//----------------------------------------------------------------------------------------------------------
// X-PostProcessing Library
// https://github.com/QianMo/X-PostProcessing-Library
// Copyright (C) 2020 QianMo. All rights reserved.
// Licensed under the MIT License 
// You may not use this file except in compliance with the License.You may obtain a copy of the License at
// http://opensource.org/licenses/MIT
//----------------------------------------------------------------------------------------------------------

Shader "Hidden/X-PostProcessing/Glitch/RGBSplitV4"
{
	HLSLINCLUDE
	
	#include "../../../Shaders/XPostProcessing.hlsl"



	uniform half2 _Params;

	#define _Indensity _Params.x
	#define _TimeX _Params.y

	float randomNoise(float x, float y)
	{
		return frac(sin(dot(float2(x, y), float2(12.9898, 78.233))) * 43758.5453);
	}

	half4 Frag_Horizontal(VaryingsDefault i) : SV_Target
	{
		float splitAmount = _Indensity * randomNoise(_TimeX, 2);

		half4 ColorR = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x + splitAmount, i.texcoord.y));
		half4 ColorG = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.texcoord);
		half4 ColorB = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x - splitAmount, i.texcoord.y));

		return half4(ColorR.r, ColorG.g, ColorB.b, 1);
	}

	half4 Frag_Vertical(VaryingsDefault i) : SV_Target
	{

		float splitAmount =  _Indensity * randomNoise(_TimeX, 2);

		half4 ColorR = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.texcoord);
		half4 ColorG = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x, i.texcoord.y + splitAmount));
		half4 ColorB = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x, i.texcoord.y - splitAmount));

		return half4(ColorR.r, ColorG.g, ColorB.b, 1);
	}

	half4 Frag_Horizontal_Vertical(VaryingsDefault i) : SV_Target
	{

		float splitAmount = _Indensity * randomNoise(_TimeX, 2);

		half4 ColorR = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.texcoord);
		half4 ColorG = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x + splitAmount, i.texcoord.y + splitAmount));
		half4 ColorB = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, float2(i.texcoord.x - splitAmount, i.texcoord.y - splitAmount));

		return half4(ColorR.r, ColorG.g, ColorB.b, 1);
	}

	ENDHLSL
	
	SubShader
	{
		Cull Off ZWrite Off ZTest Always
		
		Pass
		{
			HLSLPROGRAM
			
			#pragma vertex VertDefault
			#pragma fragment Frag_Horizontal
			
			ENDHLSL
			
		}
		
		Pass
		{
			HLSLPROGRAM
			
			#pragma vertex VertDefault
			#pragma fragment Frag_Vertical
			
			ENDHLSL
			
		}

		Pass
		{
			HLSLPROGRAM

			#pragma vertex VertDefault
			#pragma fragment Frag_Horizontal_Vertical

			ENDHLSL

		}
	}
}