noiseOctavesArgs[] = {
GrShaderVar("p", kHalf3_GrSLType)
};
SkString noiseOctavesFuncName;
SkString noiseOctavesCode;
noiseOctavesCode.append("half result = 0.0;");
noiseOctavesCode.append("half ratio = 1.0;");
noiseOctavesCode.appendf("for (half i = 0.0; i < %d; i++) {", pne.octaves());
noiseOctavesCode.appendf("result += %s(p) / ratio;", noiseFuncName.c_str());
noiseOctavesCode.append("p *= 2.0;");
noiseOctavesCode.append("ratio *= 2.0;");
noiseOctavesCode.append("}");
noiseOctavesCode.append("return (result + 1.0) / 2.0;");
fragBuilder->emitFunction(kHalf_GrSLType, "noiseOctaves", SK_ARRAY_COUNT(noiseOctavesArgs),
noiseOctavesArgs, noiseOctavesCode.c_str(), &noiseOctavesFuncName);
fragBuilder->codeAppendf("half2 coords = %s * %s;", vCoords.c_str(), baseFrequencyUni);
fragBuilder->codeAppendf("half r = %s(half3(coords, %s));", noiseOctavesFuncName.c_str(),
zUni);
fragBuilder->codeAppendf("half g = %s(half3(coords, %s + 0000.0));",
noiseOctavesFuncName.c_str(), zUni);
fragBuilder->codeAppendf("half b = %s(half3(coords, %s + 0000.0));",
noiseOctavesFuncName.c_str(), zUni);
fragBuilder->codeAppendf("half a = %s(half3(coords, %s + 0000.0));",
noiseOctavesFuncName.c_str(), zUni);
fragBuilder->codeAppendf("%s = half4(r, g, b, a);", args.fOutputColor);
// Clamp values
fragBuilder->codeAppendf("%s = clamp(%s, 0.0, 1.0);", args.fOutputColor, args.fOutputColor);
// Pre-multiply the result
fragBuilder->codeAppendf("\n\t\t%s = half4(%s.rgb * %s.aaa, %s.a);\n",
args.fOutputColor, args.fOutputColor,
args.fOutputColor, args.fOutputColor);
}
void GrGLImprovedPerlinNoise::GenKey(const GrProcessor& processor, const GrShaderCaps&,
GrProcessorKeyBuilder* b) {
const GrImprovedPerlinNoiseEffect& pne = processor.cast<GrImprovedPerlinNoiseEffect>();
b->add32(pne.octaves());
}
void GrGLImprovedPerlinNoise::onSetData(const GrGLSLProgramDataManager& pdman,
const GrFragmentProcessor& processor) {
INHERITED::onSetData(pdman, processor);
const GrImprovedPerlinNoiseEffect& noise = processor.cast<GrImprovedPerlinNoiseEffect>();
const SkVector& baseFrequency = noise.baseFrequency();
pdman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY);
pdman.set1f(fZUni, noise.z());
}
/////////////////////////////////////////////////////////////////////
std::unique_ptr<GrFragmentProcessor> SkPerlinNoiseShaderImpl::asFragmentProcessor(
const GrFPArgs& args) const {
SkASSERT(args.fContext);
SkMatrix localMatrix = this->getLocalMatrix();
if (args.fLocalMatrix) {
localMatrix.preConcat(*args.fLocalMatrix);
}
SkMatrix matrix = *args.fViewMatrix;
matrix.preConcat(localMatrix);
// Either we don't stitch tiles, either we have a valid tile size
SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
std::unique_ptr<SkPerlinNoiseShaderImpl::PaintingData> paintingData =
skstd::make_unique<SkPerlinNoiseShaderImpl::PaintingData>(fTileSize,
fSeed,
fBaseFrequencyX,
fBaseFrequencyY,
matrix);
SkMatrix m = *args.fViewMatrix;
m.setTranslateX(-localMatrix.getTranslateX() + SK_Scalar1);
m.setTranslateY(-localMatrix.getTranslateY() + SK_Scalar1);
auto proxyProvider = args.fContext->contextPriv().proxyProvider();
if (fType == kImprovedNoise_Type) {
// Need to assert that the textures we'll create are power of 2 so a copy isn't needed.
// We also know that we will not be using mipmaps. If things things weren't true we should
// go through GrBitmapTextureMaker to handle needed copies.
const sk_sp<SkImage> permutationsImage = paintingData->getImprovedPermutationsImage();
SkASSERT(SkIsPow2(permutationsImage->width()) && SkIsPow2(permutationsImage->height()));
sk_sp<GrTextureProxy> permutationsTexture(
GrMakeCachedImageProxy(proxyProvider, std::move(permutationsImage)));
const sk_sp<SkImage> gradientImage = paintingData->getGradientImage();
SkASSERT(SkIsPow2(gradientImage->width()) && SkIsPow2(gradientImage->height()));
sk_sp<GrTextureProxy> gradientTexture(
GrMakeCachedImageProxy(proxyProvider, std::move(gradientImage)));
return GrImprovedPerlinNoiseEffect::Make(fNumOctaves, fSeed, std::move(paintingData),
std::move(permutationsTexture),
std::move(gradientTexture), m);
}
if (0 == fNumOctaves) {
if (kFractalNoise_Type == fType) {
// Extract the incoming alpha and emit rgba = (a/4, a/4, a/4, a/2)
// TODO: Either treat the output of this shader as sRGB or allow client to specify a
// color space of the noise. Either way, this case (and the GLSL) need to convert to
// the destination.
auto inner =
GrConstColorProcessor::Make(GrColor4f::FromGrColor(0x80404040),
GrConstColorProcessor::InputMode::kModulateRGBA);
return GrFragmentProcessor::MulChildByInputAlpha(std::move(inner));
}
// Emit zero.
return GrConstColorProcessor::Make(GrColor4f::TransparentBlack(),
GrConstColorProcessor::InputMode::kIgnore);
}
// Need to assert that the textures we'll create are power of 2 so that now copy is needed. We
// also know that we will not be using mipmaps. If things things weren't true we should go
// through GrBitmapTextureMaker to handle needed copies.
const sk_sp<SkImage> permutationsImage = paintingData->getPermutationsImage();
SkASSERT(SkIsPow2(permutationsImage->width()) && SkIsPow2(permutationsImage->height()));
sk_sp<GrTextureProxy> permutationsProxy = GrMakeCachedImageProxy(proxyProvider,
std::move(permutationsImage));
const sk_sp<SkImage> noiseImage = paintingData->getNoiseImage();
SkASSERT(SkIsPow2(noiseImage->width()) && SkIsPow2(noiseImage->height()));
sk_sp<GrTextureProxy> noiseProxy = GrMakeCachedImageProxy(proxyProvider,
std::move(noiseImage));
if (permutationsProxy && noiseProxy) {
auto inner = GrPerlinNoise2Effect::Make(fType,
fNumOctaves,
fStitchTiles,
std::move(paintingData),
std::move(permutationsProxy),
std::move(noiseProxy),
m);
return GrFragmentProcessor::MulChildByInputAlpha(std::move(inner));
}
return nullptr;
}
#endif
#ifndef SK_IGNORE_TO_STRING
void SkPerlinNoiseShaderImpl::toString(SkString* str) const {
str->append("SkPerlinNoiseShaderImpl: (");
str->append("type: ");
switch (fType) {
case kFractalNoise_Type:
str->append("\"fractal noise\"");
break;
case kTurbulence_Type:
str->append("\"turbulence\"");
break;
default:
str->append("\"unknown\"");
break;
}
str->append(" base frequency: (");
str->appendScalar(fBaseFrequencyX);
str->append(", ");
str->appendScalar(fBaseFrequencyY);
str->append(") number of octaves: ");
str->appendS32(fNumOctaves);
str->append(" seed: ");
str->appendScalar(fSeed);
str->append(" stitch tiles: ");
str->append(fStitchTiles ? "true " : "false ");
this->INHERITED::toString(str);
str->append(")");
}
#endif
///////////////////////////////////////////////////////////////////////////////////////////////////
sk_sp<SkShader> SkPerlinNoiseShader::MakeFractalNoise(SkScalar baseFrequencyX,
SkScalar baseFrequencyY,
int numOctaves, SkScalar seed,
const SkISize* tileSize) {
return sk_sp<SkShader>(new SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::kFractalNoise_Type,
baseFrequencyX, baseFrequencyY, numOctaves, seed,
tileSize));
}
sk_sp<SkShader> SkPerlinNoiseShader::MakeTurbulence(SkScalar baseFrequencyX,
SkScalar baseFrequencyY,
int numOctaves, SkScalar seed,
const SkISize* tileSize) {
return sk_sp<SkShader>(new SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::kTurbulence_Type,
baseFrequencyX, baseFrequencyY, numOctaves, seed,
tileSize));
}
sk_sp<SkShader> SkPerlinNoiseShader::MakeImprovedNoise(SkScalar baseFrequencyX,
SkScalar baseFrequencyY,
int numOctaves, SkScalar z) {
return sk_sp<SkShader>(new SkPerlinNoiseShaderImpl(SkPerlinNoiseShaderImpl::kImprovedNoise_Type,
baseFrequencyX, baseFrequencyY, numOctaves, z,
nullptr));
}
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkPerlinNoiseShader)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkPerlinNoiseShaderImpl)
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END