ref: 94d2ee527af44610a498d6f6adbba8f0b6d76f17
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; }