// Colorful FX - Unity Asset
// Copyright (c) 2015 - Thomas Hourdel
// http://www.thomashourdel.com

Shader "Hidden/Colorful/Negative"
{
	Properties
	{
		_MainTex ("Base (RGB)", 2D) = "white" {}
		_Amount ("Amount (Float)", Range(0.0, 1.0)) = 1.0
	}

	CGINCLUDE

		#include "UnityCG.cginc"

		sampler2D _MainTex;
		half _Amount;

		half4 frag(v2f_img i) : SV_Target
		{
			half4 oc = tex2D(_MainTex, i.uv);
			half4 nc = 1.0 - oc;
			return lerp(oc, nc, _Amount);
		}

		half4 frag_linear(v2f_img i) : SV_Target
		{
			half4 oc = tex2D(_MainTex, i.uv);
			oc = pow(oc, 0.454545);
			half4 nc = 1.0 - oc;
			nc = pow(nc, 2.2);
			return lerp(oc, nc, _Amount);
		}

	ENDCG

	SubShader
	{
		ZTest Always Cull Off ZWrite Off
		Fog { Mode off }

		// (0) Gamma
		Pass
		{
			CGPROGRAM

				#pragma vertex vert_img
				#pragma fragment frag
				#pragma fragmentoption ARB_precision_hint_fastest 

			ENDCG
		}

		// (1) Linear
		Pass
		{
			CGPROGRAM

				#pragma vertex vert_img
				#pragma fragment frag_linear
				#pragma fragmentoption ARB_precision_hint_fastest 

			ENDCG
		}
	}

	FallBack off
}