feat: shot display

src/constants/axis.ts

@@ -1,5 +1,6 @@
 import { Vector3 } from 'three';
 
+export const ZERO_VECTOR = new Vector3();
 export const I_HAT = new Vector3(1, 0, 0);
 export const J_HAT = new Vector3(0, 1, 0);
 export const K_HAT = new Vector3(0, 0, 1);