Multiple normal maps without blending

Unity Engine
1

Hello!

My shader uses 5 textures. A mask with only RGBA informantion and the others are textures that will be rendered only in his respective channel. (ex: a texture placed in R will be showed only in the Red part of the mask painted in the object)

I use this to made terrain paint in my own meshes without use Unity’s terrain.

I’m having problems trying to implement individual normalmaps to each R G B A textures. The maximum I figure out to do is applying a normalmap that influences the whole object or blending them but none of that is what I want.

Anyone knows how can be done please??

My actual Shader do this:

2018328--130521--texturepaint.jpg
2018328--130521--texturepaint.jpg1920×1040 463 KB

My shader code: _Control is my mask with rgba info and _Splat0 to 1 are my terrain textures (And these bumps is my frustrate tentatives doing this part of the shader lol)

Shader "TerrainPaint/Lightmap-FirstPass" {
Properties {
    _Control ("Control (RGBA)", 2D) = "red" {}
    _Splat3 ("Layer 3 (A)", 2D) = "white" {}
    _Splat2 ("Layer 2 (B)", 2D) = "white" {}
    _Splat1 ("Layer 1 (G)", 2D) = "white" {}
    _BumpMap1 ("Bumpmap", 2D) = "bump" {}
    _Splat0 ("Layer 0 (R)", 2D) = "white" {}
    _BumpMap0 ("Bumpmap", 2D) = "bump" {}
    // used in fallback on old cardsus
    _MainTex ("BaseMap (RGB)", 2D) = "white" {}
    _Color ("Main Color", Color) = (1,1,1,1)
}
   
SubShader {
    Tags {
        "SplatCount" = "4"
        "Queue" = "Geometry-100"
        "RenderType" = "Opaque"
    }
CGPROGRAM
#pragma surface surf Lambert
struct Input {
    float2 uv_Control : TEXCOORD0;
    float2 uv_Splat0 : TEXCOORD1;
    float2 uv_Splat1 : TEXCOORD2;
    float2 uv_Splat2 : TEXCOORD3;
    float2 uv_Splat3 : TEXCOORD4;
    float2 uv_BumpMap0;
    float2 uv_BumpMap1;
};

sampler2D _Control;
sampler2D _Splat0,_Splat1,_Splat2,_Splat3, _BumpMap0;

void surf (Input IN, inout SurfaceOutput o) {
    half4 splat_control = tex2D (_Control, IN.uv_Control);
    half3 col;
       
    col  = splat_control.r * tex2D (_Splat0, IN.uv_Splat0).rgb;
    col += splat_control.g * tex2D (_Splat1, IN.uv_Splat1).rgb;
    col += splat_control.b * tex2D (_Splat2, IN.uv_Splat2).rgb;
    col += splat_control.a * tex2D (_Splat3, IN.uv_Splat3).rgb;
   
    o.Albedo = col;
    o.Normal = UnpackNormal (tex2D (_BumpMap0, IN.uv_BumpMap0));
    o.Alpha = 0.0;
   
   
}
ENDCG 
}

// Fallback to Diffuse
Fallback "Diffuse"
}

Frustrated result: it was not for the cobbles normalmap influence in the ground one.

2018328--130523--nrmtexturepaint.jpg
2018328--130523--nrmtexturepaint.jpg1920×1040 635 KB

Unity version: 4.3.1f

Thank you very much!

2

UPDATE

I just got how to separete normal maps in diferent parts, but now I stuck in two problems…
1 - Normal influence desapear around the shadows of the objects in the scene (picture below)

2018468--130534--texturepaint02.jpg
2018468--130534--texturepaint02.jpg1920×1040 446 KB

2 - It’s working only with two channels, if I place to calculate another (commented line 55 and 58) I got the error message: Too many interpolators used (maybe you want #pragma target 3.0?) at line 64

Shader "TerrainPaint/Lightmap-FirstPass" {
Properties {
    _Control ("Control (RGBA)", 2D) = "red" {}
    _Splat3 ("Layer 3 (A)", 2D) = "white" {}
    _BumpMap3 ("Bumpmap", 2D) = "bump" {}
    _Splat2 ("Layer 2 (B)", 2D) = "white" {}
    _BumpMap2 ("Bumpmap", 2D) = "bump" {}
    _Splat1 ("Layer 1 (G)", 2D) = "white" {}
    _BumpMap1 ("Bumpmap", 2D) = "bump" {}
    _Splat0 ("Layer 0 (R)", 2D) = "white" {}
    _BumpMap0 ("Bumpmap", 2D) = "bump" {}
    // used in fallback on old cardsus
    _MainTex ("BaseMap (RGB)", 2D) = "white" {}
    _Color ("Main Color", Color) = (1,1,1,1)
}
  
SubShader {
    Tags {
        "SplatCount" = "4"
        "Queue" = "Geometry-100"
        "RenderType" = "Opaque"
    }
CGPROGRAM
#pragma surface surf Lambert
//#pragma target 3.0
struct Input {
    float2 uv_Control : TEXCOORD0;
    float2 uv_Splat0 : TEXCOORD1;
    float2 uv_Splat1 : TEXCOORD2;
    float2 uv_Splat2 : TEXCOORD3;
    float2 uv_Splat3 : TEXCOORD4;
    float2 uv_BumpMap0;
    float2 uv_BumpMap1;
    float2 uv_BumpMap2;
    float2 uv_BumpMap3;
    //INTERNAL_DATA
  
};


sampler2D _Control;
sampler2D _Splat0,_Splat1,_Splat2,_Splat3, _BumpMap0, _BumpMap1, _BumpMap2, _BumpMap3;

void surf (Input IN, inout SurfaceOutput o) {
    half4 splat_control = tex2D (_Control, IN.uv_Control);
    half3 col;
      
    col  = splat_control.r * tex2D (_Splat0, IN.uv_Splat0).rgb;
    col += splat_control.g * tex2D (_Splat1, IN.uv_Splat1).rgb;
    col += splat_control.b * tex2D (_Splat2, IN.uv_Splat2).rgb;
    col += splat_control.a * tex2D (_Splat3, IN.uv_Splat3).rgb;
      
    o.Albedo = col;
    fixed3 normal_1 = (splat_control.r * UnpackNormal (tex2D (_BumpMap0, IN.uv_BumpMap0))) + (splat_control.g * UnpackNormal (tex2D (_BumpMap1, IN.uv_BumpMap1)));  
    //fixed3 normal_2 = (splat_control.g * UnpackNormal (tex2D (_BumpMap2, IN.uv_BumpMap2))) + (splat_control.a * UnpackNormal (tex2D (_BumpMap3, IN.uv_BumpMap3)));  
  
    o.Normal = normal_1;
    //           +normal_2;
    o.Alpha = 0.0;
  
  
}
ENDCG
}

// Fallback to Diffuse
Fallback "Diffuse"
}

Anyone knows how to solve these issues?

3

Normals influence how light diffuses into the surface, shadows are the absence of light so it only makes sense to get no effect when inside shadows.