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