static void do_twinkle(Display *dpy, Window window) {
Colormap cmap;
XWindowAttributes xgwa;
int got_color = 0;
XColor color[maxps];
XColor bgcolor;
int p,f,nt, sx,sy, resets,lastresets,cnt;
XClearWindow (dpy, window);
XGetWindowAttributes (dpy, window, &xgwa);
cmap = xgwa.colormap;
scrwid = xgwa.width;
scrhei = xgwa.height;
/* Setup colours */
hsv_to_rgb (0.0, 0.0, 0.0, &bgcolor.red, &bgcolor.green, &bgcolor.blue);
got_color = XAllocColor (dpy, cmap, &bgcolor);
for (p=0;p<ps;p++) {
if (!mono_p)
hsv_to_rgb (random()%360, .6+.4*myrnd(), .6+.4*myrnd(), &color[p].red, &color[p].green, &color[p].blue);
/* hsv_to_rgb (random()%360, 1.0, 1.0, &color[p].red, &color[p].green, &color[p].blue); for stronger colours! */
if ((!mono_p) && (got_color = XAllocColor (dpy, cmap, &color[p]))) {
} else {
if (p>0)
color[p]=color[0];
else
color[p].pixel=default_fg_pixel;
}
}
/* Set up parameter movements for the different forcefields */
name[1] = "Velocity";
op[1] = 1; damp[1] = .999; force[1] = .002;
name[2] = "Rotation";
op[2] = 0; damp[2] = .999; force[2] = .002;
name[3] = "Drip";
op[3] = 1; damp[3] = .999; force[3] = .005;
name[4] = "Dribble";
op[4] = 1; damp[4] = .999; force[4] = .005;
name[5] = "Slide";
op[5] = 0; damp[5] = .999; force[5] = .002;
name[6] = "Accelerate";
op[6] = 1.0; damp[6] = .999; force[6] = .005;
name[7] = "xDisplace";
op[7] = 0; damp[7] = .999; force[7] = .005;
name[8] = "yDisplace";
op[8] = 0; damp[8] = .999; force[8] = .005;
/* 0 and 9 are options for splitting displacements [no var] */
name[0] = "Split";
op[0] = 0; damp[0] = 0; force[0] = 0;
name[9] = "2d/3d split";
op[9] = 0; damp[9] = 0; force[9] = 0;
/* Initialise parameters to optimum, all off */
for (f=0;f<fs;f++) {
var[f]=op[f];
fon[f]=0;
}
/* Initialise stars */
for (p=0;p<ps;p++)
stars_newp(p);
/* tx[nt],ty[nt] remeber earlier screen plots (tails of stars)
which are deleted when nt comes round again */
nt=0;
resets=0;
while (1) {
/* Move current points */
lastresets=resets;
resets=0;
for (p=0;p<ps;p++) {
/* Erase old */
XSetForeground (dpy, draw_gc, bgcolor.pixel);
XDrawPoint(dpy,window,draw_gc,tx[nt],ty[nt]);
/* Move */
stars_move(p);
/* If moved off screen, create a new one */
if (cx[p]<-1.0 || cx[p]>+1.0 ||
cy[p]<-1.0 || cy[p]>+1.0 ||
fabs(cx[p])<.001 || fabs(cy[p])<.001) {
stars_newp(p);
resets++;
} else if (myrnd()>0.99) /* Reset at random */
stars_newp(p);
/* Draw point */
sx=stars_scrpos_x(p);
sy=stars_scrpos_y(p);
XSetForeground (dpy, draw_gc, color[p].pixel);
XDrawPoint(dpy,window,draw_gc,sx,sy);
/* Remember it for removal later */
tx[nt]=sx;
ty[nt]=sy;
nt=(nt+1)%(ps*ts);
}
/* Adjust force fields */
cnt=0;
for (f=0;f<fs;f++) {
if (meters) { /* Remove meter from display */
XSetForeground(dpy, draw_gc, bgcolor.pixel);
stars_draw_meter(dpy,window,draw_gc,f);
}
/* Adjust forcefield's parameter */
var[f]=stars_perturb(var[f],op[f],damp[f],force[f]);
if (myrnd()>0.998) /* Turn it on/off ? */
fon[f]=(myrnd()<0.0);
/* fon[f]=!fon[f]; */
if (meters) { /* Redraw the meter */
XSetForeground(dpy, draw_gc, color[f].pixel);
stars_draw_meter(dpy,window,draw_gc,f);
}
if (fon[f])
cnt++;
}
if (cnt==0) { /* Ensure at least one is on! */
f=random() % fs;
fon[f]=1;
}
if (meters) {
XSetForeground(dpy, draw_gc, bgcolor.pixel);
XDrawRectangle(dpy,window,draw_gc,0,0,lastresets*5,3);
XSetForeground(dpy, draw_gc, default_fg_pixel);
XDrawRectangle(dpy,window,draw_gc,0,0,resets*5,3);
}
/* if (resets*5>scrwid) {
Turn one off a field if too many points are flying off screen */
/* This was a problem when one of the force-fields was acting wrong,
but not really needed any more unless we need to debug new ones ...! */
/* for (f=0;f<fs;f++)
if (fon[f])
printf("%i",f);
printf("\n");
XSync (dpy, False);
screenhack_handle_events (dpy);
sleep(1);
do { // In fact this bit might go wrong if
f=random() % fs; // we have not ensured at least one is on (above)
} while (!fon[f]);
fon[f]=0;
} */
XSync (dpy, False);
screenhack_handle_events (dpy);
}
}
static unsigned long
whirlwindwarp_draw (Display *dpy, Window window, void *closure)
{
struct state *st = (struct state *) closure;
/* time_t lastframe = time((time_t) 0); */
if (!st->initted) {
st->initted = 1;
XClearWindow (st->dpy, st->window);
XGetWindowAttributes (st->dpy, st->window, &st->xgwa);
st->scrwid = st->xgwa.width;
st->scrhei = st->xgwa.height;
st->starsize=st->scrhei/480;
if (st->starsize<=0)
st->starsize=1;
/* Setup colours */
hsv_to_rgb (0.0, 0.0, 0.0, &st->bgcolor.red, &st->bgcolor.green, &st->bgcolor.blue);
st->got_color = XAllocColor (st->dpy, st->xgwa.colormap, &st->bgcolor);
st->colsavailable=0;
for (st->p=0;st->p<st->ps;st->p++) {
if (!mono_p)
hsv_to_rgb (random()%360, .6+.4*myrnd(), .6+.4*myrnd(), &st->color[st->p].red, &st->color[st->p].green, &st->color[st->p].blue);
/* hsv_to_rgb (random()%360, 1.0, 1.0, &color[p].red, &color[p].green, &color[p].blue); for stronger colours! */
if ((!mono_p) && (st->got_color = XAllocColor (st->dpy, st->xgwa.colormap, &st->color[st->p]))) {
st->colsavailable=st->p;
} else {
if (st->colsavailable>0) /* assign colours from those already allocated */
st->color[st->p]=st->color[ st->p % st->colsavailable ];
else
st->color[st->p].pixel=st->default_fg_pixel;
}
}
/* Set up central (optimal) points for each different forcefield */
st->op[1] = 1; st->name[1] = "Warp";
st->op[2] = 0; st->name[2] = "Rotation";
st->op[3] = 1; st->name[3] = "Horizontal asymptote";
st->op[4] = 0; st->name[4] = "Vertical asymptote";
st->op[5] = 1; st->name[5] = "Vertical asymptote right";
st->op[6] = 1; st->name[6] = "Squirge x";
st->op[7] = 1; st->name[7] = "Squirge y";
st->op[0] = 0; st->name[0] = "Split number (inactive)";
st->op[8] = 0; st->name[8] = "Split velocity x";
st->op[9] = 0; st->name[9] = "Split velocity y";
st->op[10] = 0; st->name[10] = "Horizontal wave amplitude";
st->op[11] = myrnd()*3.141; st->name[11] = "Horizontal wave phase (inactive)";
st->op[12] = 0.01; st->name[12] = "Horizontal wave frequency (inactive)";
st->op[13] = 0; st->name[13] = "Vertical wave amplitude";
st->op[14] = myrnd()*3.141; st->name[14] = "Vertical wave phase (inactive)";
st->op[15] = 0.01; st->name[15] = "Vertical wave frequency (inactive)";
/* Initialise parameters to optimum, all off */
for (st->f=0;st->f<fs;st->f++) {
st->var[st->f]=st->op[st->f];
st->fon[st->f]=( myrnd()>0.5 ? 1 : 0 );
st->acc[st->f]=0.02 * myrnd();
st->vel[st->f]=0;
}
/* Initialise stars */
for (st->p=0;st->p<st->ps;st->p++)
stars_newp(st, st->p);
/* tx[nt],ty[nt] remember earlier screen plots (tails of stars)
which are deleted when nt comes round again */
st->nt = 0;
st->resets = 0;
st->hue = 180 + 180*myrnd();
gettimeofday(&st->lastframe, NULL);
}
if (myrnd()>0.75) {
/* Change one of the allocated colours to something near the current hue. */
/* By changing a random colour, we sometimes get a tight colour spread, sometime a diverse one. */
int pp = st->colsavailable * (0.5+myrnd()/2);
hsv_to_rgb (st->hue, .6+.4*myrnd(), .6+.4*myrnd(), &st->color[pp].red, &st->color[pp].green, &st->color[pp].blue);
if ((!mono_p) && (st->got_color = XAllocColor (st->dpy, st->xgwa.colormap, &st->color[pp]))) {
}
st->hue = st->hue + 0.5 + myrnd()*9.0;
if (st->hue<0) st->hue+=360;
if (st->hue>=360) st->hue-=360;
}
/* Move current points */
st->lastresets=st->resets;
st->resets=0;
for (st->p=0;st->p<st->ps;st->p++) {
/* Erase old */
XSetForeground (st->dpy, st->draw_gc, st->bgcolor.pixel);
/* XDrawPoint(dpy,window,draw_gc,tx[nt],ty[nt]); */
XFillRectangle(st->dpy,st->window,st->draw_gc,st->tx[st->nt],st->ty[st->nt],st->starsize,st->starsize);
/* Move */
stars_move(st, st->p);
/* If moved off screen, create a new one */
if (st->cx[st->p]<=-0.9999 || st->cx[st->p]>=+0.9999 ||
st->cy[st->p]<=-0.9999 || st->cy[st->p]>=+0.9999 ||
fabs(st->cx[st->p])<.0001 || fabs(st->cy[st->p])<.0001) {
stars_newp(st, st->p);
st->resets++;
} else if (myrnd()>0.99) /* Reset at random */
stars_newp(st, st->p);
/* Draw point */
st->sx=stars_scrpos_x(st, st->p);
st->sy=stars_scrpos_y(st, st->p);
XSetForeground (st->dpy, st->draw_gc, st->color[st->p].pixel);
/* XDrawPoint(dpy,window,draw_gc,sx,sy); */
XFillRectangle(st->dpy,st->window,st->draw_gc,st->sx,st->sy,st->starsize,st->starsize);
/* Remember it for removal later */
st->tx[st->nt]=st->sx;
st->ty[st->nt]=st->sy;
st->nt=(st->nt+1)%(st->ps*st->ts);
}
/* Adjust force fields */
st->cnt=0;
for (st->f=0;st->f<fs;st->f++) {
if (st->meters) { /* Remove meter from display */
XSetForeground(st->dpy, st->draw_gc, st->bgcolor.pixel);
stars_draw_meter(st,st->f);
}
/* Adjust forcefield's parameter */
if (st->fon[st->f]) {
/* This configuration produces var[f]s usually below 0.01 */
st->acc[st->f]=stars_perturb(st->acc[st->f],0,0.98,0.005);
st->vel[st->f]=stars_perturb(st->vel[st->f]+0.03*st->acc[st->f],0,0.995,0.0);
st->var[st->f]=st->op[st->f]+(st->var[st->f]-st->op[st->f])*0.9995+0.001*st->vel[st->f];
}
/* fprintf(stderr,"f=%i fon=%i acc=%f vel=%f var=%f\n",f,fon[f],acc[f],vel[f],var[f]); */
/* Decide whether to turn this forcefield on or off. */
/* prob_on makes the "splitting" effects less likely than the rest */
#define prob_on ( st->f==8 || st->f==9 ? 0.999975 : 0.9999 )
if ( st->fon[st->f]==0 && myrnd()>prob_on ) {
turn_on_field(st, st->f);
} else if ( st->fon[st->f]!=0 && myrnd()>0.99 && fabs(st->var[st->f]-st->op[st->f])<0.0005 && fabs(st->vel[st->f])<0.005 /* && fabs(acc[f])<0.01 */ ) {
/* We only turn it off if it has gently returned to its optimal (as opposed to rapidly passing through it). */
st->fon[st->f] = 0;
}
if (st->meters) { /* Redraw the meter */
XSetForeground(st->dpy, st->draw_gc, st->color[st->f].pixel);
stars_draw_meter(st,st->f);
}
if (st->fon[st->f])
st->cnt++;
}
/* Ensure at least three forcefields are on.
* BUG: Picking randomly might not be enough since 0,11,12,14 and 15 do nothing!
* But then what's wrong with a rare gentle twinkle?!
*/
if (st->cnt<3) {
st->f=random() % fs;
turn_on_field(st, st->f);
}
if (st->meters) {
XSetForeground(st->dpy, st->draw_gc, st->bgcolor.pixel);
XDrawRectangle(st->dpy,st->window,st->draw_gc,0,0,st->lastresets*5,3);
XSetForeground(st->dpy, st->draw_gc, st->default_fg_pixel);
XDrawRectangle(st->dpy,st->window,st->draw_gc,0,0,st->resets*5,3);
}
/* Cap frames per second; do not go above specified fps: */
{
unsigned long this_delay = 0;
int maxfps = 200;
long utimeperframe = 1000000/maxfps;
struct timeval now;
long timediff;
gettimeofday(&now, NULL);
timediff = now.tv_sec*1000000 + now.tv_usec - st->lastframe.tv_sec*1000000 - st->lastframe.tv_usec;
if (timediff < utimeperframe) {
/* fprintf(stderr,"sleeping for %i\n",utimeperframe-timediff); */
this_delay = (utimeperframe-timediff);
}
st->lastframe = now;
return this_delay;
}
}
