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