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