1 files changed, 61 insertions, 0 deletions
diff --git a/vec.cpp b/vec.cpp
new file mode 100644
index 0000000..a9b78e9
--- /dev/null
+++ b/vec.cpp
@@ -0,0 +1,61 @@
+#include <math.h>
+
+#include "balls.h"
+
+Vector
+addVec(Vector v1, Vector v2) {
+	v1.x += v2.x;
+	v1.y += v2.y;
+	return v1;
+}
+
+Vector
+subVec(Vector v1, Vector v2) {
+	v1.x -= v2.x;
+	v1.y -= v2.y;
+	return v1;
+}
+
+Vector
+vecMulS(Vector v, double s) {
+	v.x *= s;
+	v.y *= s;
+	return v;
+}
+
+Vector
+vecDivS(Vector v, double s) {
+	v.x /= s;
+	v.y /= s;
+	return v;
+}
+
+double
+vecDot(Vector v1, Vector v2) {
+	return v1.x*v2.x + v1.y*v2.y;
+}
+
+Vector
+unitNorm(Vector v) {
+	return vecDivS(v, vecLen(v));
+}
+
+double
+vecLen(Vector v) {
+	return sqrt(v.x*v.x + v.y*v.y);
+}
+
+Vector
+Vec(double x, double y) {
+	Vector v = {x, y};
+	return v;
+}
+
+Vector
+VecPt(Point p, Point q) {
+	double dx, dy;
+
+	dx = q.x - p.x;
+	dy = q.y - p.y;
+	return Vec(dx, dy);
+}