+++ /dev/null
-/* -*- Mode: C; tab-width: 4 -*-
- * grav --- simulation of a planetary system.
- */
-#if !defined( lint ) && !defined( SABER )
-static const char sccsid[] = "@(#)grav.c 4.00 97/01/01 xlockmore";
-#endif
-
-/* Copyright (c) 1993 Greg Bowering <greg@smug.student.adelaide.edu.au>
- *
- * 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:
- * 10-May-97: jwz@jwz.org: turned into a standalone program.
- * 11-Jul-94: color version
- * 06-Oct-93: by Greg Bowering <greg@smug.student.adelaide.edu.au>
- */
-
-#ifdef STANDALONE
-# define PROGCLASS "Grav"
-# define HACK_INIT init_grav
-# define HACK_DRAW draw_grav
-# define grav_opts xlockmore_opts
-# define DEFAULTS "*count: 12 \n" \
- "*delay: 10000 \n" \
- "*ncolors: 64 \n"
-# define BRIGHT_COLORS
-# include "xlockmore.h" /* from the xscreensaver distribution */
-#else /* !STANDALONE */
-# include "xlock.h" /* from the xlockmore distribution */
-#endif /* !STANDALONE */
-
-#define GRAV -0.02 /* Gravitational constant */
-#define DIST 16.0
-#define COLLIDE 0.0001
-#define ALMOST 15.99
-#define HALF 0.5
-/* #define INTRINSIC_RADIUS 200.0 */
-#define INTRINSIC_RADIUS ((float) (gp->height/5))
-#define STARRADIUS (unsigned int)(gp->height/(2*DIST))
-#define AVG_RADIUS (INTRINSIC_RADIUS/DIST)
-#define RADIUS (unsigned int)(INTRINSIC_RADIUS/(POS(Z)+DIST))
-
-#define XR HALF*ALMOST
-#define YR HALF*ALMOST
-#define ZR HALF*ALMOST
-
-#define VR 0.04
-
-#define DIMENSIONS 3
-#define X 0
-#define Y 1
-#define Z 2
-
-#define DAMP 0.999999
-#define MaxA 0.1 /* Maximum acceleration (w/ damping) */
-
-#define POS(c) planet->P[c]
-#define VEL(c) planet->V[c]
-#define ACC(c) planet->A[c]
-
-#define Planet(x,y)\
- if ((x) >= 0 && (y) >= 0 && (x) <= gp->width && (y) <= gp->height) {\
- if (planet->ri < 2)\
- XDrawPoint(display, window, gc, (x), (y));\
- else\
- XFillArc(display, window, gc,\
- (x) - planet->ri / 2, (y) - planet->ri / 2, planet->ri, planet->ri,\
- 0, 23040);\
- }
-
-#define FLOATRAND(min,max) ((min)+(LRAND()/MAXRAND)*((max)-(min)))
-
-#define DEF_DECAY "False" /* Damping for decaying orbits */
-#define DEF_TRAIL "False" /* For trails (works good in mono only) */
-
-static Bool decay;
-static Bool trail;
-
-static XrmOptionDescRec opts[] =
-{
- {"-decay", ".grav.decay", XrmoptionNoArg, (caddr_t) "on"},
- {"+decay", ".grav.decay", XrmoptionNoArg, (caddr_t) "off"},
- {"-trail", ".grav.trail", XrmoptionNoArg, (caddr_t) "on"},
- {"+trail", ".grav.trail", XrmoptionNoArg, (caddr_t) "off"}
-};
-static argtype vars[] =
-{
- {(caddr_t *) & decay, "decay", "Decay", DEF_DECAY, t_Bool},
- {(caddr_t *) & trail, "trail", "Trail", DEF_TRAIL, t_Bool}
-};
-static OptionStruct desc[] =
-{
- {"-/+decay", "turn on/off decaying orbits"},
- {"-/+trail", "turn on/off trail dots"}
-};
-
-ModeSpecOpt grav_opts = { 4, opts, 2, vars, desc };
-
-typedef struct {
- double P[DIMENSIONS], V[DIMENSIONS], A[DIMENSIONS];
- int xi, yi, ri;
- unsigned long colors;
-} planetstruct;
-
-typedef struct {
- int width, height;
- int x, y, sr, nplanets;
- unsigned long starcolor;
- planetstruct *planets;
-} gravstruct;
-
-static gravstruct *gravs = NULL;
-
-static void
-init_planet(ModeInfo * mi, planetstruct * planet)
-{
- Display *display = MI_DISPLAY(mi);
- Window window = MI_WINDOW(mi);
- GC gc = MI_GC(mi);
- gravstruct *gp = &gravs[MI_SCREEN(mi)];
-
- if (MI_NPIXELS(mi) > 2)
- planet->colors = MI_PIXEL(mi, NRAND(MI_NPIXELS(mi)));
- else
- planet->colors = MI_WIN_WHITE_PIXEL(mi);
- /* Initialize positions */
- POS(X) = FLOATRAND(-XR, XR);
- POS(Y) = FLOATRAND(-YR, YR);
- POS(Z) = FLOATRAND(-ZR, ZR);
-
- if (POS(Z) > -ALMOST) {
- planet->xi = (int)
- ((double) gp->width * (HALF + POS(X) / (POS(Z) + DIST)));
- planet->yi = (int)
- ((double) gp->height * (HALF + POS(Y) / (POS(Z) + DIST)));
- } else
- planet->xi = planet->yi = -1;
- planet->ri = RADIUS;
-
- /* Initialize velocities */
- VEL(X) = FLOATRAND(-VR, VR);
- VEL(Y) = FLOATRAND(-VR, VR);
- VEL(Z) = FLOATRAND(-VR, VR);
-
- /* Draw planets */
- Planet(planet->xi, planet->yi);
-}
-
-static void
-draw_planet(ModeInfo * mi, planetstruct * planet)
-{
- Display *display = MI_DISPLAY(mi);
- Window window = MI_WINDOW(mi);
- GC gc = MI_GC(mi);
- gravstruct *gp = &gravs[MI_SCREEN(mi)];
- double D; /* A distance variable to work with */
- register unsigned char cmpt;
-
- D = POS(X) * POS(X) + POS(Y) * POS(Y) + POS(Z) * POS(Z);
- if (D < COLLIDE)
- D = COLLIDE;
- D = sqrt(D);
- D = D * D * D;
- for (cmpt = X; cmpt < DIMENSIONS; cmpt++) {
- ACC(cmpt) = POS(cmpt) * GRAV / D;
- if (decay) {
- if (ACC(cmpt) > MaxA)
- ACC(cmpt) = MaxA;
- else if (ACC(cmpt) < -MaxA)
- ACC(cmpt) = -MaxA;
- VEL(cmpt) = VEL(cmpt) + ACC(cmpt);
- VEL(cmpt) *= DAMP;
- } else {
- /* update velocity */
- VEL(cmpt) = VEL(cmpt) + ACC(cmpt);
- }
- /* update position */
- POS(cmpt) = POS(cmpt) + VEL(cmpt);
- }
-
- gp->x = planet->xi;
- gp->y = planet->yi;
-
- if (POS(Z) > -ALMOST) {
- planet->xi = (int)
- ((double) gp->width * (HALF + POS(X) / (POS(Z) + DIST)));
- planet->yi = (int)
- ((double) gp->height * (HALF + POS(Y) / (POS(Z) + DIST)));
- } else
- planet->xi = planet->yi = -1;
-
- /* Mask */
- XSetForeground(display, gc, MI_WIN_BLACK_PIXEL(mi));
- Planet(gp->x, gp->y);
- if (trail) {
- XSetForeground(display, gc, planet->colors);
- XDrawPoint(display, MI_WINDOW(mi), gc, gp->x, gp->y);
- }
- /* Move */
- gp->x = planet->xi;
- gp->y = planet->yi;
- planet->ri = RADIUS;
-
- /* Redraw */
- XSetForeground(display, gc, planet->colors);
- Planet(gp->x, gp->y);
-}
-
-void
-init_grav(ModeInfo * mi)
-{
- Display *display = MI_DISPLAY(mi);
- GC gc = MI_GC(mi);
- gravstruct *gp;
- unsigned char ball;
-
- if (gravs == NULL) {
- if ((gravs = (gravstruct *) calloc(MI_NUM_SCREENS(mi),
- sizeof (gravstruct))) == NULL)
- return;
- }
- gp = &gravs[MI_SCREEN(mi)];
-
- gp->width = MI_WIN_WIDTH(mi);
- gp->height = MI_WIN_HEIGHT(mi);
-
- gp->sr = STARRADIUS;
-
- gp->nplanets = MI_BATCHCOUNT(mi);
- if (gp->nplanets < 0) {
- if (gp->planets) {
- (void) free((void *) gp->planets);
- gp->planets = NULL;
- }
- gp->nplanets = NRAND(-gp->nplanets) + 1; /* Add 1 so its not too boring */
- }
- if (!gp->planets)
- gp->planets = (planetstruct *) calloc(gp->nplanets, sizeof (planetstruct));
-
- XClearWindow(display, MI_WINDOW(mi));
-
- if (MI_NPIXELS(mi) > 2)
- gp->starcolor = MI_PIXEL(mi, NRAND(MI_NPIXELS(mi)));
- else
- gp->starcolor = MI_WIN_WHITE_PIXEL(mi);
- for (ball = 0; ball < (unsigned char) gp->nplanets; ball++)
- init_planet(mi, &gp->planets[ball]);
-
- /* Draw centrepoint */
- XDrawArc(display, MI_WINDOW(mi), gc,
- gp->width / 2 - gp->sr / 2, gp->height / 2 - gp->sr / 2, gp->sr, gp->sr,
- 0, 23040);
-}
-
-void
-draw_grav(ModeInfo * mi)
-{
- Display *display = MI_DISPLAY(mi);
- Window window = MI_WINDOW(mi);
- GC gc = MI_GC(mi);
- gravstruct *gp = &gravs[MI_SCREEN(mi)];
- register unsigned char ball;
-
- /* Mask centrepoint */
- XSetForeground(display, gc, MI_WIN_BLACK_PIXEL(mi));
- XDrawArc(display, window, gc,
- gp->width / 2 - gp->sr / 2, gp->height / 2 - gp->sr / 2, gp->sr, gp->sr,
- 0, 23040);
-
- /* Resize centrepoint */
- switch (NRAND(4)) {
- case 0:
- if (gp->sr < (int) STARRADIUS)
- gp->sr++;
- break;
- case 1:
- if (gp->sr > 2)
- gp->sr--;
- }
-
- /* Draw centrepoint */
- XSetForeground(display, gc, gp->starcolor);
- XDrawArc(display, window, gc,
- gp->width / 2 - gp->sr / 2, gp->height / 2 - gp->sr / 2, gp->sr, gp->sr,
- 0, 23040);
-
- for (ball = 0; ball < (unsigned char) gp->nplanets; ball++)
- draw_planet(mi, &gp->planets[ball]);
-}
-
-void
-release_grav(ModeInfo * mi)
-{
- if (gravs != NULL) {
- int screen;
-
- for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++) {
- gravstruct *gp = &gravs[screen];
-
- if (gp->planets)
- (void) free((void *) gp->planets);
- }
- (void) free((void *) gravs);
- gravs = NULL;
- }
-}
-
-void
-refresh_grav(ModeInfo * mi)
-{
- /* Do nothing, it will refresh by itself */
-}
projects / xscreensaver / blobdiff