diff --git a/cphysics.c b/cphysics.c
new file mode 100644
index 0000000..9f920e2
--- /dev/null
+++ b/cphysics.c
@@ -0,0 +1,8 @@
+#include "cphysics.h"
+
+void gravity(universe_t* univ){
+
+}
+void magnetism(universe_t* univ){
+
+}
diff --git a/cphysics.h b/cphysics.h
new file mode 100644
index 0000000..80b6944
--- /dev/null
+++ b/cphysics.h
@@ -0,0 +1,7 @@
+#ifndef CPHYSICS_H_
+#define CPHYSICS_H_
+#include "objects.h"
+void gravity(universe_t* univ);
+void magnetism(universe_t* univ);
+void mechanics(universe_t* univ);
+#endif // CPHYSICS_H_
diff --git a/main.c b/main.c
index cdea2fe..6d349e9 100644
--- a/main.c
+++ b/main.c
@@ -3,6 +3,7 @@
 #include <bits/time.h>
 #include <math.h>
 #include <pthread.h>
+#include <unistd.h>
 #include <raylib.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -130,10 +131,6 @@ bool vec2_is_null(Vector2 v) {
   return false;
 }
 
-typedef struct universe {
-  unsigned int num_bodies;
-  mass_body_t *bodies;
-} universe_t;
 
 long long timespec_diff_ns(struct timespec end, struct timespec start) {
   return (end.tv_sec - start.tv_sec) * 1000000000LL +
diff --git a/objects.h b/objects.h
new file mode 100644
index 0000000..d194f5c
--- /dev/null
+++ b/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_
diff --git a/vec_util.h b/vec_util.h
new file mode 100644
index 0000000..dc45509
--- /dev/null
+++ b/vec_util.h
@@ -0,0 +1,42 @@
+#ifndef VEC_UTIL_H_
+#define VEC_UTIL_H_
+#include <raylib.h>
+#include <math.h>
+static const Vector2 NULL_VEC2 = {0, 0};
+
+
+
+Vector2 transform_to_center(Vector2 v) {
+  int width = GetRenderWidth();
+  int height = GetRenderHeight();
+  Vector2 result = {v.x + width / 2.0, v.y + height / 2.0};
+  return result;
+}
+
+Vector2 vec2_sum(const Vector2 *a, const Vector2 *b) {
+  Vector2 result = {a->x + b->x, a->y + b->y};
+  return result;
+}
+Vector2 vec2_diff(const Vector2 *a, const Vector2 *b) {
+  Vector2 result = {a->x - b->x, a->y - b->y};
+  return result;
+}
+
+float vec2_len(Vector2 v) { return sqrtf(v.x * v.x + v.y * v.y); }
+
+Vector2 vec2_normalize(const Vector2 v) {
+  float len = vec2_len(v);
+  Vector2 result = {v.x / len, v.y / len};
+  return result;
+}
+
+Vector2 vec2_scale(const Vector2 *normal, const float len) {
+  Vector2 result = {len * normal->x, len * normal->y};
+  return result;
+}
+
+float vec2_dot(const Vector2 *a, const Vector2 *b) {
+  return a->x * b->x + a->y * b->y;
+}
+
+#endif // VEC_UTIL_H_