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