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

   1 /* -*- Mode: C; tab-width: 4 -*- */
   2 /* slip --- lots of slipping blits */
   3
   4 #if 0
   5 static const char sccsid[] = "@(#)slip.c        5.00 2000/11/01 xlockmore";
   6 #endif
   7
   8 /*-
   9  * Copyright (c) 1992 by Scott Draves <spot@cs.cmu.edu>
  10  *
  11  * Permission to use, copy, modify, and distribute this software and its
  12  * documentation for any purpose and without fee is hereby granted,
  13  * provided that the above copyright notice appear in all copies and that
  14  * both that copyright notice and this permission notice appear in
  15  * supporting documentation.
  16  *
  17  * This file is provided AS IS with no warranties of any kind.  The author
  18  * shall have no liability with respect to the infringement of copyrights,
  19  * trade secrets or any patents by this file or any part thereof.  In no
  20  * event will the author be liable for any lost revenue or profits or
  21  * other special, indirect and consequential damages.
  22  *
  23  * 01-Nov-2000: Allocation checks
  24  * 10-May-1997: Jamie Zawinski <jwz@jwz.org> compatible with xscreensaver
  25  * 01-Dec-1995: Patched for VMS <joukj@hrem.stm.tudelft.nl>
  26  */
  27
  28 #ifdef STANDALONE
  29 # define MODE_slip
  30 # define DEFAULTS       "*delay: 50000 \n" \
  31                                         "*count: 35 \n" \
  32                                         "*cycles: 50 \n" \
  33                                         "*ncolors: 200 \n"
  34
  35 # define refresh_slip 0
  36 # define slip_handle_event 0
  37 # include "xlockmore.h"         /* in xscreensaver distribution */
  38 #else /* STANDALONE */
  39 # include "xlock.h"             /* in xlockmore distribution */
  40 #endif /* STANDALONE */
  41
  42 #ifdef MODE_slip
  43
  44 ENTRYPOINT ModeSpecOpt slip_opts =
  45 {0, (XrmOptionDescRec *) NULL, 0, (argtype *) NULL, (OptionStruct *) NULL};
  46
  47 #ifdef USE_MODULES
  48 ModStruct   slip_description =
  49 {"slip", "init_slip", "draw_slip", "release_slip",
  50  "init_slip", "init_slip", (char *) NULL, &slip_opts,
  51  50000, 35, 50, 1, 64, 1.0, "",
  52  "Shows slipping blits", 0, NULL};
  53
  54 #endif
  55
  56 typedef struct {
  57         int         width, height;
  58         int         nblits_remaining;
  59         int         blit_width, blit_height;
  60         int         mode;
  61         int         first_time;
  62         int         backwards;
  63         short       lasthalf;
  64         int         stage;
  65         unsigned long r;
  66     Bool image_loading_p;
  67 } slipstruct;
  68 static slipstruct *slips = (slipstruct *) NULL;
  69
  70 static short
  71 halfrandom(slipstruct *sp, int mv)
  72 {
  73         unsigned long r;
  74
  75         if (sp->lasthalf) {
  76                 r = sp->lasthalf;
  77                 sp->lasthalf = 0;
  78         } else {
  79                 r = LRAND();
  80                 sp->lasthalf = (short) (r >> 16);
  81         }
  82         return r % mv;
  83 }
  84
  85 static int
  86 erandom(slipstruct *sp, int mv)
  87 {
  88         int         res;
  89
  90         if (0 == sp->stage) {
  91                 sp->r = LRAND();
  92                 sp->stage = 7;
  93         }
  94         res = (int) (sp->r & 0xf);
  95         sp->r = sp->r >> 4;
  96         sp->stage--;
  97         if (res & 8)
  98                 return res & mv;
  99         else
 100                 return -(res & mv);
 101 }
 102
 103 #ifdef STANDALONE
 104 static void
 105 image_loaded_cb (Screen *screen, Window w, Drawable d,
 106                  const char *name, XRectangle *geom,
 107                  void *closure)
 108 {
 109   ModeInfo *mi = (ModeInfo *) closure;
 110   slipstruct *sp = &slips[MI_SCREEN(mi)];
 111   Display *dpy = DisplayOfScreen (screen);
 112   XCopyArea (dpy, d, w, mi->gc, 0, 0,
 113              sp->width, sp->height, 0, 0);
 114   XFreePixmap (dpy, d);
 115   sp->image_loading_p = False;
 116 }
 117 #endif /* STANDALONE */
 118
 119 static void
 120 prepare_screen(ModeInfo * mi, slipstruct * sp)
 121 {
 122
 123         Display    *display = MI_DISPLAY(mi);
 124         GC          gc = MI_GC(mi);
 125         int         i, n, w = sp->width / 20;
 126         int         not_solid = halfrandom(sp, 10);
 127
 128         sp->backwards = (int) (LRAND() & 1);    /* jwz: go the other way sometimes */
 129
 130         if (sp->first_time || !halfrandom(sp, 10)) {
 131                 MI_CLEARWINDOW(mi);
 132                 n = 300;
 133         } else {
 134                 if (halfrandom(sp, 5))
 135                         return;
 136                 if (halfrandom(sp, 5))
 137                         n = 100;
 138                 else
 139                         n = 2000;
 140         }
 141
 142         if (MI_NPIXELS(mi) > 2)
 143                 XSetForeground(display, gc, MI_PIXEL(mi, halfrandom(sp, MI_NPIXELS(mi))));
 144         else if (halfrandom(sp, 2))
 145                 XSetForeground(display, gc, MI_WHITE_PIXEL(mi));
 146         else
 147                 XSetForeground(display, gc, MI_BLACK_PIXEL(mi));
 148
 149         for (i = 0; i < n; i++) {
 150                 int         ww = ((w / 2) + halfrandom(sp, MAX(w, 1)));
 151
 152                 if (not_solid) {
 153                         if (MI_NPIXELS(mi) > 2)
 154                                 XSetForeground(display, gc, MI_PIXEL(mi, halfrandom(sp, MI_NPIXELS(mi))));
 155                         else if (halfrandom(sp, 2))
 156                                 XSetForeground(display, gc, MI_WHITE_PIXEL(mi));
 157                         else
 158                                 XSetForeground(display, gc, MI_BLACK_PIXEL(mi));
 159                 }
 160                 XFillRectangle(display, MI_WINDOW(mi), gc,
 161                                halfrandom(sp, MAX(sp->width - ww, 1)),
 162                                halfrandom(sp, MAX(sp->height - ww, 1)),
 163                                ww, ww);
 164         }
 165         sp->first_time = 0;
 166
 167
 168 #ifdef STANDALONE                         /* jwz -- sometimes hack the desktop image! */
 169         if (!sp->image_loading_p &&
 170         (1||halfrandom(sp, 2) == 0)) {
 171       /* Load it into a pixmap so that the "Loading" message and checkerboard
 172          don't show up on the window -- we keep running while the image is
 173          in progress... */
 174       Pixmap p = XCreatePixmap (MI_DISPLAY(mi), MI_WINDOW(mi),
 175                                 sp->width, sp->height, mi->xgwa.depth);
 176       sp->image_loading_p = True;
 177       load_image_async (ScreenOfDisplay (MI_DISPLAY(mi), 0/*####MI_SCREEN(mi)*/),
 178                         MI_WINDOW(mi), p, image_loaded_cb, mi);
 179         }
 180 #endif
 181 }
 182
 183 static int
 184 quantize(double d)
 185 {
 186         int         i = (int) floor(d);
 187         double      f = d - i;
 188
 189         if ((LRAND() & 0xff) < f * 0xff)
 190                 i++;
 191         return i;
 192 }
 193
 194 ENTRYPOINT void
 195 reshape_slip (ModeInfo * mi, int w, int h)
 196 {
 197   slipstruct *sp = &slips[MI_SCREEN(mi)];
 198   sp->width = w;
 199   sp->height = h;
 200   sp->blit_width = sp->width / 25;
 201   sp->blit_height = sp->height / 25;
 202
 203   sp->mode = 0;
 204   sp->nblits_remaining = 0;
 205 }
 206
 207 ENTRYPOINT void
 208 init_slip (ModeInfo * mi)
 209 {
 210         slipstruct *sp;
 211
 212         if (slips == NULL) {
 213                 if ((slips = (slipstruct *) calloc(MI_NUM_SCREENS(mi),
 214                                                sizeof (slipstruct))) == NULL)
 215                         return;
 216         }
 217         sp = &slips[MI_SCREEN(mi)];
 218
 219         sp->nblits_remaining = 0;
 220         sp->mode = 0;
 221         sp->first_time = 1;
 222
 223         /* no "NoExpose" events from XCopyArea wanted */
 224         XSetGraphicsExposures(MI_DISPLAY(mi), MI_GC(mi), False);
 225
 226     reshape_slip (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
 227 }
 228
 229 ENTRYPOINT void
 230 draw_slip (ModeInfo * mi)
 231 {
 232         Display    *display = MI_DISPLAY(mi);
 233         Window      window = MI_WINDOW(mi);
 234         GC          gc = MI_GC(mi);
 235         int         timer;
 236         slipstruct *sp;
 237
 238         if (slips == NULL)
 239                 return;
 240         sp = &slips[MI_SCREEN(mi)];
 241
 242         timer = MI_COUNT(mi) * MI_CYCLES(mi);
 243
 244         MI_IS_DRAWN(mi) = True;
 245
 246         while (timer--) {
 247                 int         xi = halfrandom(sp, MAX(sp->width - sp->blit_width, 1));
 248                 int         yi = halfrandom(sp, MAX(sp->height - sp->blit_height, 1));
 249                 double      x, y, dx = 0, dy = 0, t, s1, s2;
 250
 251                 if (0 == sp->nblits_remaining--) {
 252                         static const int lut[] = {0, 0, 0, 1, 1, 1, 2};
 253
 254                         prepare_screen(mi, sp);
 255                         sp->nblits_remaining = MI_COUNT(mi) *
 256                                 (2000 + halfrandom(sp, 1000) + halfrandom(sp, 1000));
 257                         if (sp->mode == 2)
 258                                 sp->mode = halfrandom(sp, 2);
 259                         else
 260                                 sp->mode = lut[halfrandom(sp, 7)];
 261                 }
 262                 x = (2 * xi + sp->blit_width) / (double) sp->width - 1;
 263                 y = (2 * yi + sp->blit_height) / (double) sp->height - 1;
 264
 265                 /* (x,y) is in biunit square */
 266                 switch (sp->mode) {
 267                         case 0: /* rotor */
 268                                 dx = x;
 269                                 dy = y;
 270
 271                                 if (dy < 0) {
 272                                         dy += 0.04;
 273                                         if (dy > 0)
 274                                                 dy = 0.00;
 275                                 }
 276                                 if (dy > 0) {
 277                                         dy -= 0.04;
 278                                         if (dy < 0)
 279                                                 dy = 0.00;
 280                                 }
 281                                 t = dx * dx + dy * dy + 1e-10;
 282                                 s1 = 2 * dx * dx / t - 1;
 283                                 s2 = 2 * dx * dy / t;
 284                                 dx = s1 * 5;
 285                                 dy = s2 * 5;
 286
 287                                 if (sp->backwards) {    /* jwz: go the other way sometimes */
 288                                         dx = -dx;
 289                                         dy = -dy;
 290                                 }
 291                                 break;
 292                         case 1: /* shuffle */
 293                                 dx = erandom(sp, 3);
 294                                 dy = erandom(sp, 3);
 295                                 break;
 296                         case 2: /* explode */
 297                                 dx = x * 3;
 298                                 dy = y * 3;
 299                                 break;
 300                 }
 301                 {
 302                         int         qx = xi + quantize(dx), qy = yi + quantize(dy);
 303                         int         wrap;
 304
 305                         if (qx < 0 || qy < 0 ||
 306                             qx >= sp->width - sp->blit_width ||
 307                             qy >= sp->height - sp->blit_height)
 308                                 continue;
 309
 310 /*-
 311 Seems to cause problems using Exceed
 312 with PseudoColor
 313 X Error of failed request:  BadGC (invalid GC parameter)
 314 with TrueColor
 315 X Error of failed request:  BadDrawable (invalid Pixmap or Window parameter)
 316   Major opcode of failed request:  62 (X_CopyArea)
 317  */
 318                         XCopyArea(display, window, window, gc, xi, yi,
 319                                   sp->blit_width, sp->blit_height,
 320                                   qx, qy);
 321                         switch (sp->mode) {
 322                                 case 0:
 323                                         /* wrap */
 324                                         wrap = sp->width - (2 * sp->blit_width);
 325                                         if (qx > wrap ) {
 326                                                 XCopyArea(display, window, window, gc, qx, qy,
 327                                                 sp->blit_width, sp->blit_height,
 328                                                           qx - wrap, qy);
 329                                         }
 330                                         if (qx < 2 * sp->blit_width) {
 331                                                 XCopyArea(display, window, window, gc, qx, qy,
 332                                                 sp->blit_width, sp->blit_height,
 333                                                           qx + wrap, qy);
 334                                         }
 335                                         wrap = sp->height - (2 * sp->blit_height);
 336                                         if (qy > wrap) {
 337                                                 XCopyArea(display, window, window, gc, qx, qy,
 338                                                 sp->blit_width, sp->blit_height,
 339                                                           qx, qy - wrap);
 340                                         }
 341                                         if (qy < 2 * sp->blit_height) {
 342                                                 XCopyArea(display, window, window, gc, qx, qy,
 343                                                 sp->blit_width, sp->blit_height,
 344                                                           qx, qy + wrap);
 345                                         }
 346                                         break;
 347                                 case 1:
 348                                 case 2:
 349                                         break;
 350                         }
 351                 }
 352         }
 353 }
 354
 355 ENTRYPOINT void
 356 release_slip (ModeInfo * mi)
 357 {
 358         if (slips != NULL) {
 359                 (void) free((void *) slips);
 360                 slips = (slipstruct *) NULL;
 361         }
 362 }
 363
 364 XSCREENSAVER_MODULE ("Slip", slip)
 365
 366 #endif /* MODE_slip */