/usr/include/mapnik/agg/agg_span_gradient.h is in libmapnik-dev 2.2.0+ds1-6build2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 | //----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.4
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://www.antigrain.com
//----------------------------------------------------------------------------
#ifndef AGG_SPAN_GRADIENT_INCLUDED
#define AGG_SPAN_GRADIENT_INCLUDED
#include <cmath>
#include <cstdlib>
#include <cstring>
#include "agg_basics.h"
#include "agg_math.h"
#include "agg_array.h"
namespace agg
{
enum gradient_subpixel_scale_e
{
gradient_subpixel_shift = 4, //-----gradient_subpixel_shift
gradient_subpixel_scale = 1 << gradient_subpixel_shift, //-----gradient_subpixel_scale
gradient_subpixel_mask = gradient_subpixel_scale - 1 //-----gradient_subpixel_mask
};
//==========================================================span_gradient
template<class ColorT,
class Interpolator,
class GradientF,
class ColorF>
class span_gradient
{
public:
typedef Interpolator interpolator_type;
typedef ColorT color_type;
enum downscale_shift_e
{
downscale_shift = interpolator_type::subpixel_shift -
gradient_subpixel_shift
};
//--------------------------------------------------------------------
span_gradient() {}
//--------------------------------------------------------------------
span_gradient(interpolator_type& inter,
const GradientF& gradient_function,
const ColorF& color_function,
double d1, double d2) :
m_interpolator(&inter),
m_gradient_function(&gradient_function),
m_color_function(&color_function),
m_d1(iround(d1 * gradient_subpixel_scale)),
m_d2(iround(d2 * gradient_subpixel_scale))
{}
//--------------------------------------------------------------------
interpolator_type& interpolator() { return *m_interpolator; }
const GradientF& gradient_function() const { return *m_gradient_function; }
const ColorF& color_function() const { return *m_color_function; }
double d1() const { return double(m_d1) / gradient_subpixel_scale; }
double d2() const { return double(m_d2) / gradient_subpixel_scale; }
//--------------------------------------------------------------------
void interpolator(interpolator_type& i) { m_interpolator = &i; }
void gradient_function(const GradientF& gf) { m_gradient_function = &gf; }
void color_function(const ColorF& cf) { m_color_function = &cf; }
void d1(double v) { m_d1 = iround(v * gradient_subpixel_scale); }
void d2(double v) { m_d2 = iround(v * gradient_subpixel_scale); }
//--------------------------------------------------------------------
void prepare() {}
//--------------------------------------------------------------------
void generate(color_type* span, int x, int y, unsigned len)
{
int dd = m_d2 - m_d1;
if(dd < 1) dd = 1;
m_interpolator->begin(x+0.5, y+0.5, len);
do
{
m_interpolator->coordinates(&x, &y);
int d = m_gradient_function->calculate(x >> downscale_shift,
y >> downscale_shift, m_d2);
d = ((d - m_d1) * (int)m_color_function->size()) / dd;
if(d < 0) d = 0;
if(d >= (int)m_color_function->size()) d = m_color_function->size() - 1;
*span++ = (*m_color_function)[d];
++(*m_interpolator);
}
while(--len);
}
private:
interpolator_type* m_interpolator;
const GradientF* m_gradient_function;
const ColorF* m_color_function;
int m_d1;
int m_d2;
};
//=====================================================gradient_linear_color
template<class ColorT>
struct gradient_linear_color
{
typedef ColorT color_type;
gradient_linear_color() {}
gradient_linear_color(const color_type& c1, const color_type& c2,
unsigned size = 256) :
m_c1(c1), m_c2(c2), m_size(size) {}
unsigned size() const { return m_size; }
color_type operator [] (unsigned v) const
{
return m_c1.gradient(m_c2, double(v) / double(m_size - 1));
}
void colors(const color_type& c1, const color_type& c2, unsigned size = 256)
{
m_c1 = c1;
m_c2 = c2;
m_size = size;
}
color_type m_c1;
color_type m_c2;
unsigned m_size;
};
//==========================================================gradient_circle
class gradient_circle
{
// Actually the same as radial. Just for compatibility
public:
static AGG_INLINE int calculate(int x, int y, int)
{
return int(fast_sqrt(x*x + y*y));
}
};
//==========================================================gradient_radial
class gradient_radial
{
public:
static AGG_INLINE int calculate(int x, int y, int)
{
return int(fast_sqrt(x*x + y*y));
}
};
//========================================================gradient_radial_d
class gradient_radial_d
{
public:
static AGG_INLINE int calculate(int x, int y, int)
{
return uround(sqrt(double(x)*double(x) + double(y)*double(y)));
}
};
//====================================================gradient_radial_focus
class gradient_radial_focus
{
public:
//---------------------------------------------------------------------
gradient_radial_focus() :
m_r(100 * gradient_subpixel_scale),
m_fx(0),
m_fy(0)
{
update_values();
}
//---------------------------------------------------------------------
gradient_radial_focus(double r, double fx, double fy) :
m_r (iround(r * gradient_subpixel_scale)),
m_fx(iround(fx * gradient_subpixel_scale)),
m_fy(iround(fy * gradient_subpixel_scale))
{
update_values();
}
//---------------------------------------------------------------------
void init(double r, double fx, double fy)
{
m_r = iround(r * gradient_subpixel_scale);
m_fx = iround(fx * gradient_subpixel_scale);
m_fy = iround(fy * gradient_subpixel_scale);
update_values();
}
//---------------------------------------------------------------------
double radius() const { return double(m_r) / gradient_subpixel_scale; }
double focus_x() const { return double(m_fx) / gradient_subpixel_scale; }
double focus_y() const { return double(m_fy) / gradient_subpixel_scale; }
//---------------------------------------------------------------------
int calculate(int x, int y, int) const
{
double dx = x - m_fx;
double dy = y - m_fy;
double d2 = dx * m_fy - dy * m_fx;
double d3 = m_r2 * (dx * dx + dy * dy) - d2 * d2;
return iround((dx * m_fx + dy * m_fy + sqrt(fabs(d3))) * m_mul);
}
private:
//---------------------------------------------------------------------
void update_values()
{
// Calculate the invariant values. In case the focal center
// lies exactly on the gradient circle the divisor degenerates
// into zero. In this case we just move the focal center by
// one subpixel unit possibly in the direction to the origin (0,0)
// and calculate the values again.
//-------------------------
m_r2 = double(m_r) * double(m_r);
m_fx2 = double(m_fx) * double(m_fx);
m_fy2 = double(m_fy) * double(m_fy);
double d = (m_r2 - (m_fx2 + m_fy2));
if(d == 0)
{
if(m_fx) { if(m_fx < 0) ++m_fx; else --m_fx; }
if(m_fy) { if(m_fy < 0) ++m_fy; else --m_fy; }
m_fx2 = double(m_fx) * double(m_fx);
m_fy2 = double(m_fy) * double(m_fy);
d = (m_r2 - (m_fx2 + m_fy2));
}
m_mul = m_r / d;
}
int m_r;
int m_fx;
int m_fy;
double m_r2;
double m_fx2;
double m_fy2;
double m_mul;
};
//==============================================================gradient_x
class gradient_x
{
public:
static int calculate(int x, int, int) { return x; }
};
//==============================================================gradient_y
class gradient_y
{
public:
static int calculate(int, int y, int) { return y; }
};
//========================================================gradient_diamond
class gradient_diamond
{
public:
static AGG_INLINE int calculate(int x, int y, int)
{
int ax = abs(x);
int ay = abs(y);
return ax > ay ? ax : ay;
}
};
//=============================================================gradient_xy
class gradient_xy
{
public:
static AGG_INLINE int calculate(int x, int y, int d)
{
return abs(x) * abs(y) / d;
}
};
//========================================================gradient_sqrt_xy
class gradient_sqrt_xy
{
public:
static AGG_INLINE int calculate(int x, int y, int)
{
return fast_sqrt(abs(x) * abs(y));
}
};
//==========================================================gradient_conic
class gradient_conic
{
public:
static AGG_INLINE int calculate(int x, int y, int d)
{
return uround(fabs(atan2(double(y), double(x))) * double(d) / pi);
}
};
//=================================================gradient_repeat_adaptor
template<class GradientF> class gradient_repeat_adaptor
{
public:
gradient_repeat_adaptor(const GradientF& gradient) :
m_gradient(&gradient) {}
AGG_INLINE int calculate(int x, int y, int d) const
{
int ret = m_gradient->calculate(x, y, d) % d;
if(ret < 0) ret += d;
return ret;
}
private:
const GradientF* m_gradient;
};
//================================================gradient_reflect_adaptor
template<class GradientF> class gradient_reflect_adaptor
{
public:
gradient_reflect_adaptor(const GradientF& gradient) :
m_gradient(&gradient) {}
AGG_INLINE int calculate(int x, int y, int d) const
{
int d2 = d << 1;
int ret = m_gradient->calculate(x, y, d) % d2;
if(ret < 0) ret += d2;
if(ret >= d) ret = d2 - ret;
return ret;
}
private:
const GradientF* m_gradient;
};
}
#endif
|