#include "display/cairo-templates.h"

#include "display/cairo-utils.h"

#include "display/nr-filter.h"

#include "display/nr-filter-turbulence.h"

#include "display/nr-filter-units.h"

#include "display/nr-filter-utils.h"

#include <math.h>

namespace Inkscape {

namespace Filters{

class TurbulenceGenerator {

public:

TurbulenceGenerator() :

_tile(),

_baseFreq(),

_latticeSelector(),

_gradient(),

_seed(0),

_octaves(0),

_stitchTiles(false),

_wrapx(0),

_wrapy(0),

_wrapw(0),

_wraph(0),

_inited(false),

_fractalnoise(false)

{}

void init(long seed, Geom::Rect const &tile, Geom::Point const &freq, bool stitch,

bool fractalnoise, int octaves)

{

// setup random number generator

_setupSeed(seed);

// set values

_tile = tile;

_baseFreq = freq;

_stitchTiles = stitch;

_fractalnoise = fractalnoise;

_octaves = octaves;

int i;

for (int k = 0; k < 4; ++k) {

for (i = 0; i < BSize; ++i) {

_latticeSelector[i] = i;

_gradient[i][k][0] = static_cast<double>(_random() % (BSize*2) - BSize) / BSize;

_gradient[i][k][1] = static_cast<double>(_random() % (BSize*2) - BSize) / BSize;

// normalize gradient

double s = hypot(_gradient[i][k][0], _gradient[i][k][1]);

_gradient[i][k][0] /= s;

_gradient[i][k][1] /= s;

}

}

while (--i) {

// shuffle lattice selectors

int j = _random() % BSize;

std::swap(_latticeSelector[i], _latticeSelector[j]);

}

// fill out the remaining part of the gradient

for (i = 0; i < BSize + 2; ++i)

{

_latticeSelector[BSize + i] = _latticeSelector[i];

for(int k = 0; k < 4; ++k) {

_gradient[BSize + i][k][0] = _gradient[i][k][0];

_gradient[BSize + i][k][1] = _gradient[i][k][1];

}

}

// When stitching tiled turbulence, the frequencies must be adjusted

// so that the tile borders will be continuous.

if (_stitchTiles) {

if (_baseFreq[Geom::X] != 0.0)

{

double freq = _baseFreq[Geom::X];

double lo = floor(_tile.width() * freq) / _tile.width();

double hi = ceil(_tile.width() * freq) / _tile.width();

_baseFreq[Geom::X] = freq / lo < hi / freq ? lo : hi;

}

if (_baseFreq[Geom::Y] != 0.0)

{

double freq = _baseFreq[Geom::Y];

double lo = floor(_tile.height() * freq) / _tile.height();

double hi = ceil(_tile.height() * freq) / _tile.height();

_baseFreq[Geom::Y] = freq / lo < hi / freq ? lo : hi;

}

_wrapw = _tile.width() * _baseFreq[Geom::X] + 0.5;

_wraph = _tile.height() * _baseFreq[Geom::Y] + 0.5;

_wrapx = _tile.left() * _baseFreq[Geom::X] + PerlinOffset + _wrapw;

_wrapy = _tile.top() * _baseFreq[Geom::Y] + PerlinOffset + _wraph;

}

_inited = true;

}

G_GNUC_PURE

guint32 turbulencePixel(Geom::Point const &p) const {

int wrapx = _wrapx, wrapy = _wrapy, wrapw = _wrapw, wraph = _wraph;

double pixel[4];

double x = p[Geom::X] * _baseFreq[Geom::X];

double y = p[Geom::Y] * _baseFreq[Geom::Y];

double ratio = 1.0;

for (int k = 0; k < 4; ++k)

pixel[k] = 0.0;

for(int octave = 0; octave < _octaves; ++octave)

{

double tx = x + PerlinOffset;

double bx = floor(tx);

double rx0 = tx - bx, rx1 = rx0 - 1.0;

int bx0 = bx, bx1 = bx0 + 1;

double ty = y + PerlinOffset;

double by = floor(ty);

double ry0 = ty - by, ry1 = ry0 - 1.0;

int by0 = by, by1 = by0 + 1;

if (_stitchTiles) {

if (bx0 >= wrapx) bx0 -= wrapw;

if (bx1 >= wrapx) bx1 -= wrapw;

if (by0 >= wrapy) by0 -= wraph;

if (by1 >= wrapy) by1 -= wraph;

}

bx0 &= BMask;

bx1 &= BMask;

by0 &= BMask;

by1 &= BMask;

int i = _latticeSelector[bx0];

int j = _latticeSelector[bx1];

int b00 = _latticeSelector[i + by0];

int b01 = _latticeSelector[i + by1];

int b10 = _latticeSelector[j + by0];

int b11 = _latticeSelector[j + by1];

double sx = _scurve(rx0);

double sy = _scurve(ry0);

double result[4];

// channel numbering: R=0, G=1, B=2, A=3

for (int k = 0; k < 4; ++k) {

double const *qxa = _gradient[b00][k];

double const *qxb = _gradient[b10][k];

double a = _lerp(sx, rx0 * qxa[0] + ry0 * qxa[1],

rx1 * qxb[0] + ry0 * qxb[1]);

double const *qya = _gradient[b01][k];

double const *qyb = _gradient[b11][k];

double b = _lerp(sx, rx0 * qya[0] + ry1 * qya[1],

rx1 * qyb[0] + ry1 * qyb[1]);

result[k] = _lerp(sy, a, b);

}

if (_fractalnoise) {

for (int k = 0; k < 4; ++k)

pixel[k] += result[k] / ratio;

} else {

for (int k = 0; k < 4; ++k)

pixel[k] += fabs(result[k]) / ratio;

}

x *= 2;

y *= 2;

ratio *= 2;

if(_stitchTiles)

{

// Update stitch values. Subtracting PerlinOffset before the multiplication and

// adding it afterward simplifies to subtracting it once.

wrapw *= 2;

wraph *= 2;

wrapx = wrapx*2 - PerlinOffset;

wrapy = wrapy*2 - PerlinOffset;

}

}

if (_fractalnoise) {

guint32 r = CLAMP_D_TO_U8((pixel[0]*255.0 + 255.0) / 2);

guint32 g = CLAMP_D_TO_U8((pixel[1]*255.0 + 255.0) / 2);

guint32 b = CLAMP_D_TO_U8((pixel[2]*255.0 + 255.0) / 2);

guint32 a = CLAMP_D_TO_U8((pixel[3]*255.0 + 255.0) / 2);

r = premul_alpha(r, a);

g = premul_alpha(g, a);

b = premul_alpha(b, a);

ASSEMBLE_ARGB32(pxout, a,r,g,b);

return pxout;

} else {

guint32 r = CLAMP_D_TO_U8(pixel[0]*255.0);

guint32 g = CLAMP_D_TO_U8(pixel[1]*255.0);

guint32 b = CLAMP_D_TO_U8(pixel[2]*255.0);

guint32 a = CLAMP_D_TO_U8(pixel[3]*255.0);

r = premul_alpha(r, a);

g = premul_alpha(g, a);

b = premul_alpha(b, a);

ASSEMBLE_ARGB32(pxout, a,r,g,b);

return pxout;

}

}

//G_GNUC_PURE

/*guint32 turbulencePixel(Geom::Point const &p) const {

bool ready() const { return _inited; }

void dirty() { _inited = false; }

private:

void _setupSeed(long seed) {

_seed = seed;

if (_seed <= 0) _seed = -(_seed % (RAND_m - 1)) + 1;

if (_seed > RAND_m - 1) _seed = RAND_m - 1;

}

long _random() {

/* Produces results in the range [1, 2**31 - 2].

_seed = RAND_a * (_seed % RAND_q) - RAND_r * (_seed / RAND_q);

if (_seed <= 0) _seed += RAND_m;

return _seed;

}

static inline double _scurve(double t) {

return t * t * (3.0 - 2.0*t);

}

static inline double _lerp(double t, double a, double b) {

return a + t * (b-a);

}

// random number generator constants

static long const

RAND_m = 2147483647, // 2**31 - 1

RAND_a = 16807, // 7**5; primitive root of m

RAND_q = 127773, // m / a

RAND_r = 2836; // m % a

// other constants

static int const BSize = 0x100;

static int const BMask = 0xff;

#if __cplusplus < 201103L

static double const PerlinOffset = 4096.0;

#else

static double constexpr PerlinOffset = 4096.0;

#endif

Geom::Rect _tile;

Geom::Point _baseFreq;

int _latticeSelector[2*BSize + 2];

double _gradient[2*BSize + 2][4][2];

long _seed;

int _octaves;

bool _stitchTiles;

int _wrapx;

int _wrapy;

int _wrapw;

int _wraph;

bool _inited;

bool _fractalnoise;

};

FilterTurbulence::FilterTurbulence()

: gen(new TurbulenceGenerator())

, XbaseFrequency(0)

, YbaseFrequency(0)

, numOctaves(1)

, seed(0)

, updated(false)

, fTileWidth(10) //guessed

, fTileHeight(10) //guessed

, fTileX(1) //guessed

, fTileY(1) //guessed

{

}

FilterPrimitive * FilterTurbulence::create() {

return new FilterTurbulence();

}

FilterTurbulence::~FilterTurbulence()

{

delete gen;

}

void FilterTurbulence::set_baseFrequency(int axis, double freq){

if (axis==0) XbaseFrequency=freq;

if (axis==1) YbaseFrequency=freq;

gen->dirty();

}

void FilterTurbulence::set_numOctaves(int num){

numOctaves = num;

gen->dirty();

}

void FilterTurbulence::set_seed(double s){

seed = s;

gen->dirty();

}

void FilterTurbulence::set_stitchTiles(bool st){

stitchTiles = st;

gen->dirty();

}

void FilterTurbulence::set_type(FilterTurbulenceType t){

type = t;

gen->dirty();

}

void FilterTurbulence::set_updated(bool /*u*/)

{

}

struct Turbulence {

Turbulence(TurbulenceGenerator const &gen, Geom::Affine const &trans, int x0, int y0)

: _gen(gen)

, _trans(trans)

, _x0(x0), _y0(y0)

{}

guint32 operator()(int x, int y) {

Geom::Point point(x + _x0, y + _y0);

point *= _trans;

return _gen.turbulencePixel(point);

}

private:

TurbulenceGenerator const &_gen;

Geom::Affine _trans;

int _x0, _y0;

};

void FilterTurbulence::render_cairo(FilterSlot &slot)

{

cairo_surface_t *input = slot.getcairo(_input);

cairo_surface_t *out = ink_cairo_surface_create_same_size(input, CAIRO_CONTENT_COLOR_ALPHA);

// color_interpolation_filter is determined by CSS value (see spec. Turbulence).

if( _style ) {

set_cairo_surface_ci(out, (SPColorInterpolation)_style->color_interpolation_filters.computed );

}

if (!gen->ready()) {

Geom::Point ta(fTileX, fTileY);

Geom::Point tb(fTileX + fTileWidth, fTileY + fTileHeight);

gen->init(seed, Geom::Rect(ta, tb),

Geom::Point(XbaseFrequency, YbaseFrequency), stitchTiles,

type == TURBULENCE_FRACTALNOISE, numOctaves);

}

Geom::Affine unit_trans = slot.get_units().get_matrix_primitiveunits2pb().inverse();

Geom::Rect slot_area = slot.get_slot_area();

double x0 = slot_area.min()[Geom::X];

double y0 = slot_area.min()[Geom::Y];

ink_cairo_surface_synthesize(out, Turbulence(*gen, unit_trans, x0, y0));

cairo_surface_mark_dirty(out);

slot.set(_output, out);

cairo_surface_destroy(out);

}

double FilterTurbulence::complexity(Geom::Affine const &)

{

return 5.0;

}

} /* namespace Filters */

} /* namespace Inkscape */