Unity3D用のGPUベースの2D照明システム

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 } } }