1 files changed, 38 insertions, 0 deletions
diff --git a/standard.c b/standard.c
index 801777c..5e464f6 100644
--- a/standard.c
+++ b/standard.c
@@ -135,6 +135,44 @@ int flerp(int a, int b, int t) {
 	return a + ((t * (b - a)) >> fbits);
 }
 
+void vec_nrmise(int* x, int* y) {
+	int l;
+
+	l = ((*x * *x) >> fbits) + ((*y * *y) >> fbits);
+	*x = (*x << fbits) / l;
+	*y = (*y << fbits) / l;
+}
+
+static unsigned rng_seed, n;
+
+void seed_rng(unsigned seed) {
+	rng_seed = seed;
+	n = seed;
+}
+
+unsigned get_seed() {
+	return rng_seed;
+}
+
+unsigned rng() {
+	int a;
+	unsigned r;
+
+	n++;
+
+	a = n * 15485863;
+	r = (a * a * a % 2038074743);
+	return r;
+}
+
+int rand_range(int a, int b) {
+	return a + (int)(rng() % ((unsigned)(b - a) + 1));
+}
+
+int randf() {
+	return (int)(rng() % ((1 << fbits) + 1));
+}
+
 int int_to_buf(int n, char* buf) {
 	int i, sign, t;
 	unsigned n1;