summaryrefslogtreecommitdiff
path: root/vector.c
diff options
context:
space:
mode:
Diffstat (limited to 'vector.c')
-rw-r--r--vector.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/vector.c b/vector.c
new file mode 100644
index 0000000..0657845
--- /dev/null
+++ b/vector.c
@@ -0,0 +1,48 @@
+#include <u.h>
+#include <libc.h>
+#include "dat.h"
+#include "fns.h"
+
+Vector
+Vec(double x, double y, double w)
+{
+ return (Vector){x, y, w};
+}
+
+Vector
+addvec(Vector v, Vector u)
+{
+ return (Vector){v.x+u.x, v.y+u.y, v.w+u.w};
+}
+
+Vector
+subvec(Vector v, Vector u)
+{
+ return (Vector){v.x-u.x, v.y-u.y, v.w-u.w};
+}
+
+Vector
+mulvec(Vector v, double s)
+{
+ return (Vector){v.x*s, v.y*s, v.w*s};
+}
+
+double
+dotvec(Vector v, Vector u)
+{
+ return v.x*u.x + v.y*u.y + v.w*u.w;
+}
+
+Vector
+normvec(Vector v)
+{
+ double len;
+
+ len = hypot3(v.x, v.y, v.w);
+ if(len == 0)
+ return (Vector){0, 0, 0};
+ v.x /= len;
+ v.y /= len;
+ v.w /= len;
+ return v;
+}