nr-filter-turbulence.cpp revision 9f6f7e74a1ded383518676e0ecb2ccc5caa73d25
/*
* feTurbulence filter primitive renderer
*
* Authors:
* World Wide Web Consortium <http://www.w3.org/>
* Felipe Corrêa da Silva Sanches <juca@members.fsf.org>
*
* This file has a considerable amount of code adapted from
* the W3C SVG filter specs, available at:
* http://www.w3.org/TR/SVG11/filters.html#feTurbulence
*
* W3C original code is licensed under the terms of
* the (GPL compatible) W3C® SOFTWARE NOTICE AND LICENSE:
* http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
*
* Copyright (C) 2007 authors
* Released under GNU GPL version 2 (or later), read the file 'COPYING' for more information
*/
#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 {
if (!_fractalnoise) {
guint32 r = CLAMP_D_TO_U8(turbulence(0, p)*255.0);
guint32 g = CLAMP_D_TO_U8(turbulence(1, p)*255.0);
guint32 b = CLAMP_D_TO_U8(turbulence(2, p)*255.0);
guint32 a = CLAMP_D_TO_U8(turbulence(3, p)*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;
} else {
guint32 r = CLAMP_D_TO_U8((turbulence(0, p)*255.0 + 255.0) / 2);
guint32 g = CLAMP_D_TO_U8((turbulence(1, p)*255.0 + 255.0) / 2);
guint32 b = CLAMP_D_TO_U8((turbulence(2, p)*255.0 + 255.0) / 2);
guint32 a = CLAMP_D_TO_U8((turbulence(3, p)*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;
}
}*/
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].
* Algorithm is: r = (a * r) mod m
* where a = 16807 and m = 2**31 - 1 = 2147483647
* See [Park & Miller], CACM vol. 31 no. 10 p. 1195, Oct. 1988
* To test: the algorithm should produce the result 1043618065
* as the 10,000th generated number if the original seed is 1. */
_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;
static double const PerlinOffset = 4096.0;
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 );
}
// std::cout << "FilterTurbulance: ci data: out: "
// << get_cairo_surface_ci(out) << std::endl;
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 */
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :