ref: a45dbe7a9a18a016081c5cd5492a42c8b0547f6a
dir: /sys/src/libdraw/drawrepl.c/
#include <u.h>
#include <libc.h>
#include <draw.h>
int
drawreplxy(int min, int max, int x)
{
int sx;
sx = (x-min)%(max-min);
if(sx < 0)
sx += max-min;
return sx+min;
}
Point
drawrepl(Rectangle r, Point p)
{
p.x = drawreplxy(r.min.x, r.max.x, p.x);
p.y = drawreplxy(r.min.y, r.max.y, p.y);
return p;
}