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

   1 /* -*- mode: C; tab-width: 4 -*-
   2  * xscreensaver, Copyright (c) 1992-2008 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 50 -number 4 -speed 1 -bounce
 156  * -radius 50 -number 4 -speed 1 -blackhole
 157  * -radius 50 -number 4 -speed 1 -vortex
 158  * -radius 50 -number 4 -speed 1 -vortex -magnify
 159  * -radius 50 -number 4 -speed 1 -vortex -magnify -blackhole
 160  * -radius 100 -number 1 -speed 2 -bounce
 161  * -radius 100 -number 1 -speed 2 -blackhole
 162  * -radius 100 -number 1 -speed 2 -vortex
 163  * -radius 100 -number 1 -speed 2 -vortex -magnify
 164  * -radius 100 -number 1 -speed 2 -vortex -magnify -blackhole
 165  * -radius 80 -number 1 -speed 2 -reflect
 166  * -radius 50 -number 3 -speed 2 -reflect
 167  * jwz: not these
 168  *   -radius 50 -number 4 -speed 2 -swamp
 169  *   -radius 50 -number 4 -speed 2 -swamp -blackhole
 170  *   -radius 50 -number 4 -speed 2 -swamp -vortex
 171  *   -radius 50 -number 4 -speed 2 -swamp -vortex -magnify
 172  *   -radius 50 -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=50;st->number=4;st->speed=1;
 182                                 st->effect=&move_lense;break;
 183                         case 1:
 184                                 st->radius=50;st->number=4;st->speed=1;st->blackhole=1;
 185                                 st->effect=&move_lense;break;
 186                         case 2:
 187                                 st->radius=50;st->number=4;st->speed=1;st->vortex=1;
 188                                 st->effect=&move_lense;break;
 189                         case 3:
 190                                 st->radius=50;st->number=4;st->speed=1;st->vortex=1;st->magnify=1;
 191                                 st->effect=&move_lense;break;
 192                         case 4:
 193                                 st->radius=50;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=100;st->number=1;st->speed=2;
 197                                 st->effect=&move_lense;break;
 198                         case 6:
 199                                 st->radius=100;st->number=1;st->speed=2;st->blackhole=1;
 200                                 st->effect=&move_lense;break;
 201                         case 7:
 202                                 st->radius=100;st->number=1;st->speed=2;st->vortex=1;
 203                                 st->effect=&move_lense;break;
 204                         case 8:
 205                                 st->radius=100;st->number=1;st->speed=2;st->vortex=1;st->magnify=1;
 206                                 st->effect=&move_lense;break;
 207                         case 9:
 208                                 st->radius=100;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=50;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=50;st->number=4;st->speed=2;
 221                                 effect=&swamp_thing;break;
 222                         case 13:
 223                                 st->radius=50;st->number=4;st->speed=2;st->blackhole=1;
 224                                 effect=&swamp_thing;break;
 225                         case 14:
 226                                 st->radius=50;st->number=4;st->speed=2;st->vortex=1;
 227                                 effect=&swamp_thing;break;
 228                         case 15:
 229                                 st->radius=50;st->number=4;st->speed=2;st->vortex=1;st->magnify=1;
 230                                 effect=&swamp_thing;break;
 231                         case 16:
 232                                 st->radius=50;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         /* but if the window is small, reduce default radius */
 241         if (st->xgwa.width < st->radius * 8)
 242           st->radius = st->xgwa.width/8;
 243         }
 244
 245     /* never allow the radius to be too close to the min window dimension
 246      */
 247     if (st->radius >= st->xgwa.width  * 0.45) st->radius = st->xgwa.width  * 0.45;
 248     if (st->radius >= st->xgwa.height * 0.45) st->radius = st->xgwa.height * 0.45;
 249
 250
 251     /* -swamp mode consumes vast amounts of memory, proportional to radius --
 252        so throttle radius to a small-ish value (60 => ~30MB.)
 253      */
 254     if (st->effect == &swamp_thing && st->radius > 60)
 255       st->radius = 60;
 256
 257         if (st->delay < 0)
 258                 st->delay = 0;
 259         if (st->radius <= 0)
 260                 st->radius = 60;
 261         if (st->speed <= 0)
 262                 st->speed = 2;
 263         if (st->number <= 0)
 264                 st->number=1;
 265         if (st->number >= 10)
 266                 st->number=1;
 267         if (st->effect == NULL)
 268                 st->effect = &move_lense;
 269         if (st->reflect) {
 270                 st->draw = &reflect_draw;
 271                 st->effect = &move_lense;
 272         }
 273         if (st->draw == NULL)
 274                 st->draw = &plain_draw;
 275
 276         st->black_pixel = BlackPixelOfScreen( st->xgwa.screen );
 277
 278         gcv.function = GXcopy;
 279         gcv.subwindow_mode = IncludeInferiors;
 280         gcflags = GCFunction;
 281         if (use_subwindow_mode_p(st->xgwa.screen, st->window)) /* see grabscreen.c */
 282                 gcflags |= GCSubwindowMode;
 283         st->gc = XCreateGC (st->dpy, st->window, gcflags, &gcv);
 284
 285     st->img_loader = load_image_async_simple (0, st->xgwa.screen, st->window,
 286                                               st->window, 0, 0);
 287     st->start_time = time ((time_t) 0);
 288     return st;
 289 }
 290
 291 static void
 292 distort_finish_loading (struct state *st)
 293 {
 294     int i;
 295
 296     st->start_time = time ((time_t) 0);
 297
 298         st->buffer_map = 0;
 299         st->orig_map = XGetImage(st->dpy, st->window, 0, 0, st->xgwa.width, st->xgwa.height,
 300                                                  ~0L, ZPixmap);
 301         st->buffer_map_cache = malloc(sizeof(unsigned long)*(2*st->radius+st->speed+2)*(2*st->radius+st->speed+2));
 302
 303         if (st->buffer_map_cache == NULL) {
 304                 perror("distort");
 305                 exit(EXIT_FAILURE);
 306         }
 307
 308 # ifdef HAVE_XSHM_EXTENSION
 309
 310         if (st->use_shm)
 311           {
 312                 st->buffer_map = create_xshm_image(st->dpy, st->xgwa.visual, st->orig_map->depth,
 313                                                                            ZPixmap, 0, &st->shm_info,
 314                                                                            2*st->radius + st->speed + 2,
 315                                                                            2*st->radius + st->speed + 2);
 316                 if (!st->buffer_map)
 317                   st->use_shm = False;
 318           }
 319 # endif /* HAVE_XSHM_EXTENSION */
 320
 321         if (!st->buffer_map)
 322           {
 323                 st->buffer_map = XCreateImage(st->dpy, st->xgwa.visual,
 324                                                                   st->orig_map->depth, ZPixmap, 0, 0,
 325                                                                   2*st->radius + st->speed + 2, 2*st->radius + st->speed + 2,
 326                                                                   8, 0);
 327                 st->buffer_map->data = (char *)
 328                   calloc(st->buffer_map->height, st->buffer_map->bytes_per_line);
 329         }
 330
 331         if ((st->buffer_map->byte_order == st->orig_map->byte_order)
 332                         && (st->buffer_map->depth == st->orig_map->depth)
 333                         && (st->buffer_map->format == ZPixmap)
 334                         && (st->orig_map->format == ZPixmap)
 335                         && !st->slow) {
 336                 switch (st->orig_map->bits_per_pixel) {
 337                         case 32:
 338                                 st->draw_routine = &fast_draw_32;
 339                                 st->bpp_size = sizeof(CARD32);
 340                                 break;
 341                         case 16:
 342                                 st->draw_routine = &fast_draw_16;
 343                                 st->bpp_size = sizeof(CARD16);
 344                                 break;
 345                         case 8:
 346                                 st->draw_routine = &fast_draw_8;
 347                                 st->bpp_size = sizeof(CARD8);
 348                                 break;
 349                         default:
 350                                 st->draw_routine = &generic_draw;
 351                                 break;
 352                 }
 353         } else {
 354                 st->draw_routine = &generic_draw;
 355         }
 356         init_round_lense(st);
 357
 358         for (i = 0; i < st->number; i++) {
 359                 new_rnd_coo(st,i);
 360                 if (st->number != 1)
 361                         st->xy_coo[i].r = (i*st->radius)/(st->number-1); /* "randomize" initial */
 362                 else
 363                          st->xy_coo[i].r = 0;
 364                 st->xy_coo[i].r_change = st->speed + (i%2)*2*(-st->speed);      /* values a bit */
 365                 st->xy_coo[i].xmove = st->speed + (i%2)*2*(-st->speed);
 366                 st->xy_coo[i].ymove = st->speed + (i%2)*2*(-st->speed);
 367         }
 368 }
 369
 370 /* example: initializes a "see-trough" matrix */
 371 /* static void make_null_lense(struct state *st)
 372 {
 373         int i, j;
 374         for (i = 0; i < 2*radius+speed+2; i++) {
 375                 for (j = 0 ; j < 2*radius+speed+2 ; j++) {
 376                         from[i][j][0]=i;
 377                         from[i][j][1]=j;
 378                 }
 379         }
 380 }
 381 */
 382 static void convert(struct state *st)
 383 {
 384         int *p;
 385         int i, j;
 386         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));
 387         if (st->fast_from == NULL) {
 388                 perror("distort");
 389                 exit(EXIT_FAILURE);
 390         }
 391         p = st->fast_from;
 392         for (i = 0; i < 2*st->radius+st->speed+2; i++) {
 393                 for (j = 0; j < 2*st->radius+st->speed+2; j++) {
 394                         *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size)
 395                                 = st->from[i][j][0] + st->xgwa.width*st->from[i][j][1];
 396                         if (*(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) < 0
 397                                         || *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) >= st->orig_map->height*st->orig_map->width) {
 398                                 *(p + i + j*st->buffer_map->bytes_per_line/st->bpp_size) = 0;
 399                         }
 400                 }
 401         }
 402 }
 403
 404 /* makes a lense with the Radius=loop and centred in
 405  * the point (radius, radius)
 406  */
 407 static void make_round_lense(struct state *st, int radius, int loop)
 408 {
 409         int i, j;
 410
 411         for (i = 0; i < 2*radius+st->speed+2; i++) {
 412                 for(j = 0; j < ((0 == st->bpp_size) ? (2*radius+st->speed+2) : (st->buffer_map->bytes_per_line/st->bpp_size)); j++) {
 413                         double r, d;
 414                         r = sqrt ((i-radius)*(i-radius)+(j-radius)*(j-radius));
 415                         if (loop == 0)
 416                           d=0.0;
 417                         else
 418                           d=r/loop;
 419
 420                         if (r < loop-1) {
 421
 422                                 if (st->vortex) { /* vortex-twist effect */
 423                                         double angle;
 424                 /* this one-line formula for getting a nice rotation angle is borrowed
 425                  * (with permission) from the whirl plugin for gimp,
 426                  * Copyright (C) 1996 Federico Mena Quintero
 427                  */
 428                 /* 5 is just a constant used because it looks good :) */
 429                                         angle = 5*(1-d)*(1-d);
 430
 431         /* Avoid atan2: DOMAIN error message */
 432                                         if ((radius-j) == 0.0 && (radius-i) == 0.0) {
 433                                                 st->from[i][j][0] = radius + cos(angle)*r;
 434                                                 st->from[i][j][1] = radius + sin(angle)*r;
 435                                         } else {
 436                                                 st->from[i][j][0] = radius +
 437                                                         cos(angle - atan2(radius-j, -(radius-i)))*r;
 438                                                 st->from[i][j][1] = radius +
 439                                                         sin(angle - atan2(radius-j, -(radius-i)))*r;
 440                                         }
 441                                         if (st->magnify) {
 442                                                 r = sin(d*M_PI_2);
 443                                                 if (st->blackhole && r != 0) /* blackhole effect */
 444                                                         r = 1/r;
 445                                                 st->from[i][j][0] = radius + (st->from[i][j][0]-radius)*r;
 446                                                 st->from[i][j][1] = radius + (st->from[i][j][1]-radius)*r;
 447                                         }
 448                                 } else { /* default is to magnify */
 449                                         r = sin(d*M_PI_2);
 450
 451         /* raising r to different power here gives different amounts of
 452          * distortion, a negative value sucks everything into a black hole
 453          */
 454                                 /*      r = r*r; */
 455                                         if (st->blackhole && r != 0) /* blackhole effect */
 456                                                 r = 1/r;
 457                                                                         /* bubble effect (and blackhole) */
 458                                         st->from[i][j][0] = radius + (i-radius)*r;
 459                                         st->from[i][j][1] = radius + (j-radius)*r;
 460                                 }
 461                         } else { /* not inside loop */
 462                                 st->from[i][j][0] = i;
 463                                 st->from[i][j][1] = j;
 464                         }
 465                 }
 466         }
 467
 468         /* this is really just a quick hack to keep both the compability mode with all depths and still
 469          * allow the custom optimized draw routines with the minimum amount of work */
 470         if (0 != st->bpp_size) {
 471                 convert(st);
 472         }
 473 }
 474
 475 #ifndef EXIT_FAILURE
 476 # define EXIT_FAILURE -1
 477 #endif
 478
 479 static void allocate_lense(struct state *st)
 480 {
 481         int i, j;
 482         int s = ((0 != st->bpp_size) ? (st->buffer_map->bytes_per_line/st->bpp_size) : (2*st->radius+st->speed+2));
 483         /* maybe this should be redone so that from[][][] is in one block;
 484          * then pointers could be used instead of arrays in some places (and
 485          * maybe give a speedup - maybe also consume less memory)
 486          */
 487         st->from = (int ***)malloc(s*sizeof(int **));
 488         if (st->from == NULL) {
 489                 perror("distort");
 490                 exit(EXIT_FAILURE);
 491         }
 492         for (i = 0; i < s; i++) {
 493                 st->from[i] = (int **)malloc((2*st->radius+st->speed+2) * sizeof(int *));
 494                 if (st->from[i] == NULL) {
 495                         perror("distort");
 496                         exit(EXIT_FAILURE);
 497                 }
 498                 for (j = 0; j < s; j++) {
 499                         st->from[i][j] = (int *)malloc(2 * sizeof(int));
 500                         if (st->from[i][j] == NULL) {
 501                                 perror("distort");
 502                                 exit(EXIT_FAILURE);
 503                         }
 504                 }
 505         }
 506 }
 507
 508 /* from_array in an array containing precalculated from matrices,
 509  * this is a double faced mem vs speed trade, it's faster, but eats
 510  * _a lot_ of mem for large radius (is there a bug here? I can't see it)
 511  */
 512 static void init_round_lense(struct state *st)
 513 {
 514         int k;
 515
 516         if (st->effect == &swamp_thing) {
 517                 st->from_array = (int ****)malloc((st->radius+1)*sizeof(int ***));
 518                 for (k=0; k <= st->radius; k++) {
 519                         allocate_lense(st);
 520                         make_round_lense(st, st->radius, k);
 521                         st->from_array[k] = st->from;
 522                 }
 523         } else { /* just allocate one from[][][] */
 524                 allocate_lense(st);
 525                 make_round_lense(st, st->radius,st->radius);
 526         }
 527 }
 528
 529 /* If fast_draw_8, fast_draw_16 or fast_draw_32 are to be used, the following properties
 530  * of the src and dest XImages must hold (otherwise the generic, slooow, method provided
 531  * by X is to be used):
 532  *      src->byte_order == dest->byte_order
 533  *      src->format == ZPixmap && dest->format == ZPixmap
 534  *      src->depth == dest->depth == the depth the function in question asumes
 535  * x and y is the coordinates in src from where to cut out the image from,
 536  * distort_matrix is a precalculated array of how to distort the matrix
 537  */
 538
 539 static void fast_draw_8(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 540 {
 541         CARD8 *u = (CARD8 *)dest->data;
 542         CARD8 *t = (CARD8 *)src->data + x + y*src->bytes_per_line/sizeof(CARD8);
 543
 544         while (u < (CARD8 *)(dest->data + sizeof(CARD8)*dest->height
 545                                 *dest->bytes_per_line/sizeof(CARD8))) {
 546                 *u++ = t[*distort_matrix++];
 547         }
 548 }
 549
 550 static void fast_draw_16(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 551 {
 552         CARD16 *u = (CARD16 *)dest->data;
 553         CARD16 *t = (CARD16 *)src->data + x + y*src->bytes_per_line/sizeof(CARD16);
 554
 555         while (u < (CARD16 *)(dest->data + sizeof(CARD16)*dest->height
 556                                 *dest->bytes_per_line/sizeof(CARD16))) {
 557                 *u++ = t[*distort_matrix++];
 558         }
 559 }
 560
 561 static void fast_draw_32(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 562 {
 563         CARD32 *u = (CARD32 *)dest->data;
 564         CARD32 *t = (CARD32 *)src->data + x + y*src->bytes_per_line/sizeof(CARD32);
 565
 566         while (u < (CARD32 *)(dest->data + sizeof(CARD32)*dest->height
 567                                 *dest->bytes_per_line/sizeof(CARD32))) {
 568                 *u++ = t[*distort_matrix++];
 569         }
 570 }
 571
 572 static void generic_draw(struct state *st, XImage *src, XImage *dest, int x, int y, int *distort_matrix)
 573 {
 574         int i, j;
 575         for (i = 0; i < dest->width; i++)
 576                 for (j = 0; j < dest->height; j++)
 577                         if (st->from[i][j][0] + x >= 0 &&
 578                                         st->from[i][j][0] + x < src->width &&
 579                                         st->from[i][j][1] + y >= 0 &&
 580                                         st->from[i][j][1] + y < src->height)
 581                                 XPutPixel(dest, i, j,
 582                                                 XGetPixel(src,
 583                                                         st->from[i][j][0] + x,
 584                                                         st->from[i][j][1] + y));
 585 }
 586
 587 /* generate an XImage of from[][][] and draw it on the screen */
 588 static void plain_draw(struct state *st, int k)
 589 {
 590         if (st->xy_coo[k].x+2*st->radius+st->speed+2 > st->orig_map->width ||
 591                         st->xy_coo[k].y+2*st->radius+st->speed+2 > st->orig_map->height)
 592                 return;
 593
 594         st->draw_routine(st, st->orig_map, st->buffer_map, st->xy_coo[k].x, st->xy_coo[k].y, st->fast_from);
 595
 596 # ifdef HAVE_XSHM_EXTENSION
 597         if (st->use_shm)
 598                 XShmPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 599                                 2*st->radius+st->speed+2, 2*st->radius+st->speed+2, False);
 600         else
 601
 602         if (!st->use_shm)
 603 # endif
 604                 XPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 605                                 2*st->radius+st->speed+2, 2*st->radius+st->speed+2);
 606
 607 }
 608
 609
 610 /* generate an XImage from the reflect algoritm submitted by
 611  * Randy Zack <randy@acucorp.com>
 612  * draw really got too big and ugly so I split it up
 613  * it should be possible to use the from[][] to speed it up
 614  * (once I figure out the algorithm used :)
 615  */
 616 static void reflect_draw(struct state *st, int k)
 617 {
 618         int i, j;
 619         int     cx, cy;
 620         int     ly, lysq, lx, ny, dist, rsq = st->radius * st->radius;
 621
 622         cx = cy = st->radius;
 623         if (st->xy_coo[k].ymove > 0)
 624                 cy += st->speed;
 625         if (st->xy_coo[k].xmove > 0)
 626                 cx += st->speed;
 627
 628         for(i = 0 ; i < 2*st->radius+st->speed+2; i++) {
 629                 ly = i - cy;
 630                 lysq = ly * ly;
 631                 ny = st->xy_coo[k].y + i;
 632                 if (ny >= st->orig_map->height) ny = st->orig_map->height-1;
 633                 for(j = 0 ; j < 2*st->radius+st->speed+2 ; j++) {
 634                         lx = j - cx;
 635                         dist = lx * lx + lysq;
 636                         if (dist > rsq ||
 637                                 ly < -st->radius || ly > st->radius ||
 638                                 lx < -st->radius || lx > st->radius)
 639                                 XPutPixel( st->buffer_map, j, i,
 640                                                    XGetPixel( st->orig_map, st->xy_coo[k].x + j, ny ));
 641                         else if (dist == 0)
 642                                 XPutPixel( st->buffer_map, j, i, st->black_pixel );
 643                         else {
 644                                 int     x = st->xy_coo[k].x + cx + (lx * rsq / dist);
 645                                 int     y = st->xy_coo[k].y + cy + (ly * rsq / dist);
 646                                 if (x < 0 || x >= st->xgwa.width ||
 647                                         y < 0 || y >= st->xgwa.height)
 648                                         XPutPixel( st->buffer_map, j, i, st->black_pixel );
 649                                 else
 650                                         XPutPixel( st->buffer_map, j, i,
 651                                                            XGetPixel( st->orig_map, x, y ));
 652                         }
 653                 }
 654         }
 655
 656         XPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, st->xy_coo[k].x, st->xy_coo[k].y,
 657                         2*st->radius+st->speed+2, 2*st->radius+st->speed+2);
 658 }
 659
 660 /* create a new, random coordinate, that won't interfer with any other
 661  * coordinates, as the drawing routines would be significantly slowed
 662  * down if they were to handle serveral layers of distortions
 663  */
 664 static void new_rnd_coo(struct state *st, int k)
 665 {
 666         int i;
 667
 668         st->xy_coo[k].x = (random() % (st->xgwa.width-2*st->radius));
 669         st->xy_coo[k].y = (random() % (st->xgwa.height-2*st->radius));
 670
 671         for (i = 0; i < st->number; i++) {
 672                 if (i != k) {
 673                         if ((abs(st->xy_coo[k].x - st->xy_coo[i].x) <= 2*st->radius+st->speed+2)
 674                          && (abs(st->xy_coo[k].y - st->xy_coo[i].y) <= 2*st->radius+st->speed+2)) {
 675                                 st->xy_coo[k].x = (random() % (st->xgwa.width-2*st->radius));
 676                                 st->xy_coo[k].y = (random() % (st->xgwa.height-2*st->radius));
 677                                 i=-1; /* ugly */
 678                         }
 679                 }
 680         }
 681 }
 682
 683 /* move lens and handle bounces with walls and other lenses */
 684 static void move_lense(struct state *st, int k)
 685 {
 686         int i;
 687
 688         if (st->xy_coo[k].x + 2*st->radius + st->speed + 2 >= st->xgwa.width)
 689                 st->xy_coo[k].xmove = -abs(st->xy_coo[k].xmove);
 690         if (st->xy_coo[k].x <= st->speed)
 691                 st->xy_coo[k].xmove = abs(st->xy_coo[k].xmove);
 692         if (st->xy_coo[k].y + 2*st->radius + st->speed + 2 >= st->xgwa.height)
 693                 st->xy_coo[k].ymove = -abs(st->xy_coo[k].ymove);
 694         if (st->xy_coo[k].y <= st->speed)
 695                 st->xy_coo[k].ymove = abs(st->xy_coo[k].ymove);
 696
 697         st->xy_coo[k].x = st->xy_coo[k].x + st->xy_coo[k].xmove;
 698         st->xy_coo[k].y = st->xy_coo[k].y + st->xy_coo[k].ymove;
 699
 700         /* bounce against othe lenses */
 701         for (i = 0; i < st->number; i++) {
 702                 if ((i != k)
 703
 704 /* This commented test is for rectangular lenses (not currently used) and
 705  * the one used is for circular ones
 706                 && (abs(xy_coo[k].x - xy_coo[i].x) <= 2*radius)
 707                 && (abs(xy_coo[k].y - xy_coo[i].y) <= 2*radius)) { */
 708
 709                 && ((st->xy_coo[k].x - st->xy_coo[i].x)*(st->xy_coo[k].x - st->xy_coo[i].x)
 710                   + (st->xy_coo[k].y - st->xy_coo[i].y)*(st->xy_coo[k].y - st->xy_coo[i].y)
 711                         <= 2*st->radius*2*st->radius)) {
 712
 713                         int x, y;
 714                         x = st->xy_coo[k].xmove;
 715                         y = st->xy_coo[k].ymove;
 716                         st->xy_coo[k].xmove = st->xy_coo[i].xmove;
 717                         st->xy_coo[k].ymove = st->xy_coo[i].ymove;
 718                         st->xy_coo[i].xmove = x;
 719                         st->xy_coo[i].ymove = y;
 720                 }
 721         }
 722
 723 }
 724
 725 /* make xy_coo[k] grow/shrink */
 726 static void swamp_thing(struct state *st, int k)
 727 {
 728         if (st->xy_coo[k].r >= st->radius)
 729                 st->xy_coo[k].r_change = -abs(st->xy_coo[k].r_change);
 730
 731         if (st->xy_coo[k].r <= 0) {
 732                 st->from = st->from_array[0];
 733                 st->draw(st,k);
 734                 st->xy_coo[k].r_change = abs(st->xy_coo[k].r_change);
 735                 new_rnd_coo(st,k);
 736                 st->xy_coo[k].r=st->xy_coo[k].r_change;
 737                 return;
 738         }
 739
 740         st->xy_coo[k].r = st->xy_coo[k].r + st->xy_coo[k].r_change;
 741
 742         if (st->xy_coo[k].r >= st->radius)
 743                 st->xy_coo[k].r = st->radius;
 744         if (st->xy_coo[k].r <= 0)
 745                 st->xy_coo[k].r=0;
 746
 747         st->from = st->from_array[st->xy_coo[k].r];
 748 }
 749
 750
 751 static unsigned long
 752 distort_draw (Display *dpy, Window window, void *closure)
 753 {
 754   struct state *st = (struct state *) closure;
 755   int k;
 756
 757   if (st->img_loader)   /* still loading */
 758     {
 759       st->img_loader = load_image_async_simple (st->img_loader, 0, 0, 0, 0, 0);
 760       if (! st->img_loader) {  /* just finished */
 761         distort_finish_loading (st);
 762       }
 763       return st->delay;
 764     }
 765
 766   if (!st->img_loader &&
 767       st->start_time + st->duration < time ((time_t) 0)) {
 768     st->img_loader = load_image_async_simple (0, st->xgwa.screen, st->window,
 769                                               st->window, 0, 0);
 770     return st->delay;
 771   }
 772
 773   for (k = 0; k < st->number; k++) {
 774     st->effect(st,k);
 775     st->draw(st,k);
 776   }
 777   return st->delay;
 778 }
 779
 780 static void
 781 distort_reshape (Display *dpy, Window window, void *closure,
 782                  unsigned int w, unsigned int h)
 783 {
 784 }
 785
 786 static Bool
 787 distort_event (Display *dpy, Window window, void *closure, XEvent *event)
 788 {
 789   return False;
 790 }
 791
 792 static void
 793 distort_free (Display *dpy, Window window, void *closure)
 794 {
 795   struct state *st = (struct state *) closure;
 796   XFreeGC (st->dpy, st->gc);
 797   if (st->orig_map) XDestroyImage (st->orig_map);
 798   if (st->buffer_map) XDestroyImage (st->buffer_map);
 799   if (st->from) free (st->from);
 800   if (st->fast_from) free (st->fast_from);
 801   if (st->from_array) free (st->from_array);
 802   free (st);
 803 }
 804
 805
 806 \f
 807
 808 static const char *distort_defaults [] = {
 809         "*dontClearRoot:                True",
 810         "*background:                   Black",
 811     "*fpsSolid:                         true",
 812 #ifdef __sgi    /* really, HAVE_READ_DISPLAY_EXTENSION */
 813         "*visualID:                     Best",
 814 #endif
 815
 816         "*delay:                        20000",
 817     "*duration:                 120",
 818         "*radius:                       0",
 819         "*speed:                        0",
 820         "*number:                       0",
 821         "*slow:                         False",
 822         "*vortex:                       False",
 823         "*magnify:                      False",
 824         "*reflect:                      False",
 825         "*blackhole:            False",
 826         "*effect:                   none",
 827 #ifdef HAVE_XSHM_EXTENSION
 828         "*useSHM:                       False",         /* xshm turns out not to help. */
 829 #endif /* HAVE_XSHM_EXTENSION */
 830         0
 831 };
 832
 833 static XrmOptionDescRec distort_options [] = {
 834   { "-delay",     ".delay",       XrmoptionSepArg, 0 },
 835   { "-duration",  ".duration",    XrmoptionSepArg, 0 },
 836   { "-radius",    ".radius",      XrmoptionSepArg, 0 },
 837   { "-speed",     ".speed",       XrmoptionSepArg, 0 },
 838   { "-number",    ".number",      XrmoptionSepArg, 0 },
 839
 840   { "-effect",    ".effect",      XrmoptionSepArg, 0 },
 841   { "-swamp",     ".effect",      XrmoptionNoArg, "swamp"  },
 842   { "-bounce",    ".effect",      XrmoptionNoArg, "bounce" },
 843
 844   { "-reflect",   ".reflect",     XrmoptionNoArg, "True" },
 845   { "-vortex",    ".vortex",      XrmoptionNoArg, "True" },
 846   { "-magnify",   ".magnify",     XrmoptionNoArg, "True" },
 847   { "-blackhole", ".blackhole",   XrmoptionNoArg, "True" },
 848   { "-slow",      ".slow",        XrmoptionNoArg, "True" },
 849 #ifdef HAVE_XSHM_EXTENSION
 850   { "-shm",       ".useSHM",      XrmoptionNoArg, "True" },
 851   { "-no-shm",    ".useSHM",      XrmoptionNoArg, "False" },
 852 #endif /* HAVE_XSHM_EXTENSION */
 853   { 0, 0, 0, 0 }
 854 };
 855
 856 XSCREENSAVER_MODULE ("Distort", distort)