How can I add support for more than 4 Textures in a custom Terrain Shader

Unity Engine
,
1

Hello! I have this custom terrain shader that works great in the standard render pipeline, but doesn’t support more than 4 terrain textures (after 4 they just don’t show up). Is there an easy way to add the multi-pass support that doesn’t involve invoking the built-in terrain shader splat/cgincs?

Shader "Tome/Tome Terrain"
{
    Properties
    {
        [Header(Greyscale Area)]
        _GreyMin ("Grey Min", Range(0,1)) = 0.05
        _GreyMax ("Grey Max", Range(0,1)) = 0.5
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" "TerrainCompatible"="True"}
        LOD 200

        CGPROGRAM
        #pragma surface surf Lambert fullforwardshadows
        #pragma target 3.0
        #include "TomeGrey.cginc"

        //Splat Map
        sampler2D _Control;
        // Splat Textures
        sampler2D _Splat0, _Splat1, _Splat2, _Splat3;
        float4 _Splat0_ST, _Splat1_ST, _Splat2_ST, _Splat3_ST;
        sampler2D _Normal0, _Normal1, _Normal2, _Normal3;
        float _NormalScale0, _NormalScale1, _NormalScale2, _NormalScale3;
        float _GreyMin, _GreyMax;
        struct Input
        {
            float2 uv_Control;
            float3 worldPos;
            float3 worldNormal;
            INTERNAL_DATA
        };

        fixed4 ApplySplats(Input IN, inout SurfaceOutput o)
        {
            fixed4 splatControl = tex2D(_Control, IN.uv_Control);
            fixed4 col = splatControl.r * tex2D (_Splat0, IN.uv_Control * _Splat0_ST.xy);
            col += splatControl.g * tex2D(_Splat1, IN.uv_Control * _Splat1_ST.xy);
            col += splatControl.b * tex2D (_Splat2, IN.uv_Control * _Splat2_ST.xy);
            col += splatControl.a * tex2D (_Splat3, IN.uv_Control * _Splat3_ST.xy);
            
            o.Normal = splatControl.r * UnpackNormalWithScale(tex2D(_Normal0, IN.uv_Control * _Splat0_ST.xy), _NormalScale0);
            o.Normal += splatControl.g * UnpackNormalWithScale(tex2D(_Normal1, IN.uv_Control * _Splat1_ST.xy), _NormalScale1);
            o.Normal += splatControl.b * UnpackNormalWithScale(tex2D(_Normal2, IN.uv_Control * _Splat2_ST.xy), _NormalScale2);
            o.Normal += splatControl.a * UnpackNormalWithScale(tex2D(_Normal3, IN.uv_Control * _Splat3_ST.xy), _NormalScale3);
           
            return col;
        }

        void surf (Input IN, inout SurfaceOutput o)
        {
            fixed4 col = ApplySplats(IN, o);
           
            col = GreyscaleArea(col, IN.worldPos, _Time.y, _GreyMin, _GreyMax);
            o.Albedo = col.rgb;
            o.Alpha = col.a;
        }
        ENDCG  
    }

    FallBack "Diffuse"
}
2

Im running into the same issue with ShaderGraph terrain shaders, @blueteak , did you find a solution? Thanks!!