Dogcows Code - chaz/openbox/blob - render/gradient.c

   1 /* -*- indent-tabs-mode: nil; tab-width: 4; c-basic-offset: 4; -*-
   2
   3    gradient.c for the Openbox window manager
   4    Copyright (c) 2006        Mikael Magnusson
   5    Copyright (c) 2003        Ben Jansens
   6    Copyright (c) 2003        Derek Foreman
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    See the COPYING file for a copy of the GNU General Public License.
  19 */
  20
  21 #include "render.h"
  22 #include "gradient.h"
  23 #include "color.h"
  24 #include <glib.h>
  25
  26 static void highlight(RrPixel32 *x, RrPixel32 *y, gboolean raised);
  27 static void gradient_solid(RrAppearance *l, gint w, gint h);
  28 static void gradient_splitvertical(RrAppearance *a, gint w, gint h);
  29 static void gradient_vertical(RrSurface *sf, gint w, gint h);
  30 static void gradient_horizontal(RrSurface *sf, gint w, gint h);
  31 static void gradient_mirrorhorizontal(RrSurface *sf, gint w, gint h);
  32 static void gradient_diagonal(RrSurface *sf, gint w, gint h);
  33 static void gradient_crossdiagonal(RrSurface *sf, gint w, gint h);
  34 static void gradient_pyramid(RrSurface *sf, gint inw, gint inh);
  35
  36 void RrRender(RrAppearance *a, gint w, gint h)
  37 {
  38     RrPixel32 *data = a->surface.pixel_data;
  39     RrPixel32 current;
  40     guint r,g,b;
  41     gint off, x;
  42
  43     switch (a->surface.grad) {
  44     case RR_SURFACE_SOLID:
  45         gradient_solid(a, w, h);
  46         break;
  47     case RR_SURFACE_SPLIT_VERTICAL:
  48         gradient_splitvertical(a, w, h);
  49         break;
  50     case RR_SURFACE_VERTICAL:
  51         gradient_vertical(&a->surface, w, h);
  52         break;
  53     case RR_SURFACE_HORIZONTAL:
  54         gradient_horizontal(&a->surface, w, h);
  55         break;
  56     case RR_SURFACE_MIRROR_HORIZONTAL:
  57         gradient_mirrorhorizontal(&a->surface, w, h);
  58         break;
  59     case RR_SURFACE_DIAGONAL:
  60         gradient_diagonal(&a->surface, w, h);
  61         break;
  62     case RR_SURFACE_CROSS_DIAGONAL:
  63         gradient_crossdiagonal(&a->surface, w, h);
  64         break;
  65     case RR_SURFACE_PYRAMID:
  66         gradient_pyramid(&a->surface, w, h);
  67         break;
  68     default:
  69         g_assert_not_reached(); /* unhandled gradient */
  70         return;
  71     }
  72
  73     if (a->surface.interlaced) {
  74         gint i;
  75         RrPixel32 *p;
  76
  77         r = a->surface.interlace_color->r;
  78         g = a->surface.interlace_color->g;
  79         b = a->surface.interlace_color->b;
  80         current = (r << RrDefaultRedOffset)
  81             + (g << RrDefaultGreenOffset)
  82             + (b << RrDefaultBlueOffset);
  83         p = data;
  84         for (i = 0; i < h; i += 2, p += w)
  85             for (x = 0; x < w; ++x, ++p)
  86                 *p = current;
  87     }
  88
  89     if (a->surface.relief == RR_RELIEF_FLAT && a->surface.border) {
  90         r = a->surface.border_color->r;
  91         g = a->surface.border_color->g;
  92         b = a->surface.border_color->b;
  93         current = (r << RrDefaultRedOffset)
  94             + (g << RrDefaultGreenOffset)
  95             + (b << RrDefaultBlueOffset);
  96         for (off = 0, x = 0; x < w; ++x, off++) {
  97             *(data + off) = current;
  98             *(data + off + ((h-1) * w)) = current;
  99         }
 100         for (off = 0, x = 0; x < h; ++x, off++) {
 101             *(data + (off * w)) = current;
 102             *(data + (off * w) + w - 1) = current;
 103         }
 104     }
 105
 106     if (a->surface.relief != RR_RELIEF_FLAT) {
 107         if (a->surface.bevel == RR_BEVEL_1) {
 108             for (off = 1, x = 1; x < w - 1; ++x, off++)
 109                 highlight(data + off,
 110                           data + off + (h-1) * w,
 111                           a->surface.relief==RR_RELIEF_RAISED);
 112             for (off = 0, x = 0; x < h; ++x, off++)
 113                 highlight(data + off * w,
 114                           data + off * w + w - 1,
 115                           a->surface.relief==RR_RELIEF_RAISED);
 116         }
 117
 118         if (a->surface.bevel == RR_BEVEL_2) {
 119             for (off = 2, x = 2; x < w - 2; ++x, off++)
 120                 highlight(data + off + w,
 121                           data + off + (h-2) * w,
 122                           a->surface.relief==RR_RELIEF_RAISED);
 123             for (off = 1, x = 1; x < h-1; ++x, off++)
 124                 highlight(data + off * w + 1,
 125                           data + off * w + w - 2,
 126                           a->surface.relief==RR_RELIEF_RAISED);
 127         }
 128     }
 129 }
 130
 131 static void highlight(RrPixel32 *x, RrPixel32 *y, gboolean raised)
 132 {
 133     gint r, g, b;
 134
 135     RrPixel32 *up, *down;
 136     if (raised) {
 137         up = x;
 138         down = y;
 139     } else {
 140         up = y;
 141         down = x;
 142     }
 143     r = (*up >> RrDefaultRedOffset) & 0xFF;
 144     r += r >> 1;
 145     g = (*up >> RrDefaultGreenOffset) & 0xFF;
 146     g += g >> 1;
 147     b = (*up >> RrDefaultBlueOffset) & 0xFF;
 148     b += b >> 1;
 149     if (r > 0xFF) r = 0xFF;
 150     if (g > 0xFF) g = 0xFF;
 151     if (b > 0xFF) b = 0xFF;
 152     *up = (r << RrDefaultRedOffset) + (g << RrDefaultGreenOffset)
 153         + (b << RrDefaultBlueOffset);
 154
 155     r = (*down >> RrDefaultRedOffset) & 0xFF;
 156     r = (r >> 1) + (r >> 2);
 157     g = (*down >> RrDefaultGreenOffset) & 0xFF;
 158     g = (g >> 1) + (g >> 2);
 159     b = (*down >> RrDefaultBlueOffset) & 0xFF;
 160     b = (b >> 1) + (b >> 2);
 161     *down = (r << RrDefaultRedOffset) + (g << RrDefaultGreenOffset)
 162         + (b << RrDefaultBlueOffset);
 163 }
 164
 165 static void create_bevel_colors(RrAppearance *l)
 166 {
 167     gint r, g, b;
 168
 169     /* light color */
 170     r = l->surface.primary->r;
 171     r += r >> 1;
 172     g = l->surface.primary->g;
 173     g += g >> 1;
 174     b = l->surface.primary->b;
 175     b += b >> 1;
 176     if (r > 0xFF) r = 0xFF;
 177     if (g > 0xFF) g = 0xFF;
 178     if (b > 0xFF) b = 0xFF;
 179     g_assert(!l->surface.bevel_light);
 180     l->surface.bevel_light = RrColorNew(l->inst, r, g, b);
 181
 182     /* dark color */
 183     r = l->surface.primary->r;
 184     r = (r >> 1) + (r >> 2);
 185     g = l->surface.primary->g;
 186     g = (g >> 1) + (g >> 2);
 187     b = l->surface.primary->b;
 188     b = (b >> 1) + (b >> 2);
 189     g_assert(!l->surface.bevel_dark);
 190     l->surface.bevel_dark = RrColorNew(l->inst, r, g, b);
 191 }
 192
 193 static void gradient_solid(RrAppearance *l, gint w, gint h)
 194 {
 195     gint i;
 196     RrPixel32 pix;
 197     RrPixel32 *data = l->surface.pixel_data;
 198     RrSurface *sp = &l->surface;
 199     gint left = 0, top = 0, right = w - 1, bottom = h - 1;
 200
 201     pix = (sp->primary->r << RrDefaultRedOffset)
 202         + (sp->primary->g << RrDefaultGreenOffset)
 203         + (sp->primary->b << RrDefaultBlueOffset);
 204
 205     for (i = 0; i < w * h; i++)
 206         *data++ = pix;
 207
 208     if (sp->interlaced)
 209         return;
 210
 211     XFillRectangle(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->primary),
 212                    0, 0, w, h);
 213
 214     switch (sp->relief) {
 215     case RR_RELIEF_RAISED:
 216         if (!sp->bevel_dark)
 217             create_bevel_colors(l);
 218
 219         switch (sp->bevel) {
 220         case RR_BEVEL_1:
 221             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 222                       left, bottom, right, bottom);
 223             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 224                       right, bottom, right, top);
 225
 226             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 227                       left, top, right, top);
 228             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 229                       left, bottom, left, top);
 230             break;
 231         case RR_BEVEL_2:
 232             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 233                       left + 2, bottom - 1, right - 2, bottom - 1);
 234             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 235                       right - 1, bottom - 1, right - 1, top + 1);
 236
 237             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 238                       left + 2, top + 1, right - 2, top + 1);
 239             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 240                       left + 1, bottom - 1, left + 1, top + 1);
 241             break;
 242         default:
 243             g_assert_not_reached(); /* unhandled BevelType */
 244         }
 245         break;
 246     case RR_RELIEF_SUNKEN:
 247         if (!sp->bevel_dark)
 248             create_bevel_colors(l);
 249
 250         switch (sp->bevel) {
 251         case RR_BEVEL_1:
 252             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 253                       left, bottom, right, bottom);
 254             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 255                       right, bottom, right, top);
 256
 257             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 258                       left, top, right, top);
 259             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 260                       left, bottom, left, top);
 261             break;
 262         case RR_BEVEL_2:
 263             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 264                       left + 2, bottom - 1, right - 2, bottom - 1);
 265             XDrawLine(RrDisplay(l->inst), l->pixmap,RrColorGC(sp->bevel_light),
 266                       right - 1, bottom - 1, right - 1, top + 1);
 267
 268             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 269                       left + 2, top + 1, right - 2, top + 1);
 270             XDrawLine(RrDisplay(l->inst), l->pixmap, RrColorGC(sp->bevel_dark),
 271                       left + 1, bottom - 1, left + 1, top + 1);
 272             break;
 273         default:
 274             g_assert_not_reached(); /* unhandled BevelType */
 275         }
 276         break;
 277     case RR_RELIEF_FLAT:
 278         if (sp->border) {
 279             XDrawRectangle(RrDisplay(l->inst), l->pixmap,
 280                            RrColorGC(sp->border_color),
 281                            left, top, right, bottom);
 282         }
 283         break;
 284     default:
 285         g_assert_not_reached(); /* unhandled ReliefType */
 286     }
 287 }
 288
 289 /* * * * * * * * * * * * * * GRADIENT MAGIC WOOT * * * * * * * * * * * * * * */
 290
 291 #define VARS(x)                                                     \
 292     guint color##x[3];                                       \
 293     gint len##x, cdelta##x[3], error##x[3] = { 0, 0, 0 }, inc##x[3]; \
 294     gboolean bigslope##x[3] /* color slope > 1 */
 295
 296 #define SETUP(x, from, to, w)         \
 297     len##x = w;                       \
 298                                       \
 299     color##x[0] = from->r;            \
 300     color##x[1] = from->g;            \
 301     color##x[2] = from->b;            \
 302                                       \
 303     cdelta##x[0] = to->r - from->r;   \
 304     cdelta##x[1] = to->g - from->g;   \
 305     cdelta##x[2] = to->b - from->b;   \
 306                                       \
 307     if (cdelta##x[0] < 0) {           \
 308         cdelta##x[0] = -cdelta##x[0]; \
 309         inc##x[0] = -1;               \
 310     } else                            \
 311         inc##x[0] = 1;                \
 312     if (cdelta##x[1] < 0) {           \
 313         cdelta##x[1] = -cdelta##x[1]; \
 314         inc##x[1] = -1;               \
 315     } else                            \
 316         inc##x[1] = 1;                \
 317     if (cdelta##x[2] < 0) {           \
 318         cdelta##x[2] = -cdelta##x[2]; \
 319         inc##x[2] = -1;               \
 320     } else                            \
 321         inc##x[2] = 1;                \
 322     bigslope##x[0] = cdelta##x[0] > w;\
 323     bigslope##x[1] = cdelta##x[1] > w;\
 324     bigslope##x[2] = cdelta##x[2] > w
 325
 326 #define COLOR_RR(x, c)                       \
 327     c->r = color##x[0];                      \
 328     c->g = color##x[1];                      \
 329     c->b = color##x[2]
 330
 331 #define COLOR(x)                             \
 332     ((color##x[0] << RrDefaultRedOffset) +   \
 333      (color##x[1] << RrDefaultGreenOffset) + \
 334      (color##x[2] << RrDefaultBlueOffset))
 335
 336 #define INCREMENT(x, i) \
 337     (inc##x[i])
 338
 339 #define NEXT(x)                                           \
 340 {                                                         \
 341     gint i;                                                \
 342     for (i = 2; i >= 0; --i) {                            \
 343         if (!cdelta##x[i]) continue;                      \
 344                                                           \
 345         if (!bigslope##x[i]) {                            \
 346             /* Y (color) is dependant on X */             \
 347             error##x[i] += cdelta##x[i];                  \
 348             if ((error##x[i] << 1) >= len##x) {           \
 349                 color##x[i] += INCREMENT(x, i);           \
 350                 error##x[i] -= len##x;                    \
 351             }                                             \
 352         } else {                                          \
 353             /* X is dependant on Y (color) */             \
 354             while (1) {                                   \
 355                 color##x[i] += INCREMENT(x, i);           \
 356                 error##x[i] += len##x;                    \
 357                 if ((error##x[i] << 1) >= cdelta##x[i]) { \
 358                     error##x[i] -= cdelta##x[i];          \
 359                     break;                                \
 360                 }                                         \
 361             }                                             \
 362         }                                                 \
 363     }                                                     \
 364 }
 365
 366 static void gradient_splitvertical(RrAppearance *a, gint w, gint h)
 367 {
 368     gint x, y1, y3, r, g, b;
 369     RrSurface *sf = &a->surface;
 370     RrPixel32 *data = sf->pixel_data;
 371     RrPixel32 current;
 372     RrColor *primary_light, *secondary_light;
 373
 374     r = sf->primary->r;
 375     r += r >> 2;
 376     g = sf->primary->g;
 377     g += g >> 2;
 378     b = sf->primary->b;
 379     b += b >> 2;
 380     if (r > 0xFF) r = 0xFF;
 381     if (g > 0xFF) g = 0xFF;
 382     if (b > 0xFF) b = 0xFF;
 383       primary_light = RrColorNew(a->inst, r, g, b);
 384
 385     r = sf->secondary->r;
 386     r += r >> 4;
 387     g = sf->secondary->g;
 388     g += g >> 4;
 389     b = sf->secondary->b;
 390     b += b >> 4;
 391     if (r > 0xFF) r = 0xFF;
 392     if (g > 0xFF) g = 0xFF;
 393     if (b > 0xFF) b = 0xFF;
 394     secondary_light = RrColorNew(a->inst, r, g, b);
 395
 396     VARS(y1);
 397     SETUP(y1, primary_light, sf->primary, (h / 2) -1);
 398
 399     VARS(y3);
 400     SETUP(y3, sf->secondary, secondary_light,  (h / 2) -1);
 401
 402     for (y1 = h - 1; y1 > (h / 2) -1; --y1) {  /* 0 -> h-1 */
 403         current = COLOR(y1);
 404         for (x = w - 1; x >= 0; --x)  /* 0 -> w */
 405             *(data++) = current;
 406
 407         NEXT(y1);
 408     }
 409
 410
 411     for (y3 = (h / 2) - 1; y3 > 0; --y3) {
 412         current = COLOR(y3);
 413         for (x = w - 1; x >= 0; --x)
 414             *(data++) = current;
 415
 416         NEXT(y3);
 417     }
 418
 419     current = COLOR(y3);
 420     for (x = w - 1; x >= 0; --x)  /* 0 -> w */
 421         *(data++) = current;
 422
 423     RrColorFree(primary_light);
 424     RrColorFree(secondary_light);
 425 }
 426
 427 static void gradient_horizontal(RrSurface *sf, gint w, gint h)
 428 {
 429     gint x, y;
 430     RrPixel32 *data = sf->pixel_data, *datav;
 431     RrPixel32 current;
 432
 433     VARS(x);
 434     SETUP(x, sf->primary, sf->secondary, w);
 435
 436     for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 437         current = COLOR(x);
 438         datav = data;
 439         for (y = h - 1; y >= 0; --y) {  /* 0 -> h */
 440             *datav = current;
 441             datav += w;
 442         }
 443         ++data;
 444
 445         NEXT(x);
 446     }
 447     current = COLOR(x);
 448     for (y = h - 1; y >= 0; --y)  /* 0 -> h */
 449         *(data + y * w) = current;
 450 }
 451
 452 static void gradient_mirrorhorizontal(RrSurface *sf, gint w, gint h)
 453 {
 454     gint x, y;
 455     RrPixel32 *data = sf->pixel_data, *datav;
 456     RrPixel32 current;
 457
 458     VARS(x);
 459     SETUP(x, sf->primary, sf->secondary, w/2);
 460
 461     for (x = w - 1; x > w/2-1; --x) {  /* 0 -> w-1 */
 462         current = COLOR(x);
 463         datav = data;
 464         for (y = h - 1; y >= 0; --y) {  /* 0 -> h */
 465             *datav = current;
 466             datav += w;
 467         }
 468         ++data;
 469
 470         NEXT(x);
 471     }
 472     SETUP(x, sf->secondary, sf->primary, w/2);
 473     for (x = w/2 - 1; x > 0; --x) {  /* 0 -> w-1 */
 474         current = COLOR(x);
 475         datav = data;
 476         for (y = h - 1; y >= 0; --y) {  /* 0 -> h */
 477             *datav = current;
 478             datav += w;
 479         }
 480         ++data;
 481
 482         NEXT(x);
 483     }
 484     current = COLOR(x);
 485     for (y = h - 1; y >= 0; --y)  /* 0 -> h */
 486         *(data + y * w) = current;
 487 }
 488
 489 static void gradient_vertical(RrSurface *sf, gint w, gint h)
 490 {
 491     gint x, y;
 492     RrPixel32 *data = sf->pixel_data;
 493     RrPixel32 current;
 494
 495     VARS(y);
 496     SETUP(y, sf->primary, sf->secondary, h);
 497
 498     for (y = h - 1; y > 0; --y) {  /* 0 -> h-1 */
 499         current = COLOR(y);
 500         for (x = w - 1; x >= 0; --x)  /* 0 -> w */
 501             *(data++) = current;
 502
 503         NEXT(y);
 504     }
 505     current = COLOR(y);
 506     for (x = w - 1; x >= 0; --x)  /* 0 -> w */
 507         *(data++) = current;
 508 }
 509
 510
 511 static void gradient_diagonal(RrSurface *sf, gint w, gint h)
 512 {
 513     gint x, y;
 514     RrPixel32 *data = sf->pixel_data;
 515     RrColor left, right;
 516     RrColor extracorner;
 517
 518     VARS(lefty);
 519     VARS(righty);
 520     VARS(x);
 521
 522     extracorner.r = (sf->primary->r + sf->secondary->r) / 2;
 523     extracorner.g = (sf->primary->g + sf->secondary->g) / 2;
 524     extracorner.b = (sf->primary->b + sf->secondary->b) / 2;
 525
 526     SETUP(lefty, sf->primary, (&extracorner), h);
 527     SETUP(righty, (&extracorner), sf->secondary, h);
 528
 529     for (y = h - 1; y > 0; --y) {  /* 0 -> h-1 */
 530         COLOR_RR(lefty, (&left));
 531         COLOR_RR(righty, (&right));
 532
 533         SETUP(x, (&left), (&right), w);
 534
 535         for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 536             *(data++) = COLOR(x);
 537
 538             NEXT(x);
 539         }
 540         *(data++) = COLOR(x);
 541
 542         NEXT(lefty);
 543         NEXT(righty);
 544     }
 545     COLOR_RR(lefty, (&left));
 546     COLOR_RR(righty, (&right));
 547
 548     SETUP(x, (&left), (&right), w);
 549
 550     for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 551         *(data++) = COLOR(x);
 552
 553         NEXT(x);
 554     }
 555     *data = COLOR(x);
 556 }
 557
 558 static void gradient_crossdiagonal(RrSurface *sf, gint w, gint h)
 559 {
 560     gint x, y;
 561     RrPixel32 *data = sf->pixel_data;
 562     RrColor left, right;
 563     RrColor extracorner;
 564
 565     VARS(lefty);
 566     VARS(righty);
 567     VARS(x);
 568
 569     extracorner.r = (sf->primary->r + sf->secondary->r) / 2;
 570     extracorner.g = (sf->primary->g + sf->secondary->g) / 2;
 571     extracorner.b = (sf->primary->b + sf->secondary->b) / 2;
 572
 573     SETUP(lefty, (&extracorner), sf->secondary, h);
 574     SETUP(righty, sf->primary, (&extracorner), h);
 575
 576     for (y = h - 1; y > 0; --y) {  /* 0 -> h-1 */
 577         COLOR_RR(lefty, (&left));
 578         COLOR_RR(righty, (&right));
 579
 580         SETUP(x, (&left), (&right), w);
 581
 582         for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 583             *(data++) = COLOR(x);
 584
 585             NEXT(x);
 586         }
 587         *(data++) = COLOR(x);
 588
 589         NEXT(lefty);
 590         NEXT(righty);
 591     }
 592     COLOR_RR(lefty, (&left));
 593     COLOR_RR(righty, (&right));
 594
 595     SETUP(x, (&left), (&right), w);
 596
 597     for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 598         *(data++) = COLOR(x);
 599
 600         NEXT(x);
 601     }
 602     *data = COLOR(x);
 603 }
 604
 605 static void gradient_pyramid(RrSurface *sf, gint inw, gint inh)
 606 {
 607     gint x, y, w = (inw >> 1) + 1, h = (inh >> 1) + 1;
 608     RrPixel32 *data = sf->pixel_data;
 609     RrPixel32 *end = data + inw*inh - 1;
 610     RrPixel32 current;
 611     RrColor left, right;
 612     RrColor extracorner;
 613
 614     VARS(lefty);
 615     VARS(righty);
 616     VARS(x);
 617
 618     extracorner.r = (sf->primary->r + sf->secondary->r) / 2;
 619     extracorner.g = (sf->primary->g + sf->secondary->g) / 2;
 620     extracorner.b = (sf->primary->b + sf->secondary->b) / 2;
 621
 622     SETUP(lefty, (&extracorner), sf->secondary, h);
 623     SETUP(righty, sf->primary, (&extracorner), h);
 624
 625     for (y = h - 1; y > 0; --y) {  /* 0 -> h-1 */
 626         COLOR_RR(lefty, (&left));
 627         COLOR_RR(righty, (&right));
 628
 629         SETUP(x, (&left), (&right), w);
 630
 631         for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 632             current = COLOR(x);
 633             *(data+x) = current;
 634             *(data+inw-x) = current;
 635             *(end-x) = current;
 636             *(end-(inw-x)) = current;
 637
 638             NEXT(x);
 639         }
 640         current = COLOR(x);
 641         *(data+x) = current;
 642         *(data+inw-x) = current;
 643         *(end-x) = current;
 644         *(end-(inw-x)) = current;
 645
 646         data+=inw;
 647         end-=inw;
 648
 649         NEXT(lefty);
 650         NEXT(righty);
 651     }
 652     COLOR_RR(lefty, (&left));
 653     COLOR_RR(righty, (&right));
 654
 655     SETUP(x, (&left), (&right), w);
 656
 657     for (x = w - 1; x > 0; --x) {  /* 0 -> w-1 */
 658         current = COLOR(x);
 659         *(data+x) = current;
 660         *(data+inw-x) = current;
 661         *(end-x) = current;
 662         *(end-(inw-x)) = current;
 663
 664         NEXT(x);
 665     }
 666     current = COLOR(x);
 667     *(data+x) = current;
 668     *(data+inw-x) = current;
 669     *(end-x) = current;
 670     *(end-(inw-x)) = current;
 671 }
 672