Separating into lots of headers

objects.h

@@ -0,0 +1,16 @@
+#ifndef OBJECTS_H_
+#define OBJECTS_H_
+#include "vec_util.h"
+
+typedef struct {
+  float mass;
+  float radius;
+  Vector2 position;
+  Vector2 speed;
+} mass_body_t;
+
+typedef struct universe {
+  unsigned int num_bodies;
+  mass_body_t *bodies;
+} universe_t;
+#endif // OBJECTS_H_