MoonlightVRC/Shader/LitParticles.shader

Shader "DeMuenu/World/Hoppou/Particles/LitParticles"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _Color ("Color", Color) = (1,1,1,1)

        
        //MoonsLight
        _InverseSqareMultiplier ("Inverse Square Multiplier", Float) = 1
        _LightCutoffDistance ("Light Cutoff Distance", Float) = 100
        //MoonsLight END



    }
    SubShader
    {
        Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" "PreviewType"="Plane" }
        Blend SrcAlpha One
        Cull Off
        Lighting Off
        ZWrite Off
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            #define MAX_LIGHTS 80 // >= maxPlayers in script

            #include "UnityCG.cginc"



            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;

                float4 color  : COLOR;

                float3 normal : NORMAL;

            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
                //MoonsLight
                float3 worldPos : TEXCOORD2;

                float4 color : COLOR;

                float3 worldNormal: TEXCOORD3;
                //MoonsLight END
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;
            sampler2D _MultTex;
            float4 _MultTex_ST;
            float4 _Color;


            sampler2D _EmmisiveText;
            float4 _EmmisiveText_ST;
            float4 _EmmissiveColor;
            float _EmmissiveStrength;


            //MoonsLight
            float _InverseSqareMultiplier;
            float _LightCutoffDistance;            
            
            float4 _LightPositions[MAX_LIGHTS]; // xyz = position
            float4 _LightColors[MAX_LIGHTS]; // xyz = position
            float4 _LightDirections[MAX_LIGHTS]; // xyz = direction, w = cos(halfAngle)
            float _LightType[MAX_LIGHTS]; // 0 = sphere, 1 = cone
            float  _PlayerCount;                  // set via SetFloat
            //MoonsLight END


            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);


                //MoonsLight
                float4 wp = mul(unity_ObjectToWorld, v.vertex);
                o.worldPos = wp.xyz;
                o.color = v.color;
                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                //MoonsLight END
                

                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                // sample the texture
                fixed4 col = tex2D(_MainTex, i.uv);


                //MoonsLight
                int count = (int)_PlayerCount;

                float3 N = normalize(i.worldNormal); //for lambertian diffuse
                // Example: compute distance to nearest player
                float4 dmax = float4(0,0,0,1);
                float dIntensity = 0;
                [loop]
                for (int idx = 0; idx < MAX_LIGHTS; idx++)
                {
                    if (idx >= count) break;
                    float radius = _LightPositions[idx].a;
                    float3 q = _LightPositions[idx].xyz;

                    float distanceFromLight = length(i.worldPos - q);
                    if (distanceFromLight > _LightCutoffDistance) continue;
                    
                    float sd = 0.0;
                    float contrib = 0.0;
                    

                    float invSqMul = max(1e-4, _InverseSqareMultiplier);
                    

                    //Lambertian diffuse
                    float3 L = normalize(q - i.worldPos);   // q = light position
                    float  NdotL = saturate(dot(N, L) * 0.5 + 0.5);      // one-sided Lambert
                    if (NdotL <= 0) continue;

                    if(_LightType[idx] == 0)
                    {
                        float invSq    = _LightColors[idx].a / max(1e-4, max(0, max(1, distanceFromLight - radius) * invSqMul) * max(0, max(1, distanceFromLight - radius) * invSqMul));
                        contrib  = invSq;
                        //contrib = contrib * step(-distance(i.worldPos, q), -1 + radius * 1); // 0 if outside sphere
                        dIntensity += contrib * NdotL;
                    }
                    else if (_LightType[idx] == 1)
                    {
                        float invSq    = _LightColors[idx].a / max(1e-4, (distanceFromLight * invSqMul) * (distanceFromLight * invSqMul));
                        float threshold = (-1 + _LightDirections[idx].w / 180);
                        
                        contrib = min(dot(normalize(i.worldPos - q), -normalize(_LightDirections[idx].xyz)), 0);
                        contrib= 1 - step(threshold, contrib);
                        
                        contrib = contrib * invSq;
                        dIntensity += contrib * NdotL;
                    }
                    float3 LightColor = _LightColors[idx].xyz; // * NormalDirMult;



                    dmax = dmax + contrib * float4(LightColor, 1) * NdotL; // accumulate light contributions

                    


                }
                
                //dmax.xyz = min(dmax * dIntensity, 1.0);
                dmax.w = 1.0;
                dmax = dmax;


                //MoonsLight END



                return col * _Color * min(dmax, 1.0) * i.color;

            }
            ENDCG
        }
    }

    FallBack "Diffuse"
}