Fading blood pool on ground.

Questions & Answers
1

Hi
I have been trying to create a blood pool everytime I kill a victim
It turned out to be a bit more difficult than expected, and I fear that my end result… although it works, is not the optimal sollution. I would be very gratefull, if someone had suggestions on how to do this in a better way. So, if anyone has offers on how to improve this, please share with me.

using UnityEngine;
using System.Collections;

public class AlphaFader : MonoBehaviour
{
	public Texture2D blood;
	public Color lerpedColor;
	public bool startFading = false;
	public float trans = 1;
	

	void Start ()
	{
		//Sets the material of the gameObject
		renderer.material = new Material (Shader.Find ("Transparent/Diffuse"));
		renderer.material.SetTexture("_MainTex", blood);
		
		//Starts the corutine
		StartCoroutine(StartFading());

	}
	
	void Update ()
	{
		
		if(startFading){
			//Removes some of the trans that is used to lert the alpha of the material.
			trans = trans - Time.deltaTime * 0.2f;
			lerpedColor.a = Mathf.Lerp(0, 1, trans);
			renderer.material.color = lerpedColor;
		}
		
		//Destroys the object when the material is completly transparent.
		if (lerpedColor.a == 0)
			Destroy (this.gameObject);

	}
	
	//This will waith for a while before starting the fade of the material.
	IEnumerator StartFading (){
		yield return new WaitForSeconds(Random.value * 4.0f);
		startFading = true;	
	}
}
2

You can save some trouble by using Start as the coroutine and doing the for/time coroutine pattern (example below), but other than that I’d say your script looks fine! Only reason I suggest switching to this pattern is that it’s easier to maintain and tweak.

public class AlphaFader : MonoBehaviour
{
    public Texture2D blood;
    public float fadeTime = 3.0f;

    IEnumerator Start ()
    {
       //Sets the material of the gameObject
       renderer.material = new Material (Shader.Find ("Transparent/Diffuse"));
       renderer.material.SetTexture("_MainTex", blood);

       yield return new WaitForSeconds(Random.value * 4.0f);
    
      //Removes some of the trans that is used to lerp the alpha of the material.
      float invFadeTime = 1.0f / fadeTime;
      for(float t = 0.0f; t < fadeTime; t += Time.deltaTime)
      {
         Color bloodColor = renderer.material.color;
         bloodColor.a = Mathf.Lerp(1.0f, 0.0f, t * invFadeTime);
         renderer.material.color = bloodColor;
         yield return 0;
      }

       //Destroys the object when the material is completly transparent.
       Destroy (this.gameObject);
    }
 }