Prefabs with polygonCollider returning wrong collision normal

Cocos Creator
#1

Hello guys, I am working on multiplayer platformer game using colyseus.
I have created prefab for a character of each player which gets instantiated after matchmaking completes. After instantiation, I attach event listener to PolygonCollider of only the character of local player in following way.

–instantiation script–
instantiatePlayers(name: string) {
let tempPlayer = instantiate(this.player);
tempPlayer.name = name;
this.players.addChild(tempPlayer);
}

–only for local player–
const x = playerCharacter.getComponent(PolygonCollider2D);
x.on(
Contact2DType.BEGIN_CONTACT,
(x: Collider2D, y: Collider2D, z: IPhysics2DContact | null) => {
if (z != null) {
console.log(z.getWorldManifold());
this.socket.send(“Collision”, {
collisionVecs: {
x: z.getWorldManifold().normal.x,
y: z.getWorldManifold().normal.y,
},
speed: 20,
});
}
},
playerCharacter
);

whenever there is collision between two characters, collision event gets triggered in their indivisual machines and collision vector z gets sent to z.getWorldManifold().normal.

The vectors sent by these colliders shoud be equal and opposite in direction. But in my case, they are returning the same vectors. Because of this, the impulse I am applying on them at contact point is in same direction which is making them move in same direction after collision.

Here are few more observations,
Let’s say that the instantiated characters are A and B. A gets instantiated before B in both systems.

  1. Whenever A collides B, A will bounce back (which is correct) but B will come along with it (but B was supposed to move in opposite direction).
  2. When B collides A, again A will get pushed back (which is correct), but B will again move in the same direction which was supposed to bounce back due to collision.

Now I manually drag this character prefab into scene which gives me one more stationary object C.

  1. Whenever A collides with C, A will bounce back -correct
  2. Whenever B collides with C, B will bounce back -correct

This makes me wonder if there is any kind of problem with the collider when used with prefab or there is another way to use it.

Rigidbody and PolygonCollider info is attached in screenshot

Thank you in advance!

image
image467×816 12 KB

#2

we will solve this problem in the following issue