Scale factor and expansion upon basic implementation

src/world.h

@@ -0,0 +1,30 @@
+#ifndef WORLD_H
+#define WORLD_H
+
+#include "entity.h"
+#include "config.h"
+
+extern Entity entities[MAX_ENTITIES];
+
+extern Entity *player;
+
+extern bool isSimulating;
+
+extern float simTime;
+
+void ApplyForce(Entity *e, Vector2 force);
+bool IsGrounded(Entity *e);
+
+Entity *SpawnEntity(
+    float x,
+    float y,
+    float size,
+    float mass,
+    Color color);
+
+void ClearWorld(void);
+void InitWorld(void);
+
+int CountEntities(void);
+
+#endif