How to change specific material shared among specific children.

[berzerkey]

Hi there, I am encountering some trouble in my code and was hoping someone would be kind enough to assist me in wrapping my head around this.

The scene:

1 game-object with 5 child-objects, with differing materials.

• 1 child with paint.
• 2 children with plastic.
• 2 children with metal.

The goal:

To attach a script to the parent object, “The Thing” and to be able to edit ONLY the children who share the black-plastic material.

I’ve set up a few buttons, when clicked, it will run the script that’s attached to the parent object:

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

    public class PaintChange3 : MonoBehaviour {
    
    Renderer[] children;
    public Material[] plastics;


	// Use this for initialization
	void Start () 
    {

        //children is a reference to the renderers
        children = GetComponentsInChildren<Renderer>();

        foreach (Renderer rend in children)
        {
            //make array of all materials in renderer
            Material[] materials = rend.materials;
        }
    }

    //Changes Plastic
    public void ChangePlastic(Material matPlastics)
    {

        foreach (Renderer rend in children)
        {
                var mats = new Material[rend.materials.Length];
                for (var j = 0; j < rend.materials.Length; j++)
                {
                    mats[j] = matPlastics;
                }
                rend.materials = mats;
        }

        Debug.Log("Changed Plastics, Maybe?");

    }
}

The problem with my script is that it affects every child’s renderer, I do not know how to target just the plastic children. How should I approach this solution?

Thank you again!

[II_Spoon_II]

public void ChangePlastic(Material matPlastics)
{

     foreach (Renderer rend in children)
     {
             var mats = new Material[rend.materials.Length];
             for (var j = 0; j < rend.materials.Length; j++)
             {
                 //add a condition to check if the current material is blackPlastic
                 if (mats[j]==blackPlasticMaterial)
                 {
                 mats[j] = matPlastics;
                 }
             }
             rend.materials = mats;
     }