Import sources from 2011-03-30 iso image

1 files changed, 217 insertions, 0 deletions

diff --git a/sys/src/games/juggle.c b/sys/src/games/juggle.c
new file mode 100755
index 000000000..01dea4146
--- /dev/null
+++ b/sys/src/games/juggle.c
@@ -0,0 +1,217 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <event.h>
+
+enum
+{
+	NSTEP		= 10,		/* number of steps between throws */
+	RBALL		= 10,		/* radius of ball images */
+	Nball		= 100,
+};
+
+Image *image, **disk;
+int ndisk=0;
+int nhand=2;
+int delay=20;			/* ms delay between steps */
+int nball;
+int maxhgt;
+Rectangle win;
+
+
+#define add addpt
+#define sub subpt
+#define inset insetrect
+
+
+/*
+ * pattern lists the heights of a repeating sequence of throws.
+ * At time t, hand t%nhand throws.  At that time, it must
+ * hold exactly one ball, unless it executes a 0 throw,
+ * in which case it must hold no ball.  A throw of height h
+ * at time t lands at time t+h in hand (t+h)%nhand.
+ */
+typedef struct Ball Ball;
+struct Ball{
+	int oldhand;	/* hand that previously held the ball */
+	int hgt;	/* how high the throw from oldhand was */
+	int time;	/* time at which ball will arrive */
+	int hand;	/* hand in which ball will rest on arrival */
+};
+Ball ball[Nball];
+void throw(int t, int hgt){
+	int hand=t%nhand;
+	int i, b, n;
+	b=n=0;
+	for(i=0;i!=nball;i++) if(ball[i].hand==hand && ball[i].time<=t){
+		n++;
+		b=i;
+	}
+	if(hgt==0){
+		if(n!=0){
+			print("bad zero throw at t=%d, nball=%d\n", t, n);
+			exits("bad");
+		}
+	}
+	else if(n!=1){
+		print("bad ball count at t=%d, nball=%d\n", t, n);
+		exits("bad");
+	}
+	else{
+		ball[b].oldhand=hand;
+		ball[b].hgt=hgt;
+		ball[b].time=t+hgt;
+		ball[b].hand=(hand+hgt)%nhand;
+	}
+}
+Point bpos(int b, int step, int t){
+	Ball *bp=&ball[b];
+	double dt=t-1+(step+1.)/NSTEP-(bp->time-bp->hgt);
+	double hgt=(bp->hgt*dt-dt*dt)*4./(maxhgt*maxhgt);
+	double alpha=(bp->oldhand+(bp->hand-bp->oldhand)*dt/bp->hgt)/(nhand-1);
+	return (Point){win.min.x+(win.max.x-win.min.x)*alpha,
+		       win.max.y-1+(win.min.y-win.max.y)*hgt};
+}
+
+void move(int t){
+	int i, j;
+	for(i=0;i!=NSTEP;i++){
+		if(ecanmouse()) emouse();
+		draw(image, inset(image->r, 3), display->white, nil, ZP);
+		for(j=0;j!=nball;j++)
+			fillellipse(image, bpos(j, i, t), RBALL, RBALL, disk[j%ndisk], ZP);
+		draw(screen, screen->r, image, nil, image->r.min);
+		flushimage(display, 1);
+		if(delay>0)
+			sleep(delay);
+	}
+}
+
+void
+adddisk(int c)
+{
+	Image *col;
+	disk = realloc(disk, (ndisk+1)*sizeof(Image*));
+	col=allocimage(display, Rect(0,0,1,1), CMAP8, 1, c);
+	disk[ndisk]=col;
+	ndisk++;
+}
+
+void
+diskinit(void)
+{
+	/* colors taken from /sys/src/cmd/stats.c */
+
+	adddisk(0xFFAAAAFF);
+	adddisk(DPalegreygreen);
+	adddisk(DDarkyellow);
+	adddisk(DMedgreen);
+	adddisk(0x00AAFFFF);
+	adddisk(0xCCCCCCFF);
+
+	adddisk(0xBB5D5DFF);
+	adddisk(DPurpleblue);
+	adddisk(DYellowgreen);
+	adddisk(DDarkgreen);
+	adddisk(0x0088CCFF);
+	adddisk(0x888888FF);
+}
+
+void
+usage(char *name)
+{
+	fprint(2, "usage: %s [start] pattern\n", name);
+	exits("usage");
+}
+
+void 
+eresized(int new){
+	if(new && getwindow(display, Refnone) < 0) {
+		sysfatal("can't reattach to window");
+	}
+	if(image) freeimage(image);
+	image=allocimage(display, screen->r, screen->chan, 0, DNofill);
+	draw(image, image->r, display->black, nil, ZP);
+	win=inset(screen->r, 4+2*RBALL);
+}
+void
+main(int argc, char *argv[]){
+	int sum, i, t, hgt, nstart, npattern;
+	char *s, *start = nil, *pattern = nil;
+
+	ARGBEGIN{
+	default:
+		usage(argv0);
+	case 'd':
+		s = ARGF();
+		if(s == nil)
+			usage(argv0);
+		delay = strtol(argv[0], &s, 0);
+		if(delay < 0 || s == argv[0] || *s != '\0')
+			usage(argv0);
+		break;
+	case 'h':
+		s = ARGF();
+		if(s == nil)
+			usage(argv0);
+		nhand = strtol(argv[0], &s, 0);
+		if(nhand <= 0 || s == argv[0] || *s != '\0')
+			usage(argv0);
+		break;
+	}ARGEND
+	
+	switch(argc) {
+	case 1: 
+			start=""; 
+			pattern=argv[0]; 
+			break;
+	case 2: 
+			start=argv[0]; 
+			pattern=argv[1]; 
+			break;
+	default: 
+			usage(argv0);
+	}
+	sum=0;
+	maxhgt=0;
+	for(s=pattern;*s;s++){
+		hgt=*s-'0';
+		sum+=hgt;
+		if(maxhgt<hgt) maxhgt=hgt;
+	}
+	npattern=s-pattern;
+	for(s=start;*s;s++){
+		hgt=*s-'0';
+		if(maxhgt<hgt) maxhgt=hgt;
+	}
+	if(sum%npattern){
+		print("%s: non-integral ball count\n",argv[0]);
+		exits("partial ball");
+	}
+	nball=sum/npattern;
+	for(i=0;i!=nball;i++){
+		ball[i].oldhand=(i-nball)%nhand;
+		if(ball[i].oldhand<0) ball[i].oldhand+=nhand;
+		ball[i].hgt=nball;
+		ball[i].time=i;
+		ball[i].hand=i%nhand;
+	}
+	if(initdraw(nil, nil, "juggle") < 0)
+		sysfatal("initdraw failed: %r");
+	einit(Emouse);
+	diskinit();
+	eresized(0);
+	if(image==0){
+		print("can't allocate bitmap");
+		exits("no space");
+	}
+	for(t=0;start[t];t++){
+		move(t);
+		throw(t, start[t]-'0');
+	}
+	nstart=t;
+	for(;;t++){
+		move(t);
+		throw(t, pattern[(t-nstart)%npattern]-'0');
+	}
+}