From 9da5009cdcabdc162d84e43853439cee78467f23 Mon Sep 17 00:00:00 2001
From: Sam Anthony <sam@samanthony.xyz>
Date: Thu, 19 Sep 2024 17:54:19 -0400
Subject: better collisions

---
 vec.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 vec.c

(limited to 'vec.c')

diff --git a/vec.c b/vec.c
new file mode 100644
index 0000000..ba8edfa
--- /dev/null
+++ b/vec.c
@@ -0,0 +1,51 @@
+#include "balls.h"
+
+Vec
+vsub(Vec v1, Vec v2) {
+	return V(v1.x-v2.x, v1.y-v2.y);
+}
+
+Vec
+vmuls(Vec v, int a) {
+	return V(v.x*a, v.y*a);
+}
+
+Vec
+vdivs(Vec v, int a) {
+	if (a == 0)
+		return V(0, 0);
+	return V(v.x/a, v.y/a);
+}
+
+int
+vdot(Vec v1, Vec v2) {
+	return v1.x*v2.x + v1.y*v2.y;
+}
+
+int
+vlen(Vec v) {
+	return sqrt(v.x*v.x + v.y*v.y);
+}
+
+Vec
+unitnorm(Vec v) {
+	return vdivs(v, vlen(v));
+}
+
+Point
+ptaddv(Point p, Vec v) {
+	p.x += v.x;
+	p.y += v.y;
+	return p;
+}
+
+Vec
+V(int x, int y) {
+	Vec v = {x, y};
+	return v;
+}
+
+Vec
+Vpt(Point p, Point q) {
+	return V(p.x-q.x, p.y-q.y);
+}
-- 
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