1 /* ripples, Copyright (c) 1999 Ian McConnell <ian@emit.demon.co.uk>
3 * Permission to use, copy, modify, distribute, and sell this software and its
4 * documentation for any purpose is hereby granted without fee, provided that
5 * the above copyright notice appear in all copies and that both that
6 * copyright notice and this permission notice appear in supporting
7 * documentation. No representations are made about the suitability of this
8 * software for any purpose. It is provided "as is" without express or
13 * "Water" ripples that can cross and interfere with each other.
15 * I can't remember where I got this idea from, but it's been around for a
16 * while in various demos. Some inspiration from
17 * water.txt by Tom Hammersley,tomh@globalnet.co.uk
20 * -delay usleep every iteration
21 * -rate Add one drop every "rate" iterations
22 * -box Add big square splash every "box" iters (not very good)
23 * -water Ripples on a grabbed background image
24 * -foreground Interpolate ripples between these two colors
26 * -oily Psychedelic colours like man
27 * -stir Add a regular pattern of drops
28 * -fluidity Between 0 and 16. 16 = big drops
29 * -light Hack to add lighting effect
31 * Code mainly hacked from xflame and decayscreen.
35 * 13 Oct 1999: Initial hack
36 * 30 Oct 1999: Speeded up graphics with dirty buffer. Returned to using
37 * putpixel for greater portability
38 * Added a variety of methods for splashing screen.
39 * 31 Oct 1999: Added in lighting hack
40 * 13 Nov 1999: Speed up tweaks
41 * Adjust "light" for different bits per colour (-water only)
46 #include "screenhack.h"
48 typedef enum {ripple_drop, ripple_blob, ripple_box, ripple_stir} ripple_mode;
50 #ifdef HAVE_XSHM_EXTENSION
52 #endif /* HAVE_XSHM_EXTENSION */
62 XImage *orig_map, *buffer_map;
68 int width, height; /* ripple size */
69 int bigwidth, bigheight; /* screen size */
72 short *bufferA, *bufferB, *temp;
75 double cos_tab[TABLE];
79 unsigned long rmask; /* This builds on the warp effect by adding */
80 unsigned long gmask; /* in a lighting effect: brighten pixels by an */
81 unsigned long bmask; /* amount corresponding to the vertical gradient */
92 int iterations, delay, rate, box, oily, stir, fluidity;
94 void (*draw_transparent) (struct state *st, short *src);
96 async_load_state *img_loader;
98 #ifdef HAVE_XSHM_EXTENSION
100 XShmSegmentInfo shm_info;
101 #endif /* HAVE_XSHM_EXTENSION */
105 /* Distribution of drops: many little ones and a few big ones. */
106 static const double drop_dist[] =
107 {0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.2, 0.6};
110 /* How hard to hit the water */
113 #define MIN(x, y) ((x) < (y) ? (x) : (y))
115 #define MAX(x, y) ((x) > (y) ? (x) : (y))
117 #define DIRTY 3 /* dirty >= 2, 1 = restore original pixel, 0 = leave alone */
119 /* From fortune(6) */
120 /* -- really weird C code to count the number of bits in a word */
121 #define BITCOUNT(x) (((BX_(x)+(BX_(x)>>4)) & 0x0F0F0F0F) % 255)
122 #define BX_(x) ((x) - (((x)>>1)&0x77777777) \
123 - (((x)>>2)&0x33333333) \
124 - (((x)>>3)&0x11111111))
127 static unsigned long grayscale(struct state *st, unsigned long color);
129 /* ------------------------------------------- */
133 map_color(struct state *st, int grey)
136 grey = st->ncolors * abs(grey) / (SPLASH/4);
137 if (grey > st->ncolors)
141 return st->ctab[grey];
146 draw_ripple(struct state *st, short *src)
149 char *dirty = st->dirty_buffer;
151 for (down = 0; down < st->height - 1; down++, src += 1, dirty += 1)
152 for (across = 0; across < st->width - 1; across++, src++, dirty++) {
155 v2 = (int)*(src + 1);
156 v3 = (int)*(src + st->width);
157 v4 = (int)*(src + st->width + 1);
158 if ((v1 == 0 && v2 == 0 && v3 == 0 && v4 == 0)) {
167 dx = ((v3 - v1) + (v4 - v2)) << st->light; /* light from top */
170 XPutPixel(st->buffer_map,(across<<1), (down<<1), map_color(st, dx + v1));
171 XPutPixel(st->buffer_map,(across<<1)+1,(down<<1), map_color(st, dx + ((v1 + v2) >> 1)));
172 XPutPixel(st->buffer_map,(across<<1), (down<<1)+1,map_color(st, dx + ((v1 + v3) >> 1)));
173 XPutPixel(st->buffer_map,(across<<1)+1,(down<<1)+1,map_color(st, dx + ((v1 + v4) >> 1)));
179 /* ------------------------------------------- */
182 /* Uses the horizontal gradient as an offset to create a warp effect */
184 draw_transparent_vanilla(struct state *st, short *src)
186 int across, down, pixel;
187 char *dirty = st->dirty_buffer;
190 for (down = 0; down < st->height - 2; down++, pixel += 2)
191 for (across = 0; across < st->width-2; across++, pixel++) {
192 int gradx, grady, gradx1, grady1;
193 int x0, x1, x2, y1, y2;
198 y1 = src[pixel + st->width];
199 y2 = src[pixel + 2*st->width];
205 gradx1 = 1 + (gradx + gradx1) / 2;
206 grady1 = 1 + (grady + grady1) / 2;
208 if ((2*across+MIN(gradx,gradx1) < 0) ||
209 (2*across+MAX(gradx,gradx1) >= st->bigwidth)) {
213 if ((2*down+MIN(grady,grady1) < 0) ||
214 (2*down+MAX(grady,grady1) >= st->bigheight)) {
219 if ((gradx == 0 && gradx1 == 1 && grady == 0 && grady1 == 1)) {
220 if (dirty[pixel] > 0)
223 dirty[pixel] = DIRTY;
225 if (dirty[pixel] > 0) {
226 XPutPixel(st->buffer_map, (across<<1), (down<<1),
227 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady)));
228 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1),
229 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady)));
230 XPutPixel(st->buffer_map, (across<<1), (down<<1)+1,
231 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady1)));
232 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1)+1,
233 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady1)));
239 /* ------------------------------------------- */
243 set_mask(unsigned long color, unsigned long *mask, int *shift)
246 while (color != 0 && (color & 1) == 0) {
255 cadd(unsigned long color, int dx, unsigned long mask, int shift)
262 else if (x > (int)mask) x = mask;
264 return color << shift;
269 bright(struct state *st, int dx, unsigned long color)
271 return (cadd(color, dx, st->rmask, st->rshift) |
272 cadd(color, dx, st->gmask, st->gshift) |
273 cadd(color, dx, st->bmask, st->bshift));
278 grayscale(struct state *st, unsigned long color)
288 if (!st->grayscale_p)
290 if (!st->transparent)
292 if ((st->rmask == 0) || (st->gmask == 0) || (st->bmask == 0))
295 red = ((color >> st->rshift) & st->rmask);
296 green = ((color >> st->gshift) & st->gmask);
297 blue = ((color >> st->bshift) & st->bmask);
298 total = red * st->gmask * st->bmask + green * st->rmask * st->bmask + blue * st->rmask * st->gmask;
300 gray_r = total / (3 * st->gmask * st->bmask);
303 if (gray_r > st->rmask)
306 gray_g = total / (3 * st->rmask * st->bmask);
309 if (gray_g > st->gmask)
312 gray_b = total / (3 * st->rmask * st->gmask);
315 if (gray_b > st->bmask)
318 return ((unsigned long)
319 ((gray_r << st->rshift) | (gray_g << st->gshift) | (gray_b << st->bshift)));
324 draw_transparent_light(struct state *st, short *src)
326 int across, down, pixel;
327 char *dirty = st->dirty_buffer;
330 for (down = 0; down < st->height - 2; down++, pixel += 2)
331 for (across = 0; across < st->width-2; across++, pixel++) {
332 int gradx, grady, gradx1, grady1;
333 int x0, x1, x2, y1, y2;
338 y1 = src[pixel + st->width];
339 y2 = src[pixel + 2*st->width];
345 gradx1 = 1 + (gradx + gradx1) / 2;
346 grady1 = 1 + (grady + grady1) / 2;
348 if ((2*across+MIN(gradx,gradx1) < 0) ||
349 (2*across+MAX(gradx,gradx1) >= st->bigwidth)) {
353 if ((2*down+MIN(grady,grady1) < 0) ||
354 (2*down+MAX(grady,grady1) >= st->bigheight)) {
359 if ((gradx == 0 && gradx1 == 1 && grady == 0 && grady1 == 1)) {
360 if (dirty[pixel] > 0)
363 dirty[pixel] = DIRTY;
365 if (dirty[pixel] > 0) {
369 if (4-st->light >= 0)
370 dx = (grady + (src[pixel+st->width+1]-x1)) >> (4-st->light);
372 dx = (grady + (src[pixel+st->width+1]-x1)) << (st->light-4);
375 XPutPixel(st->buffer_map, (across<<1), (down<<1),
376 bright(st, dx, grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady))));
377 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1),
378 bright(st, dx, grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady))));
379 XPutPixel(st->buffer_map, (across<<1), (down<<1)+1,
380 bright(st, dx, grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady1))));
381 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1)+1,
382 bright(st, dx, grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady1))));
384 /* Could use XCopyArea, but XPutPixel is faster */
385 XPutPixel(st->buffer_map, (across<<1), (down<<1),
386 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady)));
387 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1),
388 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady)));
389 XPutPixel(st->buffer_map, (across<<1), (down<<1)+1,
390 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx, (down<<1) + grady1)));
391 XPutPixel(st->buffer_map, (across<<1)+1,(down<<1)+1,
392 grayscale(st, XGetPixel(st->orig_map, (across<<1) + gradx1,(down<<1) + grady1)));
399 /* ------------------------------------------- */
403 /* Doesn't go any faster and doesn't work at all colour depths */
405 draw_transparent16l(short *src)
407 int across, down, bigpix, pixel;
408 char *dirty = st->dirty_buffer;
409 unsigned short *buffer, *orig;
411 buffer = (unsigned short *) st->buffer_map->data;
412 orig = (unsigned short *) st->orig_map->data;
414 for (pixel = bigpix = down = 0;
415 down < st->height - 2;
416 down++, pixel += 2, bigpix += st->bigwidth+4)
417 for (across = 0; across < st->width-2; across++, pixel++, bigpix+=2) {
418 int gradx, grady, gradx1, grady1;
419 int x0, x1, x2, y1, y2;
424 y1 = src[pixel + st->width];
425 y2 = src[pixel + 2*st->width];
431 gradx1 = 1 + (gradx + gradx1) / 2;
432 grady1 = 1 + (grady + grady1) / 2;
434 if ((2*across+MIN(gradx,gradx1) < 0) ||
435 (2*across+MAX(gradx,gradx1) >= st->bigwidth)) {
439 if ((2*down+MIN(grady,grady1) < 0) ||
440 (2*down+MAX(grady,grady1) >= st->bigheight)) {
445 if ((gradx == 0 && gradx1 == 1 && grady == 0 && grady1 == 1)) {
446 if (dirty[pixel] > 0)
449 dirty[pixel] = DIRTY;
451 if (dirty[pixel] > 0) {
452 unsigned short *dest = buffer + bigpix;
453 unsigned short *image = orig + bigpix;
457 if (4-st->light >= 0)
458 dx = (grady + (src[pixel+st->width+1]-x1)) >> (4-st->light);
460 dx = (grady + (src[pixel+st->width+1]-x1)) << (st->light-4);
462 grady *= st->bigwidth;
463 grady1*= st->bigwidth;
466 *dest++ = dobright(dx, *(image + gradx + grady));
467 *dest = dobright(dx, *(image + gradx1 + grady));
468 dest += st->bigwidth - 1;
469 *dest++ = dobright(dx, *(image + gradx + grady1));
470 *dest = dobright(dx, *(image + gradx1 + grady1));
472 *dest++ = *(image + gradx + grady);
473 *dest = *(image + gradx1 + grady);
474 dest += st->bigwidth - 1;
475 *dest++ = *(image + gradx + grady1);
476 *dest = *(image + gradx1 + grady1);
484 /* ------------------------------------------- */
488 setup_X(struct state *st)
490 XWindowAttributes xgwa;
493 XGetWindowAttributes(st->dpy, st->window, &xgwa);
495 st->colormap = xgwa.colormap;
496 st->bigwidth = xgwa.width;
497 st->bigheight = xgwa.height;
498 st->visual = xgwa.visual;
501 /* This causes buffer_map to be 1 pixel taller and wider than orig_map,
502 which can cause the two XImages to have different bytes-per-line,
503 which causes stair-stepping. So this better not be necessary...
506 #if 0 /* I'm not entirely sure if I need this */
507 if (st->bigwidth % 2)
509 if (st->bigheight % 2)
514 st->width = st->bigwidth / 2;
515 st->height = st->bigheight / 2;
517 if (st->transparent) {
521 gcv.function = GXcopy;
522 gcv.subwindow_mode = IncludeInferiors;
524 gcflags = GCFunction;
525 if (use_subwindow_mode_p(xgwa.screen, st->window)) /* see grabscreen.c */
526 gcflags |= GCSubwindowMode;
528 st->gc = XCreateGC(st->dpy, st->window, gcflags, &gcv);
530 st->img_loader = load_image_async_simple (0, xgwa.screen, st->window,
535 st->gc = XCreateGC(st->dpy, st->window, 0, &gcv);
540 fprintf(stderr, "XCreateGC failed\n");
546 #ifdef HAVE_XSHM_EXTENSION
548 st->buffer_map = create_xshm_image(st->dpy, xgwa.visual, depth,
549 ZPixmap, 0, &st->shm_info, st->bigwidth, st->bigheight);
550 if (!st->buffer_map) {
552 fprintf(stderr, "create_xshm_image failed\n");
555 #endif /* HAVE_XSHM_EXTENSION */
557 if (!st->buffer_map) {
558 st->buffer_map = XCreateImage(st->dpy, xgwa.visual,
559 depth, ZPixmap, 0, 0,
560 st->bigwidth, st->bigheight, 8, 0);
561 st->buffer_map->data = (char *)
562 calloc(st->buffer_map->height, st->buffer_map->bytes_per_line);
568 DisplayImage(struct state *st)
570 #ifdef HAVE_XSHM_EXTENSION
572 XShmPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, 0, 0,
573 st->bigwidth, st->bigheight, False);
575 #endif /* HAVE_XSHM_EXTENSION */
576 XPutImage(st->dpy, st->window, st->gc, st->buffer_map, 0, 0, 0, 0,
577 st->bigwidth, st->bigheight);
581 /* ------------------------------------------- */
585 cinterp(double a, int bg, int fg)
588 result = (int)((1-a) * bg + a * fg + 0.5);
589 if (result < 0) result = 0;
590 if (result > 255) result = 255;
595 /* Interpolate the ripple colours between the background colour and
598 init_linear_colors(struct state *st)
600 int i, j, red, green, blue, bred, bgreen, bblue;
603 if (st->ncolors < 2 || mono_p)
605 if (st->ncolors <= 2)
608 /* Make it possible to set the color of the ripples,
609 Based on work by Raymond Medeiros <ray@stommel.marine.usf.edu> and jwz.
611 fg.pixel = get_pixel_resource(st->dpy, st->colormap, "foreground", "Foreground");
612 XQueryColor(st->dpy, st->colormap, &fg);
614 green = (fg.green >> 8);
615 blue = (fg.blue >> 8);
617 bg.pixel = get_pixel_resource(st->dpy, st->colormap, "background", "Background");
618 XQueryColor(st->dpy, st->colormap, &bg);
619 bred = (bg.red >> 8);
620 bgreen = (bg.green >> 8);
621 bblue = (bg.blue >> 8);
624 for (i = 0; i < st->ncolors+1; i++) {
626 double a = (double)i / st->ncolors;
627 int r = cinterp(a, bred, red);
628 int g = cinterp(a, bgreen, green);
629 int b = cinterp(a, bblue, blue);
631 xcl.red = (unsigned short) ((r << 8) | r);
632 xcl.green = (unsigned short) ((g << 8) | g);
633 xcl.blue = (unsigned short) ((b << 8) | b);
634 xcl.flags = DoRed | DoGreen | DoBlue;
636 XAllocColor(st->dpy, st->colormap, &xcl);
638 st->ctab[j++] = (int) xcl.pixel;
644 init_oily_colors(struct state *st)
646 XColor *colors = NULL;
648 if (st->ncolors < 2 || mono_p)
650 if (st->ncolors <= 2)
655 colors = (XColor *)malloc(sizeof(*colors) * (st->ncolors+1));
656 make_smooth_colormap(st->dpy, st->visual, st->colormap, colors, &st->ncolors,
658 False, /* not writable */
659 True); /* verbose (complain about failure) */
660 if (st->ncolors <= 2) {
669 for (i = 0; i < st->ncolors+1; i++) {
670 XAllocColor(st->dpy, st->colormap, colors+i);
671 st->ctab[j++] = (int) colors[i].pixel;
676 st->ctab[1] = get_pixel_resource(st->dpy, st->colormap, "foreground", "Foreground");
677 st->ctab[0] = get_pixel_resource(st->dpy, st->colormap, "background", "Background");
682 /* ------------------------------------------- */
686 init_cos_tab(struct state *st)
689 for (i = 0; i < TABLE; i++)
690 st->cos_tab[i] = cos(i * M_PI/2 / TABLE);
694 /* Shape of drop to add */
696 sinc(struct state *st, double x)
701 i = (int)(x * TABLE + 0.5);
702 if (i >= TABLE) i = (TABLE-1) - (i-(TABLE-1));
703 return st->cos_tab[i];
705 return cos(x * M_PI/2);
716 add_circle_drop(struct state *st, int x, int y, int radius, int dheight)
719 short *buf = (random()&1) ? st->bufferA : st->bufferB;
721 i = y * st->width + x;
722 r2 = radius * radius;
724 for (cy = -radius; cy <= radius; cy++)
725 for (cx = -radius; cx <= radius; cx++) {
726 int r = cx*cx + cy*cy;
728 buf[i + cx + cy*st->width] =
729 (short)(dheight * sinc(st, sqrt(r)/radius));
736 add_drop(struct state *st, ripple_mode mode, int drop)
738 int newx, newy, dheight;
739 int radius = MIN(st->width, st->height) / 50;
740 /* Don't put drops too near the edge of the screen or they get stuck */
748 dheight = 1 + (random() % drop);
749 newx = border + (random() % (st->width - 2*border));
750 newy = border + (random() % (st->height - 2*border));
751 x = newy * st->width + newx;
752 st->bufferA[x + 1] = st->bufferA[x] = st->bufferA[x + st->width] = st->bufferA[x + st->width + 1] =
753 st->bufferB[x + 1] = st->bufferB[x] = st->bufferB[x + st->width] = st->bufferB[x + st->width + 1] =
760 power = drop_dist[random() % (sizeof(drop_dist)/sizeof(drop_dist[0]))]; /* clumsy */
761 dheight = (int)(drop * (power + 0.01));
762 newx = radius + border + (random() % (int)(st->width - 2*border - 2*radius*power));
763 newy = radius + border + (random() % (int)(st->height - 2*border - 2*radius*power));
764 add_circle_drop(st, newx, newy, radius, dheight);
767 /* Adding too many boxes too quickly (-box 1) doesn't give the waves time
768 to disperse and the waves build up (and overflow) */
772 short *buf = (random()&1) ? st->bufferA : st->bufferB;
774 radius = (1 + (random() % 5)) * (1 + (random() % 5));
775 dheight = drop / 128;
776 if (random() & 1) dheight = -dheight;
777 newx = radius + border + (random() % (st->width - 2*border - 2*radius));
778 newy = radius + border + (random() % (st->height - 2*border - 2*radius));
779 x = newy * st->width + newx;
780 for (cy = -radius; cy <= radius; cy++)
781 for (cx = -radius; cx <= radius; cx++)
782 buf[x + cx + cy*st->width] = (short)(dheight);
787 newx = border + (int)((st->width-2*border) * (1+cos(3*st->stir_ang)) / 2);
788 newy = border + (int)((st->height-2*border) * (1+sin(2*st->stir_ang)) / 2);
789 add_circle_drop(st, newx, newy, radius, drop / 10);
790 st->stir_ang += 0.02;
791 if (st->stir_ang > 12*M_PI) st->stir_ang = 0;
799 init_ripples(struct state *st, int ndrops, int splash)
803 st->bufferA = (short *)calloc(st->width * st->height, sizeof(*st->bufferA));
804 st->bufferB = (short *)calloc(st->width * st->height, sizeof(*st->bufferB));
805 st->temp = (short *)calloc(st->width * st->height, sizeof(*st->temp));
807 st->dirty_buffer = (char *)calloc(st->width * st->height, sizeof(*st->dirty_buffer));
809 for (i = 0; i < ndrops; i++)
810 add_drop(st, ripple_blob, splash);
812 if (st->transparent) {
816 for (down = 0; down < st->bigheight; down++)
817 for (across = 0; across < st->bigwidth; across++)
818 XPutPixel(st->buffer_map, across, down,
819 grayscale(st, XGetPixel(st->orig_map, across, down)));
823 /* There's got to be a better way of doing this XCopyArea? */
824 memcpy(st->buffer_map->data, st->orig_map->data,
825 st->bigheight * st->buffer_map->bytes_per_line);
828 int across, down, color;
830 color = map_color(st, 0); /* background colour */
831 for (down = 0; down < st->bigheight; down++)
832 for (across = 0; across < st->bigwidth; across++)
833 XPutPixel(st->buffer_map,across, down, color);
841 Explanation from hq_water.zip (Arturo R Montesinos (ARM) arami@fi.upm.es)
843 Differential equation is: u = a ( u + u )
846 Where a = tension * gravity / surface_density.
848 Approximating second derivatives by central differences:
850 [ u(t+1)-2u(t)+u(t-1) ] / dt = a [ u(x+1)+u(x-1)+u(y+1)+u(y-1)-4u ] / h
852 where dt = time step squared, h = dx*dy = mesh resolution squared.
854 From where u(t+1) may be calculated as:
857 u(t+1) = a -- | 1 0 1 |u - u(t-1) + (2-4a --)u
860 When a*dt/h = 1/2 last term vanishes, giving:
863 u(t+1) = - | 1 0 1 |u - u(t-1)
866 (note that u(t-1,x,y) is only used to calculate u(t+1,x,y) so
867 we can use the same array for both t-1 and t+1, needing only
868 two arrays, U[0] and U[1])
870 Dampening is simulated by subtracting 1/2^n of result.
871 n=4 gives best-looking result
872 n<4 (eg 2 or 3) thicker consistency, waves die out immediately
873 n>4 (eg 8 or 12) more fluid, waves die out slowly
877 ripple(struct state *st)
879 int across, down, pixel;
882 if (st->draw_toggle == 0) {
892 switch (st->draw_count) {
894 pixel = 1 * st->width + 1;
895 for (down = 1; down < st->height - 1; down++, pixel += 2 * 1)
896 for (across = 1; across < st->width - 1; across++, pixel++) {
898 (((src[pixel - 1] + src[pixel + 1] +
899 src[pixel - st->width] + src[pixel + st->width]) / 2)) - dest[pixel];
902 /* Smooth the output */
903 pixel = 1 * st->width + 1;
904 for (down = 1; down < st->height - 1; down++, pixel += 2 * 1)
905 for (across = 1; across < st->width - 1; across++, pixel++) {
906 if (st->temp[pixel] != 0) { /* Close enough for government work */
908 (st->temp[pixel - 1] + st->temp[pixel + 1] +
909 st->temp[pixel - st->width] + st->temp[pixel + st->width] +
910 st->temp[pixel - st->width - 1] + st->temp[pixel - st->width + 1] +
911 st->temp[pixel + st->width - 1] + st->temp[pixel + st->width + 1] +
912 st->temp[pixel]) / 9;
913 dest[pixel] = damp - (damp >> st->fluidity);
919 pixel = 1 * st->width + 1;
920 for (down = 1; down < st->height - 1; down++, pixel += 2 * 1)
921 for (across = 1; across < st->width - 1; across++, pixel++) {
923 (((src[pixel - 1] + src[pixel + 1] +
924 src[pixel - st->width] + src[pixel + st->width]) / 2)) - dest[pixel];
925 dest[pixel] = damp - (damp >> st->fluidity);
929 if (++st->draw_count > 3) st->draw_count = 0;
932 st->draw_transparent(st, dest);
934 draw_ripple(st, dest);
938 /* ------------------------------------------- */
941 ripples_init (Display *disp, Window win)
943 struct state *st = (struct state *) calloc (1, sizeof(*st));
947 st->delay = get_integer_resource(disp, "delay", "Integer");
948 st->rate = get_integer_resource(disp, "rate", "Integer");
949 st->box = get_integer_resource(disp, "box", "Integer");
950 st->oily = get_boolean_resource(disp, "oily", "Boolean");
951 st->stir = get_boolean_resource(disp, "stir", "Boolean");
952 st->fluidity = get_integer_resource(disp, "fluidity", "Integer");
953 st->transparent = get_boolean_resource(disp, "water", "Boolean");
954 st->grayscale_p = get_boolean_resource(disp, "grayscale", "Boolean");
955 #ifdef HAVE_XSHM_EXTENSION
956 st->use_shm = get_boolean_resource(disp, "useSHM", "Boolean");
957 #endif /* HAVE_XSHM_EXTENSION */
958 st->light = get_integer_resource(disp, "light", "Integer");
960 if (st->fluidity <= 1) st->fluidity = 1;
961 if (st->fluidity > 16) st->fluidity = 16; /* 16 = sizeof(short) */
962 if (st->light < 0) st->light = 0;
967 st->ncolors = get_integer_resource (disp, "colors", "Colors");
968 if (0 == st->ncolors) /* English spelling? */
969 st->ncolors = get_integer_resource (disp, "colours", "Colors");
971 if (st->ncolors > sizeof(st->ctab)/sizeof(*st->ctab))
972 st->ncolors = sizeof(st->ctab)/sizeof(*st->ctab);
975 init_oily_colors(st);
977 init_linear_colors(st);
979 if (st->transparent && st->light > 0) {
981 st->draw_transparent = draw_transparent_light;
982 set_mask(st->visual->red_mask, &st->rmask, &st->rshift);
983 set_mask(st->visual->green_mask, &st->gmask, &st->gshift);
984 set_mask(st->visual->blue_mask, &st->bmask, &st->bshift);
985 if (st->rmask == 0) st->draw_transparent = draw_transparent_vanilla;
987 /* Adjust the shift value "light" when we don't have 8 bits per colour */
988 maxbits = MIN(MIN(BITCOUNT(st->rmask), BITCOUNT(st->gmask)), BITCOUNT(st->bmask));
989 st->light -= 8-maxbits;
990 if (st->light < 0) st->light = 0;
994 set_mask(st->visual->red_mask, &st->rmask, &st->rshift);
995 set_mask(st->visual->green_mask, &st->gmask, &st->gshift);
996 set_mask(st->visual->blue_mask, &st->bmask, &st->bshift);
998 st->draw_transparent = draw_transparent_vanilla;
1001 if (!st->transparent)
1002 init_ripples(st, 0, -SPLASH); /* Start off without any drops */
1007 static unsigned long
1008 ripples_draw (Display *dpy, Window window, void *closure)
1010 struct state *st = (struct state *) closure;
1012 if (st->img_loader) /* still loading */
1014 st->img_loader = load_image_async_simple (st->img_loader, 0, 0, 0, 0, 0);
1015 if (! st->img_loader) { /* just finished */
1016 XWindowAttributes xgwa;
1017 XGetWindowAttributes(st->dpy, st->window, &xgwa);
1018 st->orig_map = XGetImage (st->dpy, st->window, 0, 0,
1019 xgwa.width, xgwa.height,
1021 init_ripples(st, 0, -SPLASH); /* Start off without any drops */
1026 if (st->rate > 0 && (st->iterations % st->rate) == 0)
1027 add_drop(st, ripple_blob, -SPLASH);
1029 add_drop(st, ripple_stir, -SPLASH);
1030 if (st->box > 0 && (random() % st->box) == 0)
1031 add_drop(st, ripple_box, -SPLASH);
1043 ripples_reshape (Display *dpy, Window window, void *closure,
1044 unsigned int w, unsigned int h)
1049 ripples_event (Display *dpy, Window window, void *closure, XEvent *event)
1055 ripples_free (Display *dpy, Window window, void *closure)
1057 struct state *st = (struct state *) closure;
1061 static const char *ripples_defaults[] =
1063 ".background: black",
1064 ".foreground: #FFAF5F",
1066 "*dontClearRoot: True",
1075 "*grayscale: False",
1076 #ifdef HAVE_XSHM_EXTENSION
1084 static XrmOptionDescRec ripples_options[] =
1086 { "-colors", ".colors", XrmoptionSepArg, 0},
1087 { "-colours", ".colors", XrmoptionSepArg, 0},
1088 {"-delay", ".delay", XrmoptionSepArg, 0},
1089 {"-rate", ".rate", XrmoptionSepArg, 0},
1090 {"-box", ".box", XrmoptionSepArg, 0},
1091 {"-water", ".water", XrmoptionNoArg, "True"},
1092 {"-oily", ".oily", XrmoptionNoArg, "True"},
1093 {"-stir", ".stir", XrmoptionNoArg, "True"},
1094 {"-fluidity", ".fluidity", XrmoptionSepArg, 0},
1095 {"-light", ".light", XrmoptionSepArg, 0},
1096 {"-grayscale", ".grayscale", XrmoptionNoArg, "True"},
1097 {"-shm", ".useSHM", XrmoptionNoArg, "True"},
1098 {"-no-shm", ".useSHM", XrmoptionNoArg, "False"},
1103 XSCREENSAVER_MODULE ("Ripples", ripples)