initial public release.HEADfront

1 files changed, 59 insertions, 0 deletions

diff --git a/vector3.c b/vector3.c
new file mode 100644
index 0000000..933716e
--- /dev/null
+++ b/vector3.c
@@ -0,0 +1,59 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include "dat.h"
+#include "fns.h"
+
+Vector3
+Vec3(double x, double y, double z)
+{
+	return (Vector3){x, y, z};
+}
+
+Vector3
+addvec3(Vector3 v, Vector3 u)
+{
+	return (Vector3){v.x+u.x, v.y+u.y, v.z+u.z};
+}
+
+Vector3
+subvec3(Vector3 v, Vector3 u)
+{
+	return (Vector3){v.x-u.x, v.y-u.y, v.z-u.z};
+}
+
+Vector3
+mulvec3(Vector3 v, double s)
+{
+	return (Vector3){v.x*s, v.y*s, v.z*s};
+}
+
+double
+dotvec3(Vector3 v, Vector3 u)
+{
+	return v.x*u.x + v.y*u.y + v.z*u.z;
+}
+
+Vector3
+crossvec(Vector3 v, Vector3 u)
+{
+	return (Vector3){
+		v.y*u.z - v.z*u.y,
+		v.z*u.x - v.x*u.z,
+		v.x*u.y - v.y*u.x
+	};
+}
+
+Vector3
+normvec3(Vector3 v)
+{
+	double len;
+
+	len = hypot3(v.x, v.y, v.z);
+	if(len == 0)
+		return (Vector3){0, 0, 0};
+	v.x /= len;
+	v.y /= len;
+	v.z /= len;
+	return v;
+}