/* -*- Mode: C; tab-width: 4 -*- */
/* sphere --- a bunch of shaded spheres */
#if 0
static const char sccsid[] = "@(#)sphere.c 5.00 2000/11/01 xlockmore";
#endif
/*-
* Copyright (c) 1988 by Sun Microsystems
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appear in all copies and that
* both that copyright notice and this permission notice appear in
* supporting documentation.
*
* This file is provided AS IS with no warranties of any kind. The author
* shall have no liability with respect to the infringement of copyrights,
* trade secrets or any patents by this file or any part thereof. In no
* event will the author be liable for any lost revenue or profits or
* other special, indirect and consequential damages.
*
* Revision History:
* 01-Nov-2000: Allocation checks
* 30-May-1997: <jwz@jwz.org> made it go vertically as well as horizontally.
* 27-May-1997: <jwz@jwz.org> turned into a standalone program.
* 02-Sep-1993: xlock version David Bagley <bagleyd@tux.org>
* 1988: Revised to use SunView canvas instead of gfxsw Sun Microsystems
* 1982: Orignal Algorithm Tom Duff Lucasfilm Ltd.
*/
/*-
* original copyright
* **************************************************************************
* Copyright 1988 by Sun Microsystems, Inc. Mountain View, CA.
*
* All Rights Reserved
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted, provided
* that the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the names of Sun or MIT not be used in advertising
* or publicity pertaining to distribution of the software without specific
* prior written permission. Sun and M.I.T. make no representations about the
* suitability of this software for any purpose. It is provided "as is"
* without any express or implied warranty.
*
* SUN DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
* IN NO EVENT SHALL SUN BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
* ***************************************************************************
*/
#ifdef STANDALONE
# define MODE_sphere
#define DEFAULTS "*delay: 20000 \n" \
"*cycles: 20 \n" \
"*size: 0 \n" \
"*ncolors: 64 \n" \
"*fpsSolid: true \n" \
# define BRIGHT_COLORS
# define release_sphere 0
# define reshape_sphere 0
# define sphere_handle_event 0
# include "xlockmore.h" /* from the xscreensaver distribution */
#else /* !STANDALONE */
# include "xlock.h" /* from the xlockmore distribution */
#endif /* !STANDALONE */
#ifdef MODE_sphere
ENTRYPOINT ModeSpecOpt sphere_opts =
{0, (XrmOptionDescRec *) NULL, 0, (argtype *) NULL, (OptionStruct *) NULL};
#ifdef USE_MODULES
ModStruct sphere_description =
{"sphere", "init_sphere", "draw_sphere", (char *) NULL,
"refresh_sphere", "init_sphere", "free_sphere", &sphere_opts,
5000, 1, 20, 0, 64, 1.0, "",
"Shows a bunch of shaded spheres", 0, NULL};
#endif
/*-
* (NX, NY, NZ) is the light source vector -- length should be 100
*/
#define NX 48
#define NY (-36)
#define NZ 80
#define NR 100
#define SQRT(a) ((int)sqrt((double)(a)))
typedef struct {
int width, height;
int radius;
int x0; /* x center */
int y0; /* y center */
int color;
int x, y;
int dirx, diry;
int shadowx, shadowy;
int maxx, maxy;
XPoint *points;
} spherestruct;
static spherestruct *spheres = (spherestruct *) NULL;
ENTRYPOINT void
init_sphere(ModeInfo * mi)
{
spherestruct *sp;
MI_INIT (mi, spheres);
sp = &spheres[MI_SCREEN(mi)];
if (sp->points != NULL) {
(void) free((void *) sp->points);
sp->points = (XPoint *) NULL;
}
sp->width = MAX(MI_WIDTH(mi), 4);
sp->height = MAX(MI_HEIGHT(mi), 4);
if ((sp->points = (XPoint *) malloc(MIN(sp->width, sp->height) *
sizeof (XPoint))) == NULL) {
return;
}
MI_CLEARWINDOW(mi);
sp->dirx = 1;
sp->x = sp->radius;
sp->shadowx = (LRAND() & 1) ? 1 : -1;
sp->shadowy = (LRAND() & 1) ? 1 : -1;
}
ENTRYPOINT void
draw_sphere(ModeInfo * mi)
{
Display *display = MI_DISPLAY(mi);
GC gc = MI_GC(mi);
int sqrd, nd;
register int minx = 0, maxx = 0, miny = 0, maxy = 0, npts = 0;
spherestruct *sp;
if (spheres == NULL)
return;
sp = &spheres[MI_SCREEN(mi)];
if (sp->points == NULL)
return;
MI_IS_DRAWN(mi) = True;
if ((sp->dirx && ABS(sp->x) >= sp->radius) ||
(sp->diry && ABS(sp->y) >= sp->radius)) {
sp->radius = NRAND(MIN(sp->width / 2, sp->height / 2) - 1) + 1;
if (LRAND() & 1) {
sp->dirx = (int) (LRAND() & 1) * 2 - 1;
sp->diry = 0;
} else {
sp->dirx = 0;
sp->diry = (int) (LRAND() & 1) * 2 - 1;
}
sp->x0 = NRAND(sp->width);
sp->y0 = NRAND(sp->height);
sp->x = -sp->radius * sp->dirx;
sp->y = -sp->radius * sp->diry;
if (MI_NPIXELS(mi) > 2)
sp->color = NRAND(MI_NPIXELS(mi));
}
if (sp->dirx == 1) {
if (sp->x0 + sp->x < 0)
sp->x = -sp->x0;
} else if (sp->dirx == -1) {
if (sp->x0 + sp->x >= sp->width)
sp->x = sp->width - sp->x0 - 1;
}
if (sp->diry == 1) {
if (sp->y0 + sp->y < 0)
sp->y = -sp->y0;
} else if (sp->diry == -1) {
if (sp->y0 + sp->y >= sp->height)
sp->y = sp->height - sp->y0 - 1;
}
if (sp->dirx) {
sp->maxy = SQRT(sp->radius * sp->radius - sp->x * sp->x);
miny = -sp->maxy;
if (sp->y0 - sp->maxy < 0)
miny = -sp->y0;
maxy = sp->maxy;
}
if (sp->diry) {
sp->maxx = SQRT(sp->radius * sp->radius - sp->y * sp->y);
minx = -sp->maxx;
if (sp->x0 - sp->maxx < 0)
minx = -sp->x0;
maxx = sp->maxx;
}
if (sp->dirx) {
if (sp->y0 + sp->maxy >= sp->height)
maxy = sp->height - sp->y0;
}
if (sp->diry) {
if (sp->x0 + sp->maxx >= sp->width)
maxx = sp->width - sp->x0;
}
XSetForeground(display, gc, MI_BLACK_PIXEL(mi));
if (sp->dirx)
XDrawLine(display, MI_WINDOW(mi), gc,
sp->x0 + sp->x, sp->y0 + miny, sp->x0 + sp->x, sp->y0 + maxy);
if (sp->diry)
XDrawLine(display, MI_WINDOW(mi), gc,
sp->x0 + minx, sp->y0 + sp->y, sp->x0 + maxx, sp->y0 + sp->y);
if (MI_NPIXELS(mi) > 2)
XSetForeground(display, gc, MI_PIXEL(mi, sp->color));
else
XSetForeground(display, gc, MI_WHITE_PIXEL(mi));
if (sp->dirx) {
sqrd = sp->radius * sp->radius - sp->x * sp->x;
nd = NX * sp->shadowx * sp->x;
for (sp->y = miny; sp->y <= maxy; sp->y++)
if ((NRAND(sp->radius * NR)) <= nd + NY * sp->shadowy * sp->y +
NZ * SQRT(sqrd - sp->y * sp->y)) {
sp->points[npts].x = sp->x + sp->x0;
sp->points[npts].y = sp->y + sp->y0;
npts++;
}
}
if (sp->diry) {
sqrd = sp->radius * sp->radius - sp->y * sp->y;
nd = NY * sp->shadowy * sp->y;
for (sp->x = minx; sp->x <= maxx; sp->x++)
if ((NRAND(sp->radius * NR)) <= NX * sp->shadowx * sp->x + nd +
NZ * SQRT(sqrd - sp->x * sp->x)) {
sp->points[npts].x = sp->x + sp->x0;
sp->points[npts].y = sp->y + sp->y0;
npts++;
}
}
XDrawPoints(display, MI_WINDOW(mi), gc, sp->points, npts, CoordModeOrigin);
if (sp->dirx == 1) {
sp->x++;
if (sp->x0 + sp->x >= sp->width)
sp->x = sp->radius;
} else if (sp->dirx == -1) {
sp->x--;
if (sp->x0 + sp->x < 0)
sp->x = -sp->radius;
}
if (sp->diry == 1) {
sp->y++;
if (sp->y0 + sp->y >= sp->height)
sp->y = sp->radius;
} else if (sp->diry == -1) {
sp->y--;
if (sp->y0 + sp->y < 0)
sp->y = -sp->radius;
}
}
ENTRYPOINT void
free_sphere(ModeInfo * mi)
{
spherestruct *sp;
if (spheres == NULL)
return;
sp = &spheres[MI_SCREEN(mi)];
if (sp->points) {
(void) free((void *) sp->points);
/* sp->points = NULL; */
}
}
#ifndef STANDALONE
ENTRYPOINT void
refresh_sphere(ModeInfo * mi)
{
spherestruct *sp;
if (spheres == NULL)
return;
sp = &spheres[MI_SCREEN(mi)];
MI_CLEARWINDOW(mi);
sp->x = -sp->radius;
}
#endif
XSCREENSAVER_MODULE ("Sphere", sphere)
#endif /* MODE_sphere */
