MobileBloom

// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'


Shader "Hidden/FastBloom" {
	Properties {
		_MainTex ("Base (RGB)", 2D) = "white" {}
		_Bloom ("Bloom (RGB)", 2D) = "black" {}
	}

	CGINCLUDE

		#include "UnityCG.cginc"

		sampler2D _MainTex;
		sampler2D _Bloom;

		uniform half4 _MainTex_TexelSize;

		uniform half4 _Parameter;
		uniform half4 _OffsetsA;
		uniform half4 _OffsetsB;

		#define ONE_MINUS_THRESHHOLD_TIMES_INTENSITY _Parameter.w
		#define THRESHHOLD _Parameter.z

		struct v2f_simple
		{
			float4 pos : SV_POSITION;
			half2 uv : TEXCOORD0;

        #if UNITY_UV_STARTS_AT_TOP
				half2 uv2 : TEXCOORD1;
		#endif
		};

		v2f_simple vertBloom ( appdata_img v )
		{
			v2f_simple o;

			o.pos = UnityObjectToClipPos (v.vertex);
        	o.uv = v.texcoord;

        #if UNITY_UV_STARTS_AT_TOP
        	o.uv2 = v.texcoord;
        	if (_MainTex_TexelSize.y < 0.0)
        		o.uv.y = 1.0 - o.uv.y;
        #endif

			return o;
		}

		struct v2f_tap
		{
			float4 pos : SV_POSITION;
			half2 uv20 : TEXCOORD0;
			half2 uv21 : TEXCOORD1;
			half2 uv22 : TEXCOORD2;
			half2 uv23 : TEXCOORD3;
		};

		v2f_tap vert4Tap ( appdata_img v )
		{
			v2f_tap o;

			o.pos = UnityObjectToClipPos (v.vertex);
        	o.uv20 = v.texcoord + _MainTex_TexelSize.xy;
			o.uv21 = v.texcoord + _MainTex_TexelSize.xy * half2(-0.5h,-0.5h);
			o.uv22 = v.texcoord + _MainTex_TexelSize.xy * half2(0.5h,-0.5h);
			o.uv23 = v.texcoord + _MainTex_TexelSize.xy * half2(-0.5h,0.5h);

			return o;
		}

		fixed4 fragBloom ( v2f_simple i ) : SV_Target
		{
        	#if UNITY_UV_STARTS_AT_TOP

			fixed4 color = tex2D(_MainTex, i.uv2);
			return color + tex2D(_Bloom, i.uv);

			#else

			fixed4 color = tex2D(_MainTex, i.uv);
			return color + tex2D(_Bloom, i.uv);

			#endif
		}

		fixed4 fragDownsample ( v2f_tap i ) : SV_Target
		{
			fixed4 color = tex2D (_MainTex, i.uv20);
			color += tex2D (_MainTex, i.uv21);
			color += tex2D (_MainTex, i.uv22);
			color += tex2D (_MainTex, i.uv23);
			return max(color/4 - THRESHHOLD, 0) * ONE_MINUS_THRESHHOLD_TIMES_INTENSITY;
		}

		// weight curves

		static const half curve[7] = { 0.0205, 0.0855, 0.232, 0.324, 0.232, 0.0855, 0.0205 };  // gauss'ish blur weights

		static const half4 curve4[7] = { half4(0.0205,0.0205,0.0205,0), half4(0.0855,0.0855,0.0855,0), half4(0.232,0.232,0.232,0),
			half4(0.324,0.324,0.324,1), half4(0.232,0.232,0.232,0), half4(0.0855,0.0855,0.0855,0), half4(0.0205,0.0205,0.0205,0) };

		struct v2f_withBlurCoords8
		{
			float4 pos : SV_POSITION;
			half4 uv : TEXCOORD0;
			half2 offs : TEXCOORD1;
		};

		struct v2f_withBlurCoordsSGX
		{
			float4 pos : SV_POSITION;
			half2 uv : TEXCOORD0;
			half4 offs[3] : TEXCOORD1;
		};

		v2f_withBlurCoords8 vertBlurHorizontal (appdata_img v)
		{
			v2f_withBlurCoords8 o;
			o.pos = UnityObjectToClipPos (v.vertex);

			o.uv = half4(v.texcoord.xy,1,1);
			o.offs = _MainTex_TexelSize.xy * half2(1.0, 0.0) * _Parameter.x;

			return o;
		}

		v2f_withBlurCoords8 vertBlurVertical (appdata_img v)
		{
			v2f_withBlurCoords8 o;
			o.pos = UnityObjectToClipPos (v.vertex);

			o.uv = half4(v.texcoord.xy,1,1);
			o.offs = _MainTex_TexelSize.xy * half2(0.0, 1.0) * _Parameter.x;

			return o;
		}

		half4 fragBlur8 ( v2f_withBlurCoords8 i ) : SV_Target
		{
			half2 uv = i.uv.xy;
			half2 netFilterWidth = i.offs;
			half2 coords = uv - netFilterWidth * 3.0;

			half4 color = 0;
  			for( int l = 0; l < 7; l++ )
  			{
				half4 tap = tex2D(_MainTex, coords);
				color += tap * curve4[l];
				coords += netFilterWidth;
  			}
			return color;
		}


		v2f_withBlurCoordsSGX vertBlurHorizontalSGX (appdata_img v)
		{
			v2f_withBlurCoordsSGX o;
			o.pos = UnityObjectToClipPos (v.vertex);

			o.uv = v.texcoord.xy;
			half2 netFilterWidth = _MainTex_TexelSize.xy * half2(1.0, 0.0) * _Parameter.x;
			half4 coords = -netFilterWidth.xyxy * 3.0;

			o.offs[0] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);
			coords += netFilterWidth.xyxy;
			o.offs[1] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);
			coords += netFilterWidth.xyxy;
			o.offs[2] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);

			return o;
		}

		v2f_withBlurCoordsSGX vertBlurVerticalSGX (appdata_img v)
		{
			v2f_withBlurCoordsSGX o;
			o.pos = UnityObjectToClipPos (v.vertex);

			o.uv = half4(v.texcoord.xy,1,1);
			half2 netFilterWidth = _MainTex_TexelSize.xy * half2(0.0, 1.0) * _Parameter.x;
			half4 coords = -netFilterWidth.xyxy * 3.0;

			o.offs[0] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);
			coords += netFilterWidth.xyxy;
			o.offs[1] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);
			coords += netFilterWidth.xyxy;
			o.offs[2] = v.texcoord.xyxy + coords * half4(1.0h,1.0h,-1.0h,-1.0h);

			return o;
		}

		half4 fragBlurSGX ( v2f_withBlurCoordsSGX i ) : SV_Target
		{
			half2 uv = i.uv.xy;

			half4 color = tex2D(_MainTex, i.uv) * curve4[3];

  			for( int l = 0; l < 3; l++ )
  			{
				half4 tapA = tex2D(_MainTex, i.offs[l].xy);
				half4 tapB = tex2D(_MainTex, i.offs[l].zw);
				color += (tapA + tapB) * curve4[l];
  			}

			return color;

		}

	ENDCG

	SubShader {
	  ZTest Off Cull Off ZWrite Off Blend Off

	// 0
	Pass {

		CGPROGRAM
		#pragma vertex vertBloom
		#pragma fragment fragBloom

		ENDCG

		}

	// 1
	Pass {

		CGPROGRAM

		#pragma vertex vert4Tap
		#pragma fragment fragDownsample

		ENDCG

		}

	// 2
	Pass {
		ZTest Always
		Cull Off

		CGPROGRAM

		#pragma vertex vertBlurVertical
		#pragma fragment fragBlur8

		ENDCG
		}

	// 3
	Pass {
		ZTest Always
		Cull Off

		CGPROGRAM

		#pragma vertex vertBlurHorizontal
		#pragma fragment fragBlur8

		ENDCG
		}

	// alternate blur
	// 4
	Pass {
		ZTest Always
		Cull Off

		CGPROGRAM

		#pragma vertex vertBlurVerticalSGX
		#pragma fragment fragBlurSGX

		ENDCG
		}

	// 5
	Pass {
		ZTest Always
		Cull Off

		CGPROGRAM

		#pragma vertex vertBlurHorizontalSGX
		#pragma fragment fragBlurSGX

		ENDCG
		}
	}

	FallBack Off
}