How to make the scene darker?

Questions & Answers
1

Hi all,
There are no lights are used in our scene, objects in scene use shaders like diffuse, transparent/diffuse and Mobile/Diffuse, and actors use unlit/transparent cutout, is there any way to make the scene darker and actors unchanged, thanks in advance.

3
2

Use something like this.

alpha is the variable to make it darker.

using UnityEngine;
using System.Collections;

public class Fading : MonoBehaviour {

	/// the texture that will overlay the screen. This can be a black image or a loading graphic
	public Texture2D fadeOutTexture;

	/// <summary>
	///  the fading speed
	/// </summary>
	public float fadeSpeed = 0.5f;		

	///the texture's order in the draw hierarchy: a low number means it renders on top
	private int drawDepth = -1000;		

	/// the texture's alpha value between 0 and 1
	private float alpha = 1.0f;


	void Start()
	{
		DontDestroyOnLoad(transform);
	}

	void OnGUI()
	{

		// set color of our GUI (in this case our texture). All color values remain the same & the Alpha is set to the alpha variable
		GUI.color = new Color (GUI.color.r, GUI.color.g, GUI.color.b, alpha);
		GUI.depth = drawDepth;																// make the black texture render on top (drawn last)
		GUI.DrawTexture(new Rect(0, 0, Screen.width, Screen.height), fadeOutTexture);		// draw the texture to fit the entire screen area
	}
}