polypoint

// PRNG from http://burtleburtle.net/bob/rand/smallprng.html

#include "prng.h"

u4 ranval( ranctx *x ) {
	u4 e = x->a - rot(x->b, 27);
	x->a = x->b ^ rot(x->c, 17);
	x->b = x->c + x->d;
	x->c = x->d + e;
	x->d = e + x->a;
	return x->d;
}

void raninit( ranctx *x, u4 seed ) {
	u4 i;
	x->a = 0xf1ea5eed, x->b = x->c = x->d = seed;
	for (i=0; i<20; ++i) {
		(void)ranval(x);
	}
}