using UnityEngine;
using System.Collections;


[ExecuteInEditMode]
[RequireComponent (typeof(Camera))]
[AddComponentMenu ("Image Effects/Displacement/Fisheye")]
class Fisheye : PostEffectsBase {
	public float strengthX = 0.05f;
	public float strengthY = 0.05f;

	public Shader fishEyeShader = null;
	private Material fisheyeMaterial = null;


    public override bool CheckResources (){	
		 CheckSupport (false);
		fisheyeMaterial = CheckShaderAndCreateMaterial(fishEyeShader,fisheyeMaterial);
		
		if(!isSupported)
			ReportAutoDisable ();
		return isSupported;			
	}
	
	void OnRenderImage ( RenderTexture source ,   RenderTexture destination  ){		
		if(CheckResources()==false) {
			Graphics.Blit (source, destination);
			return;
		}
				
		float oneOverBaseSize = 80.0f / 512.0f; // to keep values more like in the old version of fisheye
		
		float ar = (source.width * 1.0f) / (source.height * 1.0f);
		
		fisheyeMaterial.SetVector ("intensity", new Vector4 (strengthX * ar * oneOverBaseSize, strengthY * oneOverBaseSize, strengthX * ar * oneOverBaseSize, strengthY * oneOverBaseSize));
		Graphics.Blit (source, destination, fisheyeMaterial); 	
	}
}