Update to non pointers and not working gravit

gravity.c

@@ -0,0 +1,26 @@
+#include "gravity.h"
+#include "consts.h"
+#include "vec_utils.h"
+#include <raylib.h>
+
+void gravity(universe_t *uni) {
+  mass_body_t body_1;
+  mass_body_t body_2;
+  for (unsigned int i = 0; i < uni->num_bodies - 1; i++) {
+    body_1 = uni->bodies[i];
+    for (unsigned int y = i + 1; y < uni->num_bodies; y++) {
+      body_2 = uni->bodies[y];
+      float force =
+          simx * NEWTON_G * body_1.mass * body_2.mass /
+          (vec2_len(vec2_diff(body_2.position, body_1.position)) * TIMESTEP);
+      Vector2 acceleration =
+          vec2_normalize(vec2_diff(body_2.position, body_1.position));
+      Vector2 acceleration_1 = vec2_scale(acceleration, force / body_1.mass);
+      Vector2 acceleration_2 = vec2_scale(acceleration, -force / body_2.mass);
+      body_1.speed = vec2_sum(body_1.speed, acceleration_1);
+      body_2.speed = vec2_sum(body_1.speed, acceleration_2);
+      uni->bodies[y] = body_2;
+    }
+    uni->bodies[i] = body_1;
+  }
+}