2D система освещения для Unity3D, работающая на GPU

Shader "Light2D/Light 9 Points" {
Properties {
	_MainTex ("Light texture", 2D) = "white" {}
	_ObstacleMul ("Obstacle Mul", Float) = 500
	_EmissionColorMul ("Emission color mul", Float) = 1
}
SubShader {	
	Tags {"Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent"}

	LOD 100
	Blend OneMinusDstColor One
	Cull Off
	ZWrite Off
	Lighting Off

	Pass {  
		CGPROGRAM
			// Upgrade NOTE: excluded shader from DX11 and Xbox360; has structs without semantics (struct v2f members sp)
			#pragma exclude_renderers d3d11 xbox360
			#pragma vertex vert
			#pragma fragment frag
			#pragma glsl_no_auto_normalization
			
			#include "UnityCG.cginc"

			struct appdata_t {
				float4 vertex : POSITION;
				float2 texcoord : TEXCOORD0;
				fixed4 color : COLOR0;
				fixed4 normal : TEXCOORD1;
			};

			struct v2f {
				float4 vertex : SV_POSITION;
				half2 texcoord : TEXCOORD0;
				fixed4 color : COLOR0;
				half4 scrPos : TEXCOORD2;
				half4 scrPosCenter : TEXCOORD1;
			};
			
		    sampler2D _ObstacleTex;
			sampler2D _MainTex;
		 	half _ObstacleMul;
			half _EmissionColorMul;

			v2f vert (appdata_t v)
			{
				v2f o;
				o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
				o.texcoord = v.texcoord;
				o.scrPos = ComputeScreenPos(o.vertex);
				o.scrPosCenter = v.normal;
				o.color = v.color;
				return o;
			}
			
			fixed3 maximize(fixed3 vec){
				vec = max(vec, fixed3(0.01, 0.01, 0.01));
				return vec/max(vec.x, max(vec.y, vec.z));
			}

			half sum(half3 vec){
				return vec.x + vec.y + vec.z;
			}

			fixed4 frag (v2f i) : COLOR
			{
                fixed2 thisPos = (i.scrPos.xy/i.scrPos.w); 
				fixed2 centerPos = i.scrPosCenter;
				const fixed sub = 0.111111111111;

				fixed m = _ObstacleMul*length((thisPos - centerPos)*fixed2(_ScreenParams.x/_ScreenParams.y, 1)*sub);
				
				fixed4 tex = tex2D(_MainTex, i.texcoord);

				clip(tex.a - 0.005);

				fixed4 col = i.color*fixed4(tex.rgb, 1)*tex.a;
				
				fixed pos = 1;

				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);

				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);
				pos -= sub; col *= saturate(1 - tex2D(_ObstacleTex, lerp(centerPos, thisPos, pos))*m);

				col.rgb *= _EmissionColorMul;

                return col;
			}
		ENDCG
	}
}

}