using UnityEngine;

[AddComponentMenu("Image Effects/Rain/ShowerEffect")]
[ExecuteInEditMode]
public class ShowerEffect : MonoBehaviour
{
	private Material mat;

	public Shader shader;

	public Texture2D NormalMap;

	[Range(0.01f, 1.5f)]
	public float alpha = 0.03f;

	[Range(0.05f, 2f)]
	public float intensity = 1f;

	[Range(0.05f, 2f)]
	public float scrollSpeed = 0.5f;

	private float scrollPos;

	private void Awake()
	{
		if (!shader)
		{
			shader = Resources.Load("ShowerEffectShader", typeof(Shader)) as Shader;
		}
		if (!NormalMap)
		{
			NormalMap = Resources.Load("NormShower", typeof(Texture2D)) as Texture2D;
		}
		mat = new Material(shader);
		mat.SetTexture("_NormalTex", NormalMap);
	}

	public void Update()
	{
		scrollPos += Time.deltaTime * scrollSpeed;
	}

	private void OnRenderImage(RenderTexture source, RenderTexture destination)
	{
		mat.SetTexture("_NormalTex", NormalMap);
		mat.SetFloat("_Intensity", intensity);
		mat.SetFloat("_Alpha", alpha);
		mat.SetVector("_OffsetScale", new Vector4(0f, scrollPos, (float)Screen.width / (float)NormalMap.width, (float)Screen.height / (float)NormalMap.height));
		Graphics.Blit(source, destination, mat);
	}
}