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