Kick-able Object (Unity c#)

A simple script you can use to make objects be “kicked” by your Player Character in Unity, with settings to adjust the behavior.

The object needs to have a Rigidbody and a BoxCollider Attached for the script to work.

In the Start() function the script automatically creates a box collider as trigger volume. This code can be easily optimized by removing this and manually adding a trigger volume to the object. But I want things simple and fool proof!

Example of thow the script might work on this cool skeleton we created!

Copy the code below and create a new class called MovedByPlayerMovement or download the file at the bottom of the page!

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[RequireComponent(typeof(BoxCollider))]
[RequireComponent(typeof(Rigidbody))]
public class MovedByPlayerMovement : MonoBehaviour
{
    [SerializeField] private float baseForce = 10f;
    [SerializeField] private float forceVariation = 5f;
    [SerializeField] private float directionVariation = 30f;
    [SerializeField] private float triggerVolumeSize = 1f;

    private const string PLAYERTAG = "Player";
    private Rigidbody rb;

    private void Start()
    {
        if (rb == null)
            rb = GetComponent<Rigidbody>();

        //Create a new BoxCollider to trigger the effect
        BoxCollider existingCollider = GetComponent<BoxCollider>();
        if (existingCollider != null)
        {
            //Create a new Collider
            BoxCollider newCollider = gameObject.AddComponent<BoxCollider>();

            //Center it at the original Collider and make the size bigger
            newCollider.center = existingCollider.center;
            newCollider.size = existingCollider.size * (1 + triggerVolumeSize);

            //Set it to trigger so OnTriggerEnter() triggers
            newCollider.isTrigger = true;
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        // Check if the object collided with the player
        if (other.CompareTag(PLAYERTAG))
        {
            Debug.Log("Hit by the player " + gameObject.name + "");

            Vector3 playerVelocity = PlayerStateMachine.GetInstance().CharacterController.velocity;
            Vector3 launchDirection = playerVelocity.normalized;

            // Add random variation to the launch direction
            launchDirection = Quaternion.Euler(
                Random.Range(-directionVariation, directionVariation),
                Random.Range(5, directionVariation), //This ensures the object always moves UP
                Random.Range(-directionVariation, directionVariation)
            ) * launchDirection;

            // Calculate the force with some variation
            float forceMagnitude = baseForce + Random.Range(-forceVariation, forceVariation);
            Vector3 launchForce = launchDirection * forceMagnitude;

            // Apply the force and set the Rigidbody to be dynamic
            rb.isKinematic = false;
            rb.AddForce(launchForce, ForceMode.Impulse);
        }
    }
}