Splat map gradient effect

Hey there,

I'm coming in relatively new to shaders have managed to piece together a simple triplaner shader from some examples, but need some assistance/advice on how to create a gradient effect from multiple different textures.

I have has some success when an image draws over another, but I'm a bit lost on how i would make this work in a gradient sense.

Here is how it works currently..




Heres the current code:

Code (c#):

1.  
2. Shader "Custom/Terrain" {
3.     Properties {
4.         _Color ("Color", Color) = (1,1,1,1)
5.         _MainTex ("Terrain Texture Array", 2DArray) = "white" {}
6.         _Glossiness ("Smoothness", Range(0,1)) = 0.5
7.         _Metallic ("Metallic", Range(0,1)) = 0.0
8.     }
9.     SubShader {
10.         Tags { "RenderType"="Opaque" }
11.         LOD 200
12.        
13.         CGPROGRAM
14.         #pragma surface surf Standard fullforwardshadows vertex:vert
15.         #pragma target 3.5
16.         #include "UnityCG.cginc"
17.         UNITY_DECLARE_TEX2DARRAY(_MainTex);
18.  
19.         half _Glossiness;
20.         half _Metallic;
21.         fixed4 _Color;
22.         uniform sampler2D _Control;
23.         struct Input {
24.             float4 color : COLOR;
25.             float3 worldPos;
26.             float3 terrain;
27.             float3 worldNormal;
28.         };
29.  
30.         void vert (inout appdata_full v, out Input data) {
31.             UNITY_INITIALIZE_OUTPUT(Input, data);
32.             data.terrain = v.texcoord2.xyz;
33.         }
34.  
35.         float4 GetTerrainColor (Input IN, int index) {
36.             float mult = 1;
37.             float3 blend = abs(IN.worldNormal);
38.             blend /= dot(blend, 1.0);
39.             float3 ux = float3(IN.worldPos.zy * mult, IN.terrain[index]);
40.             float3 uy = float3(IN.worldPos.xz * mult, IN.terrain[index]);
41.             float3 uz = float3(IN.worldPos.xy * mult, IN.terrain[index]);
42.            
43.             fixed4 cx = UNITY_SAMPLE_TEX2DARRAY(_MainTex, ux);
44.             fixed4 cy = UNITY_SAMPLE_TEX2DARRAY(_MainTex, uy);
45.             fixed4 cz = UNITY_SAMPLE_TEX2DARRAY(_MainTex, uz);
46.  
47.             fixed4 blended = cx * blend.x + cy * blend.y + cz * blend.z;
48.             fixed3 c = IN.color[index] * blend;
49.  
50.             return blended * IN.color[index];
51.         }
52.  
53.         void surf (Input IN, inout SurfaceOutputStandard o) {
54.             fixed4 splat_control = tex2D(_Control, IN.worldPos);
55.              
56.             fixed4 c = splat_control * GetTerrainColor(IN, 0);
57.             c += splat_control * GetTerrainColor(IN, 1);
58.             c += splat_control.a * GetTerrainColor(IN, 2);
59.  
60.             o.Albedo = c.rgb * _Color;
61.             o.Metallic = _Metallic;
62.             o.Smoothness = _Glossiness;
63.             o.Alpha = c.a;
64.         }
65.         ENDCG
66.     }
67.     FallBack "Diffuse"
68. }
69.  

The furthest i hope to extend this is to also include normal maps and specular maps for some context on where i am going on this, so if you see any red flags for this, an early warning would also be greatly appreciated.

But ultimately, for this question in particular. Does anyone have a suggestion on how i can get a more gradient effect between the textures?

 

Did you check out the Unity's built in terrain shader source? It shows exactly how it does its blending.