git.hungrycats.org Git - xscreensaver/blob - hacks/distort.c

   1 /* -*- mode: C; tab-width: 4 -*-
   2  * xscreensaver, Copyright (c) 1992-2014 Jamie Zawinski <jwz@jwz.org>
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that
   7  * copyright notice and this permission notice appear in supporting
   8  * documentation.  No representations are made about the suitability of this
   9  * software for any purpose.  It is provided "as is" without express or
  10  * implied warranty.
  11  */
  12
  13 /* distort
  14  * by Jonas Munsin (jmunsin@iki.fi) and Jamie Zawinski <jwz@jwz.org>
  15  * TODO:
  16  *      -check the allocations in init_round_lense again, maybe make it possible again
  17  *       to use swamp without pre-allocating/calculating (although that
  18  *       makes it slower) - -swamp is memory hungry
  19  *      -more distortion matrices (fortunately, I'm out of ideas :)
  20  * Stuff that would be cool but probably too much of a resource hog:
  21  *      -some kind of interpolation to avoid jaggies
  22  *    -large speed values leaves the image distorted
  23  * program idea borrowed from a screensaver on a non-*NIX OS,
  24  *
  25  * 28 Sep 1999 Jonas Munsin (jmunsin@iki.fi)
  26  *    Added about 10x faster algortim for 8, 16 and 32 bpp (modifies pixels
  27  *    directly avoiding costly XPutPixle(XGetPixel()) calls, inspired by
  28  *    xwhirl made by horvai@clipper.ens.fr (Peter Horvai) and the XFree86
  29  *    Xlib sources.
  30  *    This piece of code is really horrible, but it works, and at the moment
  31  *    I don't have time or inspiration to fix something that works (knock
  32  *    on wood).
  33  * 08 Oct 1999 Jonas Munsin (jmunsin@iki.fi)
  34  *      Corrected several bugs causing references beyond allocated memory.
  35  */
  36
  37 #include <math.h>
  38 #include <time.h>
  39 #include "screenhack.h"
  40 /*#include <X11/Xmd.h>*/
  41
  42 #ifdef HAVE_XSHM_EXTENSION
  43 # include "xshm.h"
  44 #endif /* HAVE_XSHM_EXTENSION */
  45
  46 #define CARD32 unsigned int
  47 #define CARD16 unsigned short
  48 #define CARD8  unsigned char
  49
  50
  51 struct coo {
  52         int x;
  53         int y;
  54         int r, r_change;
  55         int xmove, ymove;
  56 };
  57
  58 struct state {
  59   Display *dpy;
  60   Window window;
  61
  62   struct coo xy_coo[10];
  63
  64   int delay, radius, speed, number, blackhole, vortex, magnify, reflect, slow;
  65   int duration;
  66   time_t start_time;
  67
  68   XWindowAttributes xgwa;
  69   GC gc;
  70   unsigned long black_pixel;
  71
  72   XImage *orig_map, *buffer_map;
  73   unsigned long *buffer_map_cache;
  74
  75   int ***from;
  76   int ****from_array;
  77   int *fast_from;
  78
  79   int bpp_size;
  80
  81 #ifdef HAVE_XSHM_EXTENSION
  82   Bool use_shm;
  83   XShmSegmentInfo shm_info;
  84 #endif /* HAVE_XSHM_EXTENSION */
  85
  86   void (*effect) (struct state *, int);
  87   void (*draw) (struct state *, int);
  88   void (*draw_routine) (struct state *st, XImage *, XImage *, int, int, int *);
  89
  90   async_load_state *img_loader;
  91   Pixmap pm;
  92 };
  93
  94
  95 static void move_lense(struct state *, int);
  96 static void swamp_thing(struct state *, int);
  97 static void new_rnd_coo(struct state *, int);
  98 static void init_round_lense(struct state *st);
  99 static void reflect_draw(struct state *, int);
 100 static void plain_draw(struct state *, int);
 101
 102 static void fast_draw_8 (struct state *st, XImage *, XImage *, int, int, int *);
 103 static void fast_draw_16(struct state *st, XImage *, XImage *, int, int, int *);
 104 static void fast_draw_32(struct state *st, XImage *, XImage *, int, int, int *);
 105 static void generic_draw(struct state *st, XImage *, XImage *, int, int, int *);
 106
 107
 108 static void distort_finish_loading (struct state *);
 109
 110 static void
 111 distort_reset (struct state *st)
 112 {
 113     char *s;
 114     int i;
 115
 116     st->start_time = 0;
 117
 118         XGetWindowAttributes (st->dpy, st->window, &st->xgwa);
 119
 120         st->delay = get_integer_resource(st->dpy, "delay", "Integer");
 121     st->duration = get_integer_resource (st->dpy, "duration", "Seconds");
 122         st->radius = get_integer_resource(st->dpy, "radius", "Integer");
 123         st->speed = get_integer_resource(st->dpy, "speed", "Integer");
 124         st->number = get_integer_resource(st->dpy, "number", "Integer");
 125
 126         st->blackhole = get_boolean_resource(st->dpy, "blackhole", "Boolean");
 127         st->vortex = get_boolean_resource(st->dpy, "vortex", "Boolean");
 128         st->magnify = get_boolean_resource(st->dpy, "magnify", "Boolean");
 129         st->reflect = get_boolean_resource(st->dpy, "reflect", "Boolean");
 130         st->slow = get_boolean_resource(st->dpy, "slow", "Boolean");
 131
 132     if (st->delay < 0) st->delay = 0;
 133     if (st->duration < 1) st->duration = 1;
 134
 135     st->effect = NULL;
 136     s = get_string_resource(st->dpy, "effect", "String");
 137         if (s && !strcasecmp(s,"swamp"))
 138       st->effect = &swamp_thing;
 139     else if (s && !strcasecmp(s,"bounce"))
 140       st->effect = &move_lense;
 141     else if (s && !strcasecmp(s,"none"))
 142       ;
 143     else if (s && *s)
 144       fprintf(stderr,"%s: bogus effect: %s\n", progname, s);
 145
 146         if (st->effect == NULL && st->radius == 0 && st->speed == 0 && st->number == 0
 147                 && !st->blackhole && !st->vortex && !st->magnify && !st->reflect) {
 148 /* if no cmdline options are given, randomly choose one of:
 149  * -radius 125 -number 4 -speed 1 -bounce
 150  * -radius 125 -number 4 -speed 1 -blackhole
 151  * -radius 125 -number 4 -speed 1 -vortex
 152  * -radius 125 -number 4 -speed 1 -vortex -magnify
 153  * -radius 125 -number 4 -speed 1 -vortex -magnify -blackhole
 154  * -radius 250 -number 1 -speed 2 -bounce
 155  * -radius 250 -number 1 -speed 2 -blackhole
 156  * -radius 250 -number 1 -speed 2 -vortex
 157  * -radius 250 -number 1 -speed 2 -vortex -magnify
 158  * -radius 250 -number 1 -speed 2 -vortex -magnify -blackhole
 159  * -radius 80 -number 1 -speed 2 -reflect
 160  * -radius 125 -number 3 -speed 2 -reflect
 161  * jwz: not these
 162  *   -radius 125 -number 4 -speed 2 -swamp
 163  *   -radius 125 -number 4 -speed 2 -swamp -blackhole
 164  *   -radius 125 -number 4 -speed 2 -swamp -vortex
 165  *   -radius 125 -number 4 -speed 2 -swamp -vortex -magnify
 166  *   -radius 125 -number 4 -speed 2 -swamp -vortex -magnify -blackhole
 167  */
 168
 169                 i = (random() % 12 /* 17 */);
 170
 171                 st->draw = &plain_draw;
 172
 173                 switch (i) {
 174                         case 0:
 175                                 st->radius=125;st->number=4;st->speed=1;
 176                                 st->effect=&move_lense;break;
 177                         case 1:
 178                                 st->radius=125;st->number=4;st->speed=1;st->blackhole=1;
 179                                 st->effect=&move_lense;break;
 180                         case 2:
 181                                 st->radius=125;st->number=4;st->speed=1;st->vortex=1;
 182                                 st->effect=&move_lense;break;
 183                         case 3:
 184                                 st->radius=125;st->number=4;st->speed=1;st->vortex=1;st->magnify=1;
 185                                 st->effect=&move_lense;break;
 186                         case 4:
 187                                 st->radius=125;st->number=4;st->speed=1;st->vortex=1;st->magnify=1;st->blackhole=1;
 188                                 st->effect=&move_lense;break;
 189                         case 5:
 190                                 st->radius=250;st->number=1;st->speed=2;
 191                                 st->effect=&move_lense;break;
 192                         case 6:
 193                                 st->radius=250;st->number=1;st->speed=2;st->blackhole=1;
 194                                 st->effect=&move_lense;break;
 195                         case 7:
 196                                 st->radius=250;st->number=1;st->speed=2;st->vortex=1;
 197                                 st->effect=&move_lense;break;
 198                         case 8:
 199                                 st->radius=250;st->number=1;st->speed=2;st->vortex=1;st->magnify=1;
 200                                 st->effect=&move_lense;break;
 201                         case 9:
 202                                 st->radius=250;st->number=1;st->speed=2;st->vortex=1;st->magnify=1;st->blackhole=1;
 203                                 st->effect=&move_lense;break;
 204
 205                         case 10:
 206                                 st->radius=80;st->number=1;st->speed=2;st->reflect=1;
 207                                 st->draw = &reflect_draw;st->effect = &move_lense;break;
 208                         case 11:
 209                                 st->radius=125;st->number=4;st->speed=2;st->reflect=1;
 210                                 st->draw = &reflect_draw;st->effect = &move_lense;break;
 211
 212 #if 0 /* jwz: not these */
 213                         case 12:
 214                                 st->radius=125;st->number=4;st->speed=2;
 215                                 effect=&swamp_thing;break;
 216                         case 13:
 217                                 st->radius=125;st->number=4;st->speed=2;st->blackhole=1;
 218                                 effect=&swamp_thing;break;
 219                         case 14:
 220                                 st->radius=125;st->number=4;st->speed=2;st->vortex=1;
 221                                 effect=&swamp_thing;break;
 222                         case 15:
 223                                 st->radius=125;st->number=4;st->speed=2;st->vortex=1;st->magnify=1;
 224                                 effect=&swamp_thing;break;
 225                         case 16:
 226                                 st->radius=125;st->number=4;st->speed=2;st->vortex=1;st->magnify=1;st->blackhole=1;
 227                                 effect=&swamp_thing;break;
 228 #endif
 229
 230             default:
 231                 abort(); break;
 232                 }
 233         }
 234
 235     /* never allow the radius to be too close to the min window dimension
 236      */
 237     if (st->radius > st->xgwa.width  * 0.3) st->radius = st->xgwa.width  * 0.3;
 238     if (st->radius > st->xgwa.height * 0.3) st->radius = st->xgwa.height * 0.3;
 239
 240
 241     /* -swamp mode consumes vast amounts of memory, proportional to radius --
 242        so throttle radius to a small-ish value (60 => ~30MB.)
 243      */
 244     if (st->effect == &swamp_thing && st->radius > 60)
 245       st->radius = 60;
 246
 247         if (st->delay < 0)
 248                 st->delay = 0;
 249         if (st->radius <= 0)
 250                 st->radius = 60;
 251         if (st->speed <= 0)
 252                 st->speed = 2;
 253         if (st->number <= 0)
 254                 st->number=1;
 255         if (st->number >= 10)
 256                 st->number=1;
 257         if (st->effect == NULL)
 258                 st->effect = &move_lense;
 259         if (st->reflect) {
 260                 st->draw = &reflect_draw;
 261                 st->effect = &move_lense;
 262         }
 263         if (st->draw == NULL)
 264                 st->draw = &plain_draw;
 265 }
 266
 267 static void *
 268 distort_init (Display *dpy, Window window)
 269 {
 270   struct state *st = (struct state *) calloc (1, sizeof(*st));
 271         XGCValues gcv;
 272         long gcflags;
 273
 274     st->dpy = dpy;
 275     st->window = window;
 276
 277 #ifdef HAVE_XSHM_EXTENSION
 278         st->use_shm = get_boolean_resource(st->dpy, "useSHM", "Boolean");
 279 #endif /* HAVE_XSHM_EXTENSION */
 280
 281     distort_reset (st);
 282
 283         st->black_pixel = BlackPixelOfScreen( st->xgwa.screen );
 284
 285         gcv.function = GXcopy;
 286         gcv.subwindow_mode = IncludeInferiors;
 287         gcflags = GCFunction;
 288         if (use_subwindow_mode_p(st->xgwa.screen, st->window)) /* see grabscreen.c */
 289                 gcflags |= GCSubwindowMode;
 290         st->gc = XCreateGC (st->dpy, st->window, gcflags, &gcv);
 291
 292     /* On MacOS X11, XGetImage on a Window often gets an inexplicable BadMatch,
 293        possibly due to the window manager having occluded something?  It seems
 294        nondeterministic. Loading the image into a pixmap instead fixes it. */
 295     if (st->pm) XFreePixmap (st->dpy, st->pm);
 296     st->pm = XCreatePixmap (st->dpy, st->window,
 297                             st->xgwa.width, st->xgwa.height, st->xgwa.depth);
 298
 299     st->img_loader = load_image_async_simple (0, st->xgwa.screen, st->window,
 300                                               st->pm, 0, 0);
 301     st->start_time = time ((time_t *) 0);
 302     return st;
 303 }
 304
 305 static void
 306 distort_finish_loading (struct state *st)
 307 {
 308     int i;
 309
 310     st->start_time = time ((time_t *) 0);
 311
 312         st->buffer_map = 0;
 313     if (! st->pm) abort();
 314     XClearWindow (st->dpy, st->window);
 315     XCopyArea (st->dpy, st->pm, st->window, st->gc,
 316                0, 0, st->xgwa.width, st->xgwa.height, 0, 0);
 317         st->orig_map = XGetImage(st->dpy, st->pm, 0, 0,
 318                              st->xgwa.width, st->xgwa.height,
 319                              ~0L, ZPixmap);
 320         st->buffer_map_cache = malloc(sizeof(unsigned long)*(2*st->radius+st->speed+2)*(2*st->radius+st->speed+2));
 321
 322         if (st->buffer_map_cache == NULL) {
 323                 perror("distort");
 324                 exit(EXIT_FAILURE);
 325         }
 326
 327 # ifdef HAVE_XSHM_EXTENSION
 328
 329         if (st->use_shm)
 330           {
 331                 st->buffer_map = create_xshm_image(st->dpy, st->xgwa.visual, st->orig_map->depth,
 332                                                                            ZPixmap, 0, &st->shm_info,
 333                                                                            2*st->radius + st->speed + 2,
 334                                                                            2*st->radius + st->speed + 2);
 335                 if (!st->buffer_map)
 336                   st->use_shm = False;
 337           }
 338 # endif /* HAVE_XSHM_EXTENSION */
 339
 340         if (!st->buffer_map)
 341           {
 342                 st->buffer_map = XCreateImage(st->dpy, st->xgwa.visual,
 343                                                                   st->orig_map->depth, ZPixmap, 0, 0,
 344                                                                   2*st->radius + st->speed + 2, 2*st->radius + st->speed + 2,
 345                                                                   8, 0);
 346                 st->buffer_map->data = (char *)
 347                   calloc(st->buffer_map->height, st->buffer_map->bytes_per_line);
 348         }
 349
 350         if ((st->buffer_map->byte_order == st->orig_map->byte_order)
 351                         && (st->buffer_map->depth == st->orig_map->depth)
 352                         && (st->buffer_map->format == ZPixmap)
 353                         && (st->orig_map->format == ZPixmap)
 354                         && !st->slow) {
 355                 switch (st->orig_map->bits_per_pixel) {
 356                         case 32:
 357                                 st->draw_routine = &fast_draw_32;
 358                                 st->bpp_size = sizeof(CARD32);
 359                                 break;
 360                         case 16:
 361                                 st->draw_routine = &fast_draw_16;
 362                                 st->bpp_size = sizeof(CARD16);
 363                                 break;
 364                         case 8:
 365                                 st->draw_routine = &fast_draw_8;
 366                                 st->bpp_size = sizeof(CARD8);
 367                                 break;
 368                         default:
 369                                 st->draw_routine = &generic_draw;
 370                                 break;
 371                 }
 372         } else {
 373                 st->draw_routine = &generic_draw;
 374         }
 375         init_round_lense(st);
 376
 377         for (i = 0; i < st->number; i++) {
 378                 new_rnd_coo(st,i);
 379                 if (st->number != 1)
 380                         st->xy_coo[i].r = (i*st->radius)/(st->number-1); /* "randomize" initial */
 381                 else
 382                          st->xy_coo[i].r = 0;
 383                 st->xy_coo[i].r_change = st->speed + (i%2)*2*(-st->speed);      /* values a bit */
 384                 st->xy_coo[i].xmove = st->speed + (i%2)*2*(-st->speed);
 385                 st->xy_coo[i].ymove = st->speed + (i%2)*2*(-st->speed);
 386         }
 387 }
 388
 389 /* example: initializes a "see-trough" matrix */
 390 /* static void make_null_lense(struct state *st)
 391 {
 392         int i, j;
 393         for (i = 0; i < 2*radius+speed+2; i++) {
 394                 for (j = 0 ; j < 2*radius+speed+2 ; j++) {
 395                         from[i][j][0]=i;
 396                         from[i][j][1]=j;
 397                 }
 398         }
 399 }
 400 */
 401 static void convert(struct state *st)
 402 {
 403         int *p;
 404         int i, j;
 405         st->fast_from = calloc(1, sizeof(int)*((st->buffer_map->bytes_per_line/st->bpp_size)*(2*st->radius+st->speed+2) + 2*st->radius+st->speed+2));
 406         if (st->fast_from == NULL) {
 407                 perror("distort");
 408                 exit(EXIT_FAILURE);
 409         }
 410         p = st->fast_from;
 411         for (i = 0; i < 2*st->radius+st->speed+2; i++) {
 412                 for (j = 0; j < 2*st->radius+st->speed+2; j++) {
 413                         *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size)
 414                                 = st->from[i][j][0] + st->xgwa.width*st->from[i][j][1];
 415                         if (*(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) < 0
 416                                         || *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) >= st->orig_map->height*st->orig_map->width) {
 417                                 *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) = 0;
 418                         }
 419                 }
 420         }
 421 }
 422
 423 /* makes a lense with the Radius=loop and centred in
 424  * the point (radius, radius)
 425  */
 426 static void make_round_lense(struct state *st, int radius, int loop)
 427 {
 428         int i, j;
 429
 430         for (i = 0; i < 2*radius+st->speed+2; i++) {
 431                 for(j = 0; j < ((0 == st->bpp_size) ? (2*radius+st->speed+2) : (st->buffer_map->bytes_per_line/st->bpp_size)); j++) {
 432                         double r, d;
 433                         r = sqrt ((i-radius)*(i-radius)+(j-radius)*(j-radius));
 434                         if (loop == 0)
 435                           d=0.0;
 436                         else
 437                           d=r/loop;
 438
 439                         if (r < loop-1) {
 440
 441                                 if (st->vortex) { /* vortex-twist effect */
 442                                         double angle;
 443                 /* this one-line formula for getting a nice rotation angle is borrowed
 444                  * (with permission) from the whirl plugin for gimp,
 445                  * Copyright (C) 1996 Federico Mena Quintero
 446                  */
 447                 /* 5 is just a constant used because it looks good :) */
 448                                         angle = 5*(1-d)*(1-d);
 449
 450         /* Avoid atan2: DOMAIN error message */
 451                                         if ((radius-j) == 0.0 && (radius-i) == 0.0) {
 452                                                 st->from[i][j][0] = radius + cos(angle)*r;
 453                                                 st->from[i][j][1] = radius + sin(angle)*r;
 454                                         } else {
 455                                                 st->from[i][j][0] = radius +
 456                                                         cos(angle - atan2(radius-j, -(radius-i)))*r;
 457                                                 st->from[i][j][1] = radius +
 458                                                         sin(angle - atan2(radius-j, -(radius-i)))*r;
 459                                         }
 460                                         if (st->magnify) {
 461                                                 r = sin(d*M_PI_2);
 462                                                 if (st->blackhole && r != 0) /* blackhole effect */
 463                                                         r = 1/r;
 464                                                 st->from[i][j][0] = radius + (st->from[i][j][0]-radius)*r;
 465                                                 st->from[i][j][1] = radius + (st->from[i][j][1]-radius)*r;
 466                                         }
 467                                 } else { /* default is to magnify */
 468                                         r = sin(d*M_PI_2);
 469
 470         /* raising r to different power here gives different amounts of
 471          * distortion, a negative value sucks everything into a black hole
 472          */
 473                                 /*      r = r*r; */
 474                                         if (st->blackhole && r != 0) /* blackhole effect */
 475                                                 r = 1/r;
 476                                                                         /* bubble effect (and blackhole) */
 477                                         st->from[i][j][0] = radius + (i-radius)*r;
 478                                         st->from[i][j][1] = radius + (j-radius)*r;
 479                                 }
 480                         } else { /* not inside loop */
 481                                 st->from[i][j][0] = i;
 482                                 st->from[i][j][1] = j;
 483                         }
 484                 }
 485         }
 486
 487         /* this is really just a quick hack to keep both the compability mode with all depths and still
 488          * allow the custom optimized draw routines with the minimum amount of work */
 489         if (0 != st->bpp_size) {
 490                 convert(st);
 491         }
 492 }
 493
 494 #ifndef EXIT_FAILURE
 495 # define EXIT_FAILURE -1
 496 #endif
 497
 498 static void allocate_lense(struct state *st)
 499 {
 500         int i, j;
 501         int s = ((0 != st->bpp_size) ? (st->buffer_map->bytes_per_line/st->bpp_size) : (2*st->radius+st->speed+2));
 502         /* maybe this should be redone so that from[][][] is in one block;
 503          * then pointers could be used instead of arrays in some places (and
 504          * maybe give a speedup - maybe also consume less memory)
 505          */
 506         st->from = (int ***)malloc(s*sizeof(int **));
 507         if (st->from == NULL) {
 508                 perror("distort");
 509                 exit(EXIT_FAILURE);
 510         }
 511         for (i = 0; i < s; i++) {
 512                 st->from[i] = (int **)malloc((2*st->radius+st->speed+2) * sizeof(int *));
 513                 if (st->from[i] == NULL) {
 514                         perror("distort");
 515                         exit(EXIT_FAILURE);
 516                 }
 517                 for (j = 0; j < s; j++) {
 518                         st->from[i][j] = (int *)malloc(2 * sizeof(int));
 519                         if (st->from[i][j] == NULL) {
 520                                 perror("distort");
 521                                 exit(EXIT_FAILURE);
 522                         }
 523                 }
 524         }
 525 }
 526
 527 /* from_array in an array containing precalculated from matrices,
 528  * this is a double faced mem vs speed trade, it's faster, but eats
 529  * _a lot_ of mem for large radius (is there a bug here? I can't see it)
 530  */
 531 static void init_round_lense(struct state *st)
 532 {
 533         int k;
 534
 535         if (st->effect == &swamp_thing) {
 536                 st->from_array = (int ****)malloc((st->radius+1)*sizeof(int ***));
 537                 for (k=0; k <= st->radius; k++) {
 538                         allocate_lense(st);
 539                         make_round_lense(st, st->radius, k);
 540                         st->from_array[k] = st->from;
 541                 }
 542         } else { /* just allocate one from[][][] */
 543                 allocate_lense(st);
 544                 make_round_lense(st, st->radius,st->radius);
 545         }
 546 }
 547
 548 /* If fast_draw_8, fast_draw_16 or fast_draw_32 are to be used, the following properties
 549  * of the src and dest XImages must hold (otherwise the generic, slooow, method provided
 550  * by X is to be used):
 551  *      src->byte_order == dest->byte_order
 552  *      src->format == ZPixmap && dest->format == ZPixmap
 553  *      src->depth == dest->depth == the depth the function in question asumes
 554  * x and y is the coordinates in src from where to cut out the image from,
 555  * distort_matrix is a precalculated array of how to distort the matrix
 556  */
 557
 558 static void fast_draw_8(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 559 {
 560         CARD8 *u = (CARD8 *)dest->data;
 561         CARD8 *t = (CARD8 *)src->data + x + y*src->bytes_per_line/sizeof(CARD8);
 562
 563         while (u < (CARD8 *)(dest->data + sizeof(CARD8)*dest->height
 564                                 *dest->bytes_per_line/sizeof(CARD8))) {
 565                 *u++ = t[*distort_matrix++];
 566         }
 567 }
 568
 569 static void fast_draw_16(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 570 {
 571         CARD16 *u = (CARD16 *)dest->data;
 572         CARD16 *t = (CARD16 *)src->data + x + y*src->bytes_per_line/sizeof(CARD16);
 573
 574         while (u < (CARD16 *)(dest->data + sizeof(CARD16)*dest->height
 575                                 *dest->bytes_per_line/sizeof(CARD16))) {
 576                 *u++ = t[*distort_matrix++];
 577         }
 578 }
 579
 580 static void fast_draw_32(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 581 {
 582         CARD32 *u = (CARD32 *)dest->data;
 583         CARD32 *t = (CARD32 *)src->data + x + y*src->bytes_per_line/sizeof(CARD32);
 584
 585         while (u < (CARD32 *)(dest->data + sizeof(CARD32)*dest->height
 586                                 *dest->bytes_per_line/sizeof(CARD32))) {
 587                 *u++ = t[*distort_matrix++];
 588         }
 589 }
 590
 591 static void generic_draw(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 592 {
 593         int i, j;
 594         for (i = 0; i < dest->width; i++)
 595                 for (j = 0; j < dest->height; j++)
 596                         if (st->from[i][j][0] + x >= 0 &&
 597                                         st->from[i][j][0] + x < src->width &&
 598                                         st->from[i][j][1] + y >= 0 &&
 599                                         st->from[i][j][1] + y < src->height)
 600                                 XPutPixel(dest, i, j,
 601                                                 XGetPixel(src,
 602                                                         st->from[i][j][0] + x,
 603                                                         st->from[i][j][1] + y));
 604 }
 605
 606 /* generate an XImage of from[][][] and draw it on the screen */
 607 static void plain_draw(struct state *st, int k)
 608 {
 609         if (st->xy_coo[k].x+2*st->radius+st->speed+2 > st->orig_map->width ||
 610                         st->xy_coo[k].y+2*st->radius+st->speed+2 > st->orig_map->height)
 611                 return;
 612
 613         st->draw_routine(st, st->orig_map, st->buffer_map, st->xy_coo[k].x, st->xy_coo[k].y, st->fast_from);
 614
 615 # ifdef HAVE_XSHM_EXTENSION
 616         if (st->use_shm)
 617                 XShmPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 618                                 2*st->radius+st->speed+2, 2*st->radius+st->speed+2, False);
 619         else
 620
 621         if (!st->use_shm)
 622 # endif
 623                 XPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 624                                 2*st->radius+st->speed+2, 2*st->radius+st->speed+2);
 625
 626 }
 627
 628
 629 /* generate an XImage from the reflect algoritm submitted by
 630  * Randy Zack <randy@acucorp.com>
 631  * draw really got too big and ugly so I split it up
 632  * it should be possible to use the from[][] to speed it up
 633  * (once I figure out the algorithm used :)
 634  */
 635 static void reflect_draw(struct state *st, int k)
 636 {
 637         int i, j;
 638         int     cx, cy;
 639         int     ly, lysq, lx, ny, dist, rsq = st->radius * st->radius;
 640
 641         cx = cy = st->radius;
 642         if (st->xy_coo[k].ymove > 0)
 643                 cy += st->speed;
 644         if (st->xy_coo[k].xmove > 0)
 645                 cx += st->speed;
 646
 647         for(i = 0 ; i < 2*st->radius+st->speed+2; i++) {
 648                 ly = i - cy;
 649                 lysq = ly * ly;
 650                 ny = st->xy_coo[k].y + i;
 651                 if (ny >= st->orig_map->height) ny = st->orig_map->height-1;
 652                 for(j = 0 ; j < 2*st->radius+st->speed+2 ; j++) {
 653                         lx = j - cx;
 654                         dist = lx * lx + lysq;
 655                         if (dist > rsq ||
 656                                 ly < -st->radius || ly > st->radius ||
 657                                 lx < -st->radius || lx > st->radius)
 658                                 XPutPixel( st->buffer_map, j, i,
 659                                                    XGetPixel( st->orig_map, st->xy_coo[k].x + j, ny ));
 660                         else if (dist == 0)
 661                                 XPutPixel( st->buffer_map, j, i, st->black_pixel );
 662                         else {
 663                                 int     x = st->xy_coo[k].x + cx + (lx * rsq / dist);
 664                                 int     y = st->xy_coo[k].y + cy + (ly * rsq / dist);
 665                                 if (x < 0 || x >= st->xgwa.width ||
 666                                         y < 0 || y >= st->xgwa.height)
 667                                         XPutPixel( st->buffer_map, j, i, st->black_pixel );
 668                                 else
 669                                         XPutPixel( st->buffer_map, j, i,
 670                                                            XGetPixel( st->orig_map, x, y ));
 671                         }
 672                 }
 673         }
 674
 675         XPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 676                         2*st->radius+st->speed+2, 2*st->radius+st->speed+2);
 677 }
 678
 679 /* create a new, random coordinate, that won't interfer with any other
 680  * coordinates, as the drawing routines would be significantly slowed
 681  * down if they were to handle serveral layers of distortions
 682  */
 683 static void new_rnd_coo(struct state *st, int k)
 684 {
 685         int i;
 686     int loop = 0;
 687
 688         st->xy_coo[k].x = (random() % (st->xgwa.width-2*st->radius));
 689         st->xy_coo[k].y = (random() % (st->xgwa.height-2*st->radius));
 690
 691         for (i = 0; i < st->number; i++) {
 692                 if (i != k) {
 693                         if ((abs(st->xy_coo[k].x - st->xy_coo[i].x) <= 2*st->radius+st->speed+2)
 694                          && (abs(st->xy_coo[k].y - st->xy_coo[i].y) <= 2*st->radius+st->speed+2)) {
 695                                 st->xy_coo[k].x = (random() % (st->xgwa.width-2*st->radius));
 696                                 st->xy_coo[k].y = (random() % (st->xgwa.height-2*st->radius));
 697                                 i=-1; /* ugly */
 698                         }
 699                 }
 700         if (loop++ > 1000) return;  /* let's not get stuck */
 701         }
 702 }
 703
 704 /* move lens and handle bounces with walls and other lenses */
 705 static void move_lense(struct state *st, int k)
 706 {
 707         int i;
 708
 709         if (st->xy_coo[k].x + 2*st->radius + st->speed + 2 >= st->xgwa.width)
 710                 st->xy_coo[k].xmove = -abs(st->xy_coo[k].xmove);
 711         if (st->xy_coo[k].x <= st->speed)
 712                 st->xy_coo[k].xmove = abs(st->xy_coo[k].xmove);
 713         if (st->xy_coo[k].y + 2*st->radius + st->speed + 2 >= st->xgwa.height)
 714                 st->xy_coo[k].ymove = -abs(st->xy_coo[k].ymove);
 715         if (st->xy_coo[k].y <= st->speed)
 716                 st->xy_coo[k].ymove = abs(st->xy_coo[k].ymove);
 717
 718         st->xy_coo[k].x = st->xy_coo[k].x + st->xy_coo[k].xmove;
 719         st->xy_coo[k].y = st->xy_coo[k].y + st->xy_coo[k].ymove;
 720
 721         /* bounce against othe lenses */
 722         for (i = 0; i < st->number; i++) {
 723                 if ((i != k)
 724
 725 /* This commented test is for rectangular lenses (not currently used) and
 726  * the one used is for circular ones
 727                 && (abs(xy_coo[k].x - xy_coo[i].x) <= 2*radius)
 728                 && (abs(xy_coo[k].y - xy_coo[i].y) <= 2*radius)) { */
 729
 730                 && ((st->xy_coo[k].x - st->xy_coo[i].x)*(st->xy_coo[k].x - st->xy_coo[i].x)
 731                   + (st->xy_coo[k].y - st->xy_coo[i].y)*(st->xy_coo[k].y - st->xy_coo[i].y)
 732                         <= 2*st->radius*2*st->radius)) {
 733
 734                         int x, y;
 735                         x = st->xy_coo[k].xmove;
 736                         y = st->xy_coo[k].ymove;
 737                         st->xy_coo[k].xmove = st->xy_coo[i].xmove;
 738                         st->xy_coo[k].ymove = st->xy_coo[i].ymove;
 739                         st->xy_coo[i].xmove = x;
 740                         st->xy_coo[i].ymove = y;
 741                 }
 742         }
 743
 744 }
 745
 746 /* make xy_coo[k] grow/shrink */
 747 static void swamp_thing(struct state *st, int k)
 748 {
 749         if (st->xy_coo[k].r >= st->radius)
 750                 st->xy_coo[k].r_change = -abs(st->xy_coo[k].r_change);
 751
 752         if (st->xy_coo[k].r <= 0) {
 753                 st->from = st->from_array[0];
 754                 st->draw(st,k);
 755                 st->xy_coo[k].r_change = abs(st->xy_coo[k].r_change);
 756                 new_rnd_coo(st,k);
 757                 st->xy_coo[k].r=st->xy_coo[k].r_change;
 758                 return;
 759         }
 760
 761         st->xy_coo[k].r = st->xy_coo[k].r + st->xy_coo[k].r_change;
 762
 763         if (st->xy_coo[k].r >= st->radius)
 764                 st->xy_coo[k].r = st->radius;
 765         if (st->xy_coo[k].r <= 0)
 766                 st->xy_coo[k].r=0;
 767
 768         st->from = st->from_array[st->xy_coo[k].r];
 769 }
 770
 771
 772 static unsigned long
 773 distort_draw (Display *dpy, Window window, void *closure)
 774 {
 775   struct state *st = (struct state *) closure;
 776   int k;
 777
 778   if (st->img_loader)   /* still loading */
 779     {
 780       st->img_loader = load_image_async_simple (st->img_loader, 0, 0, 0, 0, 0);
 781       if (! st->img_loader) {  /* just finished */
 782         distort_finish_loading (st);
 783       }
 784       return st->delay;
 785     }
 786
 787   if (!st->img_loader &&
 788       st->start_time + st->duration < time ((time_t *) 0)) {
 789     if (st->pm) XFreePixmap (st->dpy, st->pm);
 790     st->pm = XCreatePixmap (st->dpy, st->window,
 791                             st->xgwa.width, st->xgwa.height, st->xgwa.depth);
 792     st->img_loader = load_image_async_simple (0, st->xgwa.screen, st->window,
 793                                               st->pm, 0, 0);
 794     return st->delay;
 795   }
 796
 797   for (k = 0; k < st->number; k++) {
 798     st->effect(st,k);
 799     st->draw(st,k);
 800   }
 801   return st->delay;
 802 }
 803
 804 static void
 805 distort_reshape (Display *dpy, Window window, void *closure,
 806                  unsigned int w, unsigned int h)
 807 {
 808   struct state *st = (struct state *) closure;
 809   XGetWindowAttributes (st->dpy, st->window, &st->xgwa);
 810   /* XClearWindow (dpy, window); */
 811   /* Why doesn't this work? */
 812   if (st->orig_map)  /* created in distort_finish_loading, might be early */
 813     XPutImage (st->dpy, st->window, st->gc, st->orig_map,
 814                0, 0, st->orig_map->width, st->orig_map->height, 0, 0);
 815 }
 816
 817 static Bool
 818 distort_event (Display *dpy, Window window, void *closure, XEvent *event)
 819 {
 820   struct state *st = (struct state *) closure;
 821   if (screenhack_event_helper (dpy, window, event))
 822     {
 823       distort_reset(st);
 824       return True;
 825     }
 826   return False;
 827 }
 828
 829 static void
 830 distort_free (Display *dpy, Window window, void *closure)
 831 {
 832   struct state *st = (struct state *) closure;
 833   XFreeGC (st->dpy, st->gc);
 834   if (st->pm) XFreePixmap (dpy, st->pm);
 835   if (st->orig_map) XDestroyImage (st->orig_map);
 836   if (st->buffer_map) XDestroyImage (st->buffer_map);
 837   if (st->from) free (st->from);
 838   if (st->fast_from) free (st->fast_from);
 839   if (st->from_array) free (st->from_array);
 840   free (st);
 841 }
 842
 843
 844 \f
 845
 846 static const char *distort_defaults [] = {
 847         "*dontClearRoot:                True",
 848         "*background:                   Black",
 849     "*fpsSolid:                         true",
 850 #ifdef __sgi    /* really, HAVE_READ_DISPLAY_EXTENSION */
 851         "*visualID:                     Best",
 852 #endif
 853
 854         "*delay:                        20000",
 855     "*duration:                 120",
 856         "*radius:                       0",
 857         "*speed:                        0",
 858         "*number:                       0",
 859         "*slow:                         False",
 860         "*vortex:                       False",
 861         "*magnify:                      False",
 862         "*reflect:                      False",
 863         "*blackhole:            False",
 864         "*effect:                   none",
 865 #ifdef HAVE_XSHM_EXTENSION
 866         "*useSHM:                       False",         /* xshm turns out not to help. */
 867 #endif /* HAVE_XSHM_EXTENSION */
 868 #ifdef HAVE_MOBILE
 869   "*ignoreRotation:     True",
 870   "*rotateImages:       True",
 871 #endif
 872         0
 873 };
 874
 875 static XrmOptionDescRec distort_options [] = {
 876   { "-delay",     ".delay",       XrmoptionSepArg, 0 },
 877   { "-duration",  ".duration",    XrmoptionSepArg, 0 },
 878   { "-radius",    ".radius",      XrmoptionSepArg, 0 },
 879   { "-speed",     ".speed",       XrmoptionSepArg, 0 },
 880   { "-number",    ".number",      XrmoptionSepArg, 0 },
 881
 882   { "-effect",    ".effect",      XrmoptionSepArg, 0 },
 883   { "-swamp",     ".effect",      XrmoptionNoArg, "swamp"  },
 884   { "-bounce",    ".effect",      XrmoptionNoArg, "bounce" },
 885
 886   { "-reflect",   ".reflect",     XrmoptionNoArg, "True" },
 887   { "-vortex",    ".vortex",      XrmoptionNoArg, "True" },
 888   { "-magnify",   ".magnify",     XrmoptionNoArg, "True" },
 889   { "-blackhole", ".blackhole",   XrmoptionNoArg, "True" },
 890   { "-slow",      ".slow",        XrmoptionNoArg, "True" },
 891 #ifdef HAVE_XSHM_EXTENSION
 892   { "-shm",       ".useSHM",      XrmoptionNoArg, "True" },
 893   { "-no-shm",    ".useSHM",      XrmoptionNoArg, "False" },
 894 #endif /* HAVE_XSHM_EXTENSION */
 895   { 0, 0, 0, 0 }
 896 };
 897
 898 XSCREENSAVER_MODULE ("Distort", distort)