/*
* 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 "SkDither.h"
#include "SkPerlinNoiseShader.h"
#include "SkColorFilter.h"
#include "SkFlattenableBuffers.h"
#include "SkShader.h"
#include "SkUnPreMultiply.h"
#include "SkString.h"
#if SK_SUPPORT_GPU
#include "GrContext.h"
#include "GrCoordTransform.h"
#include "gl/GrGLEffect.h"
#include "GrTBackendEffectFactory.h"
#include "SkGr.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
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;
}
if (noiseValue >= limitValue - 1) {
noiseValue -= newValue - 1;
}
return noiseValue;
}
inline SkScalar smoothCurve(SkScalar t) {
static const SkScalar SK_Scalar3 = 3.0f;
// returns t * t * (3 - 2 * t)
return SkScalarMul(SkScalarSquare(t), SK_Scalar3 - 2 * t);
}
bool perlin_noise_type_is_valid(SkPerlinNoiseShader::Type type) {
return (SkPerlinNoiseShader::kFractalNoise_Type == type) ||
(SkPerlinNoiseShader::kTurbulence_Type == type);
}
} // end namespace
struct SkPerlinNoiseShader::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 SkPerlinNoiseShader::PaintingData {
PaintingData(const SkISize& tileSize)
: fSeed(0)
, fTileSize(tileSize)
, fPermutationsBitmap(NULL)
, fNoiseBitmap(NULL)
{}
~PaintingData()
{
SkDELETE(fPermutationsBitmap);
SkDELETE(fNoiseBitmap);
}
int fSeed;
uint8_t fLatticeSelector[kBlockSize];
uint16_t fNoise[4][kBlockSize][2];
SkPoint fGradient[4][kBlockSize];
SkISize fTileSize;
SkVector fBaseFrequency;
StitchData fStitchDataInit;
private:
SkBitmap* fPermutationsBitmap;
SkBitmap* fNoiseBitmap;
public:
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;
}
void init(SkScalar seed)
{
static const SkScalar gInvBlockSizef = SkScalarInvert(SkIntToScalar(kBlockSize));
// The seed value clamp to the range [1, kRandMaximum - 1].
fSeed = SkScalarRoundToInt(seed);
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(
SkScalarMul(SkIntToScalar(fNoise[channel][i][0] - kBlockSize),
gInvBlockSizef),
SkScalarMul(SkIntToScalar(fNoise[channel][i][1] - kBlockSize),
gInvBlockSizef));
fGradient[channel][i].normalize();
// Put the normalized gradient back into the noise data
fNoise[channel][i][0] = SkScalarRoundToInt(SkScalarMul(
fGradient[channel][i].fX + SK_Scalar1, gHalfMax16bits));
fNoise[channel][i][1] = SkScalarRoundToInt(SkScalarMul(
fGradient[channel][i].fY + SK_Scalar1, gHalfMax16bits));
}
}
// Invalidate bitmaps
SkDELETE(fPermutationsBitmap);
fPermutationsBitmap = NULL;
SkDELETE(fNoiseBitmap);
fNoiseBitmap = NULL;
}
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 = SkScalarDiv(
SkScalarMulFloor(tileWidth, fBaseFrequency.fX), tileWidth);
SkScalar highFrequencx = SkScalarDiv(
SkScalarMulCeil(tileWidth, fBaseFrequency.fX), tileWidth);
// BaseFrequency should be non-negative according to the standard.
if (SkScalarDiv(fBaseFrequency.fX, lowFrequencx) <
SkScalarDiv(highFrequencx, fBaseFrequency.fX)) {
fBaseFrequency.fX = lowFrequencx;
} else {
fBaseFrequency.fX = highFrequencx;
}
}
if (fBaseFrequency.fY) {
SkScalar lowFrequency = SkScalarDiv(
SkScalarMulFloor(tileHeight, fBaseFrequency.fY), tileHeight);
SkScalar highFrequency = SkScalarDiv(
SkScalarMulCeil(tileHeight, fBaseFrequency.fY), tileHeight);
if (SkScalarDiv(fBaseFrequency.fY, lowFrequency) <
SkScalarDiv(highFrequency, fBaseFrequency.fY)) {
fBaseFrequency.fY = lowFrequency;
} else {
fBaseFrequency.fY = highFrequency;
}
}
// Set up TurbulenceInitial stitch values.
fStitchDataInit.fWidth =
SkScalarMulRound(tileWidth, fBaseFrequency.fX);
fStitchDataInit.fWrapX = kPerlinNoise + fStitchDataInit.fWidth;
fStitchDataInit.fHeight =
SkScalarMulRound(tileHeight, fBaseFrequency.fY);
fStitchDataInit.fWrapY = kPerlinNoise + fStitchDataInit.fHeight;
}
SkBitmap* getPermutationsBitmap()
{
if (!fPermutationsBitmap) {
fPermutationsBitmap = SkNEW(SkBitmap);
fPermutationsBitmap->setConfig(SkBitmap::kA8_Config, kBlockSize, 1);
fPermutationsBitmap->allocPixels();
uint8_t* bitmapPixels = fPermutationsBitmap->getAddr8(0, 0);
memcpy(bitmapPixels, fLatticeSelector, sizeof(uint8_t) * kBlockSize);
}
return fPermutationsBitmap;
}
SkBitmap* getNoiseBitmap()
{
if (!fNoiseBitmap) {
fNoiseBitmap = SkNEW(SkBitmap);
fNoiseBitmap->setConfig(SkBitmap::kARGB_8888_Config, kBlockSize, 4);
fNoiseBitmap->allocPixels();
uint32_t* bitmapPixels = fNoiseBitmap->getAddr32(0, 0);
memcpy(bitmapPixels, fNoise[0][0], sizeof(uint16_t) * kBlockSize * 4 * 2);
}
return fNoiseBitmap;
}
};
SkShader* SkPerlinNoiseShader::CreateFractalNoise(SkScalar baseFrequencyX, SkScalar baseFrequencyY,
int numOctaves, SkScalar seed,
const SkISize* tileSize) {
return SkNEW_ARGS(SkPerlinNoiseShader, (kFractalNoise_Type, baseFrequencyX, baseFrequencyY,
numOctaves, seed, tileSize));
}
SkShader* SkPerlinNoiseShader::CreateTubulence(SkScalar baseFrequencyX, SkScalar baseFrequencyY,
int numOctaves, SkScalar seed,
const SkISize* tileSize) {
return SkNEW_ARGS(SkPerlinNoiseShader, (kTurbulence_Type, baseFrequencyX, baseFrequencyY,
numOctaves, seed, tileSize));
}
SkPerlinNoiseShader::SkPerlinNoiseShader(SkPerlinNoiseShader::Type type,
SkScalar baseFrequencyX,
SkScalar baseFrequencyY,
int numOctaves,
SkScalar seed,
const SkISize* tileSize)
: fType(type)
, fBaseFrequencyX(baseFrequencyX)
, fBaseFrequencyY(baseFrequencyY)
, fNumOctaves(numOctaves > 255 ? 255 : numOctaves/*[0,255] octaves allowed*/)
, fSeed(seed)
, fStitchTiles((tileSize != NULL) && !tileSize->isEmpty())
, fPaintingData(NULL)
{
SkASSERT(numOctaves >= 0 && numOctaves < 256);
setTileSize(fStitchTiles ? *tileSize : SkISize::Make(0,0));
fMatrix.reset();
}
SkPerlinNoiseShader::SkPerlinNoiseShader(SkFlattenableReadBuffer& buffer) :
INHERITED(buffer), fPaintingData(NULL) {
fType = (SkPerlinNoiseShader::Type) buffer.readInt();
fBaseFrequencyX = buffer.readScalar();
fBaseFrequencyY = buffer.readScalar();
fNumOctaves = buffer.readInt();
fSeed = buffer.readScalar();
fStitchTiles = buffer.readBool();
fTileSize.fWidth = buffer.readInt();
fTileSize.fHeight = buffer.readInt();
setTileSize(fTileSize);
fMatrix.reset();
buffer.validate(perlin_noise_type_is_valid(fType) &&
(fNumOctaves >= 0) && (fNumOctaves <= 255));
}
SkPerlinNoiseShader::~SkPerlinNoiseShader() {
// Safety, should have been done in endContext()
SkDELETE(fPaintingData);
}
void SkPerlinNoiseShader::flatten(SkFlattenableWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writeInt((int) fType);
buffer.writeScalar(fBaseFrequencyX);
buffer.writeScalar(fBaseFrequencyY);
buffer.writeInt(fNumOctaves);
buffer.writeScalar(fSeed);
buffer.writeBool(fStitchTiles);
buffer.writeInt(fTileSize.fWidth);
buffer.writeInt(fTileSize.fHeight);
}
void SkPerlinNoiseShader::initPaint(PaintingData& paintingData)
{
paintingData.init(fSeed);
// Set frequencies to original values
paintingData.fBaseFrequency.set(fBaseFrequencyX, fBaseFrequencyY);
// Adjust frequecies based on size if stitching is enabled
if (fStitchTiles) {
paintingData.stitch();
}
}
void SkPerlinNoiseShader::setTileSize(const SkISize& tileSize) {
fTileSize = tileSize;
if (NULL == fPaintingData) {
fPaintingData = SkNEW_ARGS(PaintingData, (fTileSize));
initPaint(*fPaintingData);
} else {
// Set Size
fPaintingData->fTileSize = fTileSize;
// Set frequencies to original values
fPaintingData->fBaseFrequency.set(fBaseFrequencyX, fBaseFrequencyY);
// Adjust frequecies based on size if stitching is enabled
if (fStitchTiles) {
fPaintingData->stitch();
}
}
}
SkScalar SkPerlinNoiseShader::noise2D(int channel, const PaintingData& paintingData,
const StitchData& stitchData, const SkPoint& noiseVector)
{
struct Noise {
int noisePositionIntegerValue;
SkScalar noisePositionFractionValue;
Noise(SkScalar component)
{
SkScalar position = component + kPerlinNoise;
noisePositionIntegerValue = SkScalarFloorToInt(position);
noisePositionFractionValue = position - SkIntToScalar(noisePositionIntegerValue);
}
};
Noise noiseX(noiseVector.x());
Noise noiseY(noiseVector.y());
SkScalar u, v;
// If stitching, adjust lattice points accordingly.
if (fStitchTiles) {
noiseX.noisePositionIntegerValue =
checkNoise(noiseX.noisePositionIntegerValue, stitchData.fWrapX, stitchData.fWidth);
noiseY.noisePositionIntegerValue =
checkNoise(noiseY.noisePositionIntegerValue, 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;
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);
fractionValue.fX -= SK_Scalar1; // Offset (-1,0)
v = paintingData.fGradient[channel][nextLatticeIndex & kBlockMask].dot(fractionValue);
SkScalar a = SkScalarInterp(u, v, sx);
fractionValue.fY -= SK_Scalar1; // Offset (-1,-1)
v = paintingData.fGradient[channel][(nextLatticeIndex + 1) & kBlockMask].dot(fractionValue);
fractionValue.fX = noiseX.noisePositionFractionValue; // Offset (0,-1)
u = paintingData.fGradient[channel][(latticeIndex + 1) & kBlockMask].dot(fractionValue);
SkScalar b = SkScalarInterp(u, v, sx);
return SkScalarInterp(a, b, sy);
}
SkScalar SkPerlinNoiseShader::calculateTurbulenceValueForPoint(
int channel, const PaintingData& paintingData, StitchData& stitchData, const SkPoint& point)
{
if (fStitchTiles) {
// Set up TurbulenceInitial stitch values.
stitchData = paintingData.fStitchDataInit;
}
SkScalar turbulenceFunctionResult = 0;
SkPoint noiseVector(SkPoint::Make(SkScalarMul(point.x(), paintingData.fBaseFrequency.fX),
SkScalarMul(point.y(), paintingData.fBaseFrequency.fY)));
SkScalar ratio = SK_Scalar1;
for (int octave = 0; octave < fNumOctaves; ++octave) {
SkScalar noise = noise2D(channel, paintingData, stitchData, noiseVector);
turbulenceFunctionResult += SkScalarDiv(
(fType == kFractalNoise_Type) ? noise : SkScalarAbs(noise), ratio);
noiseVector.fX *= 2;
noiseVector.fY *= 2;
ratio *= 2;
if (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 (fType == kFractalNoise_Type) {
turbulenceFunctionResult =
SkScalarMul(turbulenceFunctionResult, SK_ScalarHalf) + SK_ScalarHalf;
}
if (channel == 3) { // Scale alpha by paint value
turbulenceFunctionResult = SkScalarMul(turbulenceFunctionResult,
SkScalarDiv(SkIntToScalar(getPaintAlpha()), SkIntToScalar(255)));
}
// Clamp result
return SkScalarPin(turbulenceFunctionResult, 0, SK_Scalar1);
}
SkPMColor SkPerlinNoiseShader::shade(const SkPoint& point, StitchData& stitchData) {
SkMatrix matrix = fMatrix;
SkMatrix invMatrix;
if (!matrix.invert(&invMatrix)) {
invMatrix.reset();
} else {
invMatrix.postConcat(invMatrix); // Square the matrix
}
// 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.
matrix.postTranslate(SK_Scalar1, SK_Scalar1);
SkPoint newPoint;
matrix.mapPoints(&newPoint, &point, 1);
invMatrix.mapPoints(&newPoint, &newPoint, 1);
newPoint.fX = SkScalarRoundToScalar(newPoint.fX);
newPoint.fY = SkScalarRoundToScalar(newPoint.fY);
U8CPU rgba[4];
for (int channel = 3; channel >= 0; --channel) {
rgba[channel] = SkScalarFloorToInt(255 *
calculateTurbulenceValueForPoint(channel, *fPaintingData, stitchData, newPoint));
}
return SkPreMultiplyARGB(rgba[3], rgba[0], rgba[1], rgba[2]);
}
bool SkPerlinNoiseShader::setContext(const SkBitmap& device, const SkPaint& paint,
const SkMatrix& matrix) {
fMatrix = matrix;
return INHERITED::setContext(device, paint, matrix);
}
void SkPerlinNoiseShader::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;
}
}
void SkPerlinNoiseShader::shadeSpan16(int x, int y, uint16_t result[], int count) {
SkPoint point = SkPoint::Make(SkIntToScalar(x), SkIntToScalar(y));
StitchData stitchData;
DITHER_565_SCAN(y);
for (int i = 0; i < count; ++i) {
unsigned dither = DITHER_VALUE(x);
result[i] = SkDitherRGB32To565(shade(point, stitchData), dither);
DITHER_INC_X(x);
point.fX += SK_Scalar1;
}
}
/////////////////////////////////////////////////////////////////////
#if SK_SUPPORT_GPU
#include "GrTBackendEffectFactory.h"
class GrGLNoise : public GrGLEffect {
public:
GrGLNoise(const GrBackendEffectFactory& factory,
const GrDrawEffect& drawEffect);
virtual ~GrGLNoise() {}
static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
protected:
SkPerlinNoiseShader::Type fType;
bool fStitchTiles;
int fNumOctaves;
GrGLUniformManager::UniformHandle fBaseFrequencyUni;
GrGLUniformManager::UniformHandle fAlphaUni;
GrGLUniformManager::UniformHandle fInvMatrixUni;
private:
typedef GrGLEffect INHERITED;
};
class GrGLPerlinNoise : public GrGLNoise {
public:
GrGLPerlinNoise(const GrBackendEffectFactory& factory,
const GrDrawEffect& drawEffect)
: GrGLNoise(factory, drawEffect) {}
virtual ~GrGLPerlinNoise() {}
virtual void emitCode(GrGLShaderBuilder*,
const GrDrawEffect&,
EffectKey,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray&) SK_OVERRIDE;
virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
private:
GrGLUniformManager::UniformHandle fStitchDataUni;
typedef GrGLNoise INHERITED;
};
class GrGLSimplexNoise : public GrGLNoise {
// Note : This is for reference only. GrGLPerlinNoise is used for processing.
public:
GrGLSimplexNoise(const GrBackendEffectFactory& factory,
const GrDrawEffect& drawEffect)
: GrGLNoise(factory, drawEffect) {}
virtual ~GrGLSimplexNoise() {}
virtual void emitCode(GrGLShaderBuilder*,
const GrDrawEffect&,
EffectKey,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray&) SK_OVERRIDE;
virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
private:
GrGLUniformManager::UniformHandle fSeedUni;
typedef GrGLNoise INHERITED;
};
/////////////////////////////////////////////////////////////////////
class GrNoiseEffect : public GrEffect {
public:
virtual ~GrNoiseEffect() { }
SkPerlinNoiseShader::Type type() const { return fType; }
bool stitchTiles() const { return fStitchTiles; }
const SkVector& baseFrequency() const { return fBaseFrequency; }
int numOctaves() const { return fNumOctaves; }
const SkMatrix& matrix() const { return fCoordTransform.getMatrix(); }
uint8_t alpha() const { return fAlpha; }
void getConstantColorComponents(GrColor*, uint32_t* validFlags) const SK_OVERRIDE {
*validFlags = 0; // This is noise. Nothing is constant.
}
protected:
virtual bool onIsEqual(const GrEffect& sBase) const SK_OVERRIDE {
const GrNoiseEffect& s = CastEffect<GrNoiseEffect>(sBase);
return fType == s.fType &&
fBaseFrequency == s.fBaseFrequency &&
fNumOctaves == s.fNumOctaves &&
fStitchTiles == s.fStitchTiles &&
fCoordTransform.getMatrix() == s.fCoordTransform.getMatrix() &&
fAlpha == s.fAlpha;
}
GrNoiseEffect(SkPerlinNoiseShader::Type type, const SkVector& baseFrequency, int numOctaves,
bool stitchTiles, const SkMatrix& matrix, uint8_t alpha)
: fType(type)
, fBaseFrequency(baseFrequency)
, fNumOctaves(numOctaves)
, fStitchTiles(stitchTiles)
, fMatrix(matrix)
, fAlpha(alpha) {
// 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 shadeSpan() functions.
SkMatrix m = matrix;
m.postTranslate(SK_Scalar1, SK_Scalar1);
fCoordTransform.reset(kLocal_GrCoordSet, m);
this->addCoordTransform(&fCoordTransform);
this->setWillNotUseInputColor();
}
SkPerlinNoiseShader::Type fType;
GrCoordTransform fCoordTransform;
SkVector fBaseFrequency;
int fNumOctaves;
bool fStitchTiles;
SkMatrix fMatrix;
uint8_t fAlpha;
private:
typedef GrEffect INHERITED;
};
class GrPerlinNoiseEffect : public GrNoiseEffect {
public:
static GrEffectRef* Create(SkPerlinNoiseShader::Type type, const SkVector& baseFrequency,
int numOctaves, bool stitchTiles,
const SkPerlinNoiseShader::StitchData& stitchData,
GrTexture* permutationsTexture, GrTexture* noiseTexture,
const SkMatrix& matrix, uint8_t alpha) {
AutoEffectUnref effect(SkNEW_ARGS(GrPerlinNoiseEffect, (type, baseFrequency, numOctaves,
stitchTiles, stitchData, permutationsTexture, noiseTexture, matrix, alpha)));
return CreateEffectRef(effect);
}
virtual ~GrPerlinNoiseEffect() { }
static const char* Name() { return "PerlinNoise"; }
virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE {
return GrTBackendEffectFactory<GrPerlinNoiseEffect>::getInstance();
}
const SkPerlinNoiseShader::StitchData& stitchData() const { return fStitchData; }
typedef GrGLPerlinNoise GLEffect;
private:
virtual bool onIsEqual(const GrEffect& sBase) const SK_OVERRIDE {
const GrPerlinNoiseEffect& s = CastEffect<GrPerlinNoiseEffect>(sBase);
return INHERITED::onIsEqual(sBase) &&
fPermutationsAccess.getTexture() == s.fPermutationsAccess.getTexture() &&
fNoiseAccess.getTexture() == s.fNoiseAccess.getTexture() &&
fStitchData == s.fStitchData;
}
GrPerlinNoiseEffect(SkPerlinNoiseShader::Type type, const SkVector& baseFrequency,
int numOctaves, bool stitchTiles,
const SkPerlinNoiseShader::StitchData& stitchData,
GrTexture* permutationsTexture, GrTexture* noiseTexture,
const SkMatrix& matrix, uint8_t alpha)
: GrNoiseEffect(type, baseFrequency, numOctaves, stitchTiles, matrix, alpha)
, fPermutationsAccess(permutationsTexture)
, fNoiseAccess(noiseTexture)
, fStitchData(stitchData) {
this->addTextureAccess(&fPermutationsAccess);
this->addTextureAccess(&fNoiseAccess);
}
GR_DECLARE_EFFECT_TEST;
GrTextureAccess fPermutationsAccess;
GrTextureAccess fNoiseAccess;
SkPerlinNoiseShader::StitchData fStitchData;
typedef GrNoiseEffect INHERITED;
};
class GrSimplexNoiseEffect : public GrNoiseEffect {
// Note : This is for reference only. GrPerlinNoiseEffect is used for processing.
public:
static GrEffectRef* Create(SkPerlinNoiseShader::Type type, const SkVector& baseFrequency,
int numOctaves, bool stitchTiles, const SkScalar seed,
const SkMatrix& matrix, uint8_t alpha) {
AutoEffectUnref effect(SkNEW_ARGS(GrSimplexNoiseEffect, (type, baseFrequency, numOctaves,
stitchTiles, seed, matrix, alpha)));
return CreateEffectRef(effect);
}
virtual ~GrSimplexNoiseEffect() { }
static const char* Name() { return "SimplexNoise"; }
virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE {
return GrTBackendEffectFactory<GrSimplexNoiseEffect>::getInstance();
}
const SkScalar& seed() const { return fSeed; }
typedef GrGLSimplexNoise GLEffect;
private:
virtual bool onIsEqual(const GrEffect& sBase) const SK_OVERRIDE {
const GrSimplexNoiseEffect& s = CastEffect<GrSimplexNoiseEffect>(sBase);
return INHERITED::onIsEqual(sBase) && fSeed == s.fSeed;
}
GrSimplexNoiseEffect(SkPerlinNoiseShader::Type type, const SkVector& baseFrequency,
int numOctaves, bool stitchTiles, const SkScalar seed,
const SkMatrix& matrix, uint8_t alpha)
: GrNoiseEffect(type, baseFrequency, numOctaves, stitchTiles, matrix, alpha)
, fSeed(seed) {
}
SkScalar fSeed;
typedef GrNoiseEffect INHERITED;
};
/////////////////////////////////////////////////////////////////////
GR_DEFINE_EFFECT_TEST(GrPerlinNoiseEffect);
GrEffectRef* GrPerlinNoiseEffect::TestCreate(SkRandom* random,
GrContext* context,
const GrDrawTargetCaps&,
GrTexture**) {
int numOctaves = random->nextRangeU(2, 10);
bool stitchTiles = random->nextBool();
SkScalar seed = SkIntToScalar(random->nextU());
SkISize tileSize = SkISize::Make(random->nextRangeU(4, 4096), random->nextRangeU(4, 4096));
SkScalar baseFrequencyX = random->nextRangeScalar(0.01f,
0.99f);
SkScalar baseFrequencyY = random->nextRangeScalar(0.01f,
0.99f);
SkShader* shader = random->nextBool() ?
SkPerlinNoiseShader::CreateFractalNoise(baseFrequencyX, baseFrequencyY, numOctaves, seed,
stitchTiles ? &tileSize : NULL) :
SkPerlinNoiseShader::CreateTubulence(baseFrequencyX, baseFrequencyY, numOctaves, seed,
stitchTiles ? &tileSize : NULL);
SkPaint paint;
GrEffectRef* effect = shader->asNewEffect(context, paint);
SkDELETE(shader);
return effect;
}
/////////////////////////////////////////////////////////////////////
void GrGLSimplexNoise::emitCode(GrGLShaderBuilder* builder,
const GrDrawEffect&,
EffectKey key,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray& coords,
const TextureSamplerArray&) {
sk_ignore_unused_variable(inputColor);
SkString vCoords = builder->ensureFSCoords2D(coords, 0);
fSeedUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kFloat_GrSLType, "seed");
const char* seedUni = builder->getUniformCStr(fSeedUni);
fInvMatrixUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kMat33f_GrSLType, "invMatrix");
const char* invMatrixUni = builder->getUniformCStr(fInvMatrixUni);
fBaseFrequencyUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kVec2f_GrSLType, "baseFrequency");
const char* baseFrequencyUni = builder->getUniformCStr(fBaseFrequencyUni);
fAlphaUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kFloat_GrSLType, "alpha");
const char* alphaUni = builder->getUniformCStr(fAlphaUni);
// Add vec3 modulo 289 function
static const GrGLShaderVar gVec3Args[] = {
GrGLShaderVar("x", kVec3f_GrSLType)
};
SkString mod289_3_funcName;
builder->fsEmitFunction(kVec3f_GrSLType,
"mod289", SK_ARRAY_COUNT(gVec3Args), gVec3Args,
"const vec2 C = vec2(1.0 / 289.0, 289.0);\n"
"return x - floor(x * C.xxx) * C.yyy;", &mod289_3_funcName);
// Add vec4 modulo 289 function
static const GrGLShaderVar gVec4Args[] = {
GrGLShaderVar("x", kVec4f_GrSLType)
};
SkString mod289_4_funcName;
builder->fsEmitFunction(kVec4f_GrSLType,
"mod289", SK_ARRAY_COUNT(gVec4Args), gVec4Args,
"const vec2 C = vec2(1.0 / 289.0, 289.0);\n"
"return x - floor(x * C.xxxx) * C.yyyy;", &mod289_4_funcName);
// Add vec4 permute function
SkString permuteCode;
permuteCode.appendf("const vec2 C = vec2(34.0, 1.0);\n"
"return %s(((x * C.xxxx) + C.yyyy) * x);", mod289_4_funcName.c_str());
SkString permuteFuncName;
builder->fsEmitFunction(kVec4f_GrSLType,
"permute", SK_ARRAY_COUNT(gVec4Args), gVec4Args,
permuteCode.c_str(), &permuteFuncName);
// Add vec4 taylorInvSqrt function
SkString taylorInvSqrtFuncName;
builder->fsEmitFunction(kVec4f_GrSLType,
"taylorInvSqrt", SK_ARRAY_COUNT(gVec4Args), gVec4Args,
"const vec2 C = vec2(-0.85373472095314, 1.79284291400159);\n"
"return x * C.xxxx + C.yyyy;", &taylorInvSqrtFuncName);
// Add vec3 noise function
static const GrGLShaderVar gNoiseVec3Args[] = {
GrGLShaderVar("v", kVec3f_GrSLType)
};
SkString noiseCode;
noiseCode.append(
"const vec2 C = vec2(1.0/6.0, 1.0/3.0);\n"
"const vec4 D = vec4(0.0, 0.5, 1.0, 2.0);\n"
// First corner
"vec3 i = floor(v + dot(v, C.yyy));\n"
"vec3 x0 = v - i + dot(i, C.xxx);\n"
// Other corners
"vec3 g = step(x0.yzx, x0.xyz);\n"
"vec3 l = 1.0 - g;\n"
"vec3 i1 = min(g.xyz, l.zxy);\n"
"vec3 i2 = max(g.xyz, l.zxy);\n"
"vec3 x1 = x0 - i1 + C.xxx;\n"
"vec3 x2 = x0 - i2 + C.yyy;\n" // 2.0*C.x = 1/3 = C.y
"vec3 x3 = x0 - D.yyy;\n" // -1.0+3.0*C.x = -0.5 = -D.y
);
noiseCode.appendf(
// Permutations
"i = %s(i);\n"
"vec4 p = %s(%s(%s(\n"
" i.z + vec4(0.0, i1.z, i2.z, 1.0)) +\n"
" i.y + vec4(0.0, i1.y, i2.y, 1.0)) +\n"
" i.x + vec4(0.0, i1.x, i2.x, 1.0));\n",
mod289_3_funcName.c_str(), permuteFuncName.c_str(), permuteFuncName.c_str(),
permuteFuncName.c_str());
noiseCode.append(
// Gradients: 7x7 points over a square, mapped onto an octahedron.
// The ring size 17*17 = 289 is close to a multiple of 49 (49*6 = 294)
"float n_ = 0.142857142857;\n" // 1.0/7.0
"vec3 ns = n_ * D.wyz - D.xzx;\n"
"vec4 j = p - 49.0 * floor(p * ns.z * ns.z);\n" // mod(p,7*7)
"vec4 x_ = floor(j * ns.z);\n"
"vec4 y_ = floor(j - 7.0 * x_);" // mod(j,N)
"vec4 x = x_ *ns.x + ns.yyyy;\n"
"vec4 y = y_ *ns.x + ns.yyyy;\n"
"vec4 h = 1.0 - abs(x) - abs(y);\n"
"vec4 b0 = vec4(x.xy, y.xy);\n"
"vec4 b1 = vec4(x.zw, y.zw);\n"
);
noiseCode.append(
"vec4 s0 = floor(b0) * 2.0 + 1.0;\n"
"vec4 s1 = floor(b1) * 2.0 + 1.0;\n"
"vec4 sh = -step(h, vec4(0.0));\n"
"vec4 a0 = b0.xzyw + s0.xzyw * sh.xxyy;\n"
"vec4 a1 = b1.xzyw + s1.xzyw * sh.zzww;\n"
"vec3 p0 = vec3(a0.xy, h.x);\n"
"vec3 p1 = vec3(a0.zw, h.y);\n"
"vec3 p2 = vec3(a1.xy, h.z);\n"
"vec3 p3 = vec3(a1.zw, h.w);\n"
);
noiseCode.appendf(
// Normalise gradients
"vec4 norm = %s(vec4(dot(p0,p0), dot(p1,p1), dot(p2, p2), dot(p3,p3)));\n"
"p0 *= norm.x;\n"
"p1 *= norm.y;\n"
"p2 *= norm.z;\n"
"p3 *= norm.w;\n"
// Mix final noise value
"vec4 m = max(0.6 - vec4(dot(x0,x0), dot(x1,x1), dot(x2,x2), dot(x3,x3)), 0.0);\n"
"m = m * m;\n"
"return 42.0 * dot(m*m, vec4(dot(p0,x0), dot(p1,x1), dot(p2,x2), dot(p3,x3)));",
taylorInvSqrtFuncName.c_str());
SkString noiseFuncName;
builder->fsEmitFunction(kFloat_GrSLType,
"snoise", SK_ARRAY_COUNT(gNoiseVec3Args), gNoiseVec3Args,
noiseCode.c_str(), &noiseFuncName);
const char* noiseVecIni = "noiseVecIni";
const char* factors = "factors";
const char* sum = "sum";
const char* xOffsets = "xOffsets";
const char* yOffsets = "yOffsets";
const char* channel = "channel";
// Fill with some prime numbers
builder->fsCodeAppendf("\t\tconst vec4 %s = vec4(13.0, 53.0, 101.0, 151.0);\n", xOffsets);
builder->fsCodeAppendf("\t\tconst vec4 %s = vec4(109.0, 167.0, 23.0, 67.0);\n", yOffsets);
// There are rounding errors if the floor operation is not performed here
builder->fsCodeAppendf(
"\t\tvec3 %s = vec3(floor((%s*vec3(%s, 1.0)).xy) * vec2(0.66) * %s, 0.0);\n",
noiseVecIni, invMatrixUni, vCoords.c_str(), baseFrequencyUni);
// Perturb the texcoords with three components of noise
builder->fsCodeAppendf("\t\t%s += 0.1 * vec3(%s(%s + vec3( 0.0, 0.0, %s)),"
"%s(%s + vec3( 43.0, 17.0, %s)),"
"%s(%s + vec3(-17.0, -43.0, %s)));\n",
noiseVecIni, noiseFuncName.c_str(), noiseVecIni, seedUni,
noiseFuncName.c_str(), noiseVecIni, seedUni,
noiseFuncName.c_str(), noiseVecIni, seedUni);
builder->fsCodeAppendf("\t\t%s = vec4(0.0);\n", outputColor);
builder->fsCodeAppendf("\t\tvec3 %s = vec3(1.0);\n", factors);
builder->fsCodeAppendf("\t\tfloat %s = 0.0;\n", sum);
// Loop over all octaves
builder->fsCodeAppendf("\t\tfor (int octave = 0; octave < %d; ++octave) {\n", fNumOctaves);
// Loop over the 4 channels
builder->fsCodeAppendf("\t\t\tfor (int %s = 3; %s >= 0; --%s) {\n", channel, channel, channel);
builder->fsCodeAppendf(
"\t\t\t\t%s[channel] += %s.x * %s(%s * %s.yyy - vec3(%s[%s], %s[%s], %s * %s.z));\n",
outputColor, factors, noiseFuncName.c_str(), noiseVecIni, factors, xOffsets, channel,
yOffsets, channel, seedUni, factors);
builder->fsCodeAppend("\t\t\t}\n"); // end of the for loop on channels
builder->fsCodeAppendf("\t\t\t%s += %s.x;\n", sum, factors);
builder->fsCodeAppendf("\t\t\t%s *= vec3(0.5, 2.0, 0.75);\n", factors);
builder->fsCodeAppend("\t\t}\n"); // end of the for loop on octaves
if (fType == SkPerlinNoiseShader::kFractalNoise_Type) {
// The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
// by fractalNoise and (turbulenceFunctionResult) by turbulence.
builder->fsCodeAppendf("\t\t%s = %s * vec4(0.5 / %s) + vec4(0.5);\n",
outputColor, outputColor, sum);
} else {
builder->fsCodeAppendf("\t\t%s = abs(%s / vec4(%s));\n",
outputColor, outputColor, sum);
}
builder->fsCodeAppendf("\t\t%s.a *= %s;\n", outputColor, alphaUni);
// Clamp values
builder->fsCodeAppendf("\t\t%s = clamp(%s, 0.0, 1.0);\n", outputColor, outputColor);
// Pre-multiply the result
builder->fsCodeAppendf("\t\t%s = vec4(%s.rgb * %s.aaa, %s.a);\n",
outputColor, outputColor, outputColor, outputColor);
}
void GrGLPerlinNoise::emitCode(GrGLShaderBuilder* builder,
const GrDrawEffect&,
EffectKey key,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray& coords,
const TextureSamplerArray& samplers) {
sk_ignore_unused_variable(inputColor);
SkString vCoords = builder->ensureFSCoords2D(coords, 0);
fInvMatrixUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kMat33f_GrSLType, "invMatrix");
const char* invMatrixUni = builder->getUniformCStr(fInvMatrixUni);
fBaseFrequencyUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kVec2f_GrSLType, "baseFrequency");
const char* baseFrequencyUni = builder->getUniformCStr(fBaseFrequencyUni);
fAlphaUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kFloat_GrSLType, "alpha");
const char* alphaUni = builder->getUniformCStr(fAlphaUni);
const char* stitchDataUni = NULL;
if (fStitchTiles) {
fStitchDataUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kVec2f_GrSLType, "stitchData");
stitchDataUni = builder->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* noiseXY = "noiseXY";
const char* noiseVec = "noiseVec";
const char* noiseSmooth = "noiseSmooth";
const char* fractVal = "fractVal";
const char* uv = "uv";
const char* ab = "ab";
const char* latticeIdx = "latticeIdx";
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 * vec2(%s)) * vec2(2.0) - vec2(1.0)), %s);";
// Add noise function
static const GrGLShaderVar gPerlinNoiseArgs[] = {
GrGLShaderVar(chanCoord, kFloat_GrSLType),
GrGLShaderVar(noiseVec, kVec2f_GrSLType)
};
static const GrGLShaderVar gPerlinNoiseStitchArgs[] = {
GrGLShaderVar(chanCoord, kFloat_GrSLType),
GrGLShaderVar(noiseVec, kVec2f_GrSLType),
GrGLShaderVar(stitchData, kVec2f_GrSLType)
};
SkString noiseCode;
noiseCode.appendf("\tvec4 %s = vec4(floor(%s), fract(%s));", noiseXY, noiseVec, noiseVec);
// 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);
// 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);
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);
}
// Get texture coordinates and normalize
noiseCode.appendf("\n\t%s.xy = fract(floor(mod(%s.xy, 256.0)) / vec2(256.0));\n",
noiseXY, noiseXY);
// Get permutation for x
{
SkString xCoords("");
xCoords.appendf("vec2(%s.x, 0.5)", noiseXY);
noiseCode.appendf("\n\tvec2 %s;\n\t%s.x = ", latticeIdx, latticeIdx);
builder->appendTextureLookup(&noiseCode, samplers[0], xCoords.c_str(), kVec2f_GrSLType);
noiseCode.append(".r;");
}
// Get permutation for x + 1
{
SkString xCoords("");
xCoords.appendf("vec2(fract(%s.x + %s), 0.5)", noiseXY, inc8bit);
noiseCode.appendf("\n\t%s.y = ", latticeIdx);
builder->appendTextureLookup(&noiseCode, samplers[0], xCoords.c_str(), kVec2f_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 * vec2(255.0) + vec2(0.5)) * vec2(0.003921569);",
latticeIdx, latticeIdx);
#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\n\tvec2 %s;", uv);
// Compute u, at offset (0,0)
{
SkString latticeCoords("");
latticeCoords.appendf("vec2(%s.x, %s)", latticeIdx, chanCoord);
noiseCode.appendf("\n\tvec4 %s = ", lattice);
builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),
kVec2f_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("vec2(%s.y, %s)", latticeIdx, chanCoord);
noiseCode.append("\n\tlattice = ");
builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),
kVec2f_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\tvec2 %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("vec2(fract(%s.y + %s), %s)", latticeIdx, inc8bit, chanCoord);
noiseCode.append("\n\tlattice = ");
builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),
kVec2f_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("vec2(fract(%s.x + %s), %s)", latticeIdx, inc8bit, chanCoord);
noiseCode.append("\n\tlattice = ");
builder->appendTextureLookup(&noiseCode, samplers[1], latticeCoords.c_str(),
kVec2f_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 (fStitchTiles) {
builder->fsEmitFunction(kFloat_GrSLType,
"perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseStitchArgs),
gPerlinNoiseStitchArgs, noiseCode.c_str(), &noiseFuncName);
} else {
builder->fsEmitFunction(kFloat_GrSLType,
"perlinnoise", SK_ARRAY_COUNT(gPerlinNoiseArgs),
gPerlinNoiseArgs, noiseCode.c_str(), &noiseFuncName);
}
// There are rounding errors if the floor operation is not performed here
builder->fsCodeAppendf("\n\t\tvec2 %s = floor((%s * vec3(%s, 1.0)).xy) * %s;",
noiseVec, invMatrixUni, vCoords.c_str(), baseFrequencyUni);
// Clear the color accumulator
builder->fsCodeAppendf("\n\t\t%s = vec4(0.0);", outputColor);
if (fStitchTiles) {
// Set up TurbulenceInitial stitch values.
builder->fsCodeAppendf("\n\t\tvec2 %s = %s;", stitchData, stitchDataUni);
}
builder->fsCodeAppendf("\n\t\tfloat %s = 1.0;", ratio);
// Loop over all octaves
builder->fsCodeAppendf("\n\t\tfor (int octave = 0; octave < %d; ++octave) {", fNumOctaves);
builder->fsCodeAppendf("\n\t\t\t%s += ", outputColor);
if (fType != SkPerlinNoiseShader::kFractalNoise_Type) {
builder->fsCodeAppend("abs(");
}
if (fStitchTiles) {
builder->fsCodeAppendf(
"vec4(\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 {
builder->fsCodeAppendf(
"vec4(\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 (fType != SkPerlinNoiseShader::kFractalNoise_Type) {
builder->fsCodeAppendf(")"); // end of "abs("
}
builder->fsCodeAppendf(" * %s;", ratio);
builder->fsCodeAppendf("\n\t\t\t%s *= vec2(2.0);", noiseVec);
builder->fsCodeAppendf("\n\t\t\t%s *= 0.5;", ratio);
if (fStitchTiles) {
builder->fsCodeAppendf("\n\t\t\t%s *= vec2(2.0);", stitchData);
}
builder->fsCodeAppend("\n\t\t}"); // end of the for loop on octaves
if (fType == SkPerlinNoiseShader::kFractalNoise_Type) {
// The value of turbulenceFunctionResult comes from ((turbulenceFunctionResult) + 1) / 2
// by fractalNoise and (turbulenceFunctionResult) by turbulence.
builder->fsCodeAppendf("\n\t\t%s = %s * vec4(0.5) + vec4(0.5);", outputColor, outputColor);
}
builder->fsCodeAppendf("\n\t\t%s.a *= %s;", outputColor, alphaUni);
// Clamp values
builder->fsCodeAppendf("\n\t\t%s = clamp(%s, 0.0, 1.0);", outputColor, outputColor);
// Pre-multiply the result
builder->fsCodeAppendf("\n\t\t%s = vec4(%s.rgb * %s.aaa, %s.a);\n",
outputColor, outputColor, outputColor, outputColor);
}
GrGLNoise::GrGLNoise(const GrBackendEffectFactory& factory, const GrDrawEffect& drawEffect)
: INHERITED (factory)
, fType(drawEffect.castEffect<GrPerlinNoiseEffect>().type())
, fStitchTiles(drawEffect.castEffect<GrPerlinNoiseEffect>().stitchTiles())
, fNumOctaves(drawEffect.castEffect<GrPerlinNoiseEffect>().numOctaves()) {
}
GrGLEffect::EffectKey GrGLNoise::GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
const GrPerlinNoiseEffect& turbulence = drawEffect.castEffect<GrPerlinNoiseEffect>();
EffectKey key = turbulence.numOctaves();
key = key << 3; // Make room for next 3 bits
switch (turbulence.type()) {
case SkPerlinNoiseShader::kFractalNoise_Type:
key |= 0x1;
break;
case SkPerlinNoiseShader::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
}
return key;
}
void GrGLNoise::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
const GrPerlinNoiseEffect& turbulence = drawEffect.castEffect<GrPerlinNoiseEffect>();
const SkVector& baseFrequency = turbulence.baseFrequency();
uman.set2f(fBaseFrequencyUni, baseFrequency.fX, baseFrequency.fY);
uman.set1f(fAlphaUni, SkScalarDiv(SkIntToScalar(turbulence.alpha()), SkIntToScalar(255)));
SkMatrix m = turbulence.matrix();
m.postTranslate(-SK_Scalar1, -SK_Scalar1);
SkMatrix invM;
if (!m.invert(&invM)) {
invM.reset();
} else {
invM.postConcat(invM); // Square the matrix
}
uman.setSkMatrix(fInvMatrixUni, invM);
}
void GrGLPerlinNoise::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
INHERITED::setData(uman, drawEffect);
const GrPerlinNoiseEffect& turbulence = drawEffect.castEffect<GrPerlinNoiseEffect>();
if (turbulence.stitchTiles()) {
const SkPerlinNoiseShader::StitchData& stitchData = turbulence.stitchData();
uman.set2f(fStitchDataUni, SkIntToScalar(stitchData.fWidth),
SkIntToScalar(stitchData.fHeight));
}
}
void GrGLSimplexNoise::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
INHERITED::setData(uman, drawEffect);
const GrSimplexNoiseEffect& turbulence = drawEffect.castEffect<GrSimplexNoiseEffect>();
uman.set1f(fSeedUni, turbulence.seed());
}
/////////////////////////////////////////////////////////////////////
GrEffectRef* SkPerlinNoiseShader::asNewEffect(GrContext* context, const SkPaint& paint) const {
SkASSERT(NULL != context);
if (0 == fNumOctaves) {
SkColor clearColor = 0;
if (kFractalNoise_Type == fType) {
clearColor = SkColorSetARGB(paint.getAlpha() / 2, 127, 127, 127);
}
SkAutoTUnref<SkColorFilter> cf(SkColorFilter::CreateModeFilter(
clearColor, SkXfermode::kSrc_Mode));
return cf->asNewEffect(context);
}
// Either we don't stitch tiles, either we have a valid tile size
SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
#ifdef SK_USE_SIMPLEX_NOISE
// Simplex noise is currently disabled but can be enabled by defining SK_USE_SIMPLEX_NOISE
sk_ignore_unused_variable(context);
GrEffectRef* effect =
GrSimplexNoiseEffect::Create(fType, fPaintingData->fBaseFrequency,
fNumOctaves, fStitchTiles, fSeed,
this->getLocalMatrix(), paint.getAlpha());
#else
GrTexture* permutationsTexture = GrLockAndRefCachedBitmapTexture(
context, *fPaintingData->getPermutationsBitmap(), NULL);
GrTexture* noiseTexture = GrLockAndRefCachedBitmapTexture(
context, *fPaintingData->getNoiseBitmap(), NULL);
GrEffectRef* effect = (NULL != permutationsTexture) && (NULL != noiseTexture) ?
GrPerlinNoiseEffect::Create(fType, fPaintingData->fBaseFrequency,
fNumOctaves, fStitchTiles,
fPaintingData->fStitchDataInit,
permutationsTexture, noiseTexture,
this->getLocalMatrix(), paint.getAlpha()) :
NULL;
// Unlock immediately, this is not great, but we don't have a way of
// knowing when else to unlock it currently. TODO: Remove this when
// unref becomes the unlock replacement for all types of textures.
if (NULL != permutationsTexture) {
GrUnlockAndUnrefCachedBitmapTexture(permutationsTexture);
}
if (NULL != noiseTexture) {
GrUnlockAndUnrefCachedBitmapTexture(noiseTexture);
}
#endif
return effect;
}
#else
GrEffectRef* SkPerlinNoiseShader::asNewEffect(GrContext*, const SkPaint&) const {
SkDEBUGFAIL("Should not call in GPU-less build");
return NULL;
}
#endif
#ifdef SK_DEVELOPER
void SkPerlinNoiseShader::toString(SkString* str) const {
str->append("SkPerlinNoiseShader: (");
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