Question changing the default shader

I need to use all the advantages of the Lit terrain shader, everything suits me except for the stretched texture with a large difference in the height of the vertices, so I want to make changes to this standard shader, make a triplanar, that is, copy everything except one file and make changes to it, if not I'm wrong, this is TerrainLitPasses.hlsl , there, if I'm not mistaken, you need to change only two methods NormalMapMix and SplatmapMix...
Am I on the right track? or am i missing something?
does anyone have any advice or tips on this?
(URP, Shader Terrain Lit)

 

you could copy the shader and make an alternate version of the hlsl file and feed that in where nescessary.

 

I did just that, I made an alternative copy, now it remains to understand the most important thing - do I think correctly that it is necessary to change the NormalMapMix and SplatmapMix methods?
Am I on the right track to make the texture triplanar?

 

I have never used terrain and never will so that search is up to you my friend, but that seems correct if it's mixing textures around

Triplanar Node | Shader Graph | 6.9.2 (unity3d.com)

this could get you started on that.

 

Code (CSharp):

1.  
2. void NormalMapMix(float4 uvSplat01, float4 uvSplat23, inout half4 splatControl, inout half3 mixedNormal)
3. {
4.     #if defined(_NORMALMAP)
5.         half3 nrm = half(0.0);
6.         nrm += splatControl.r * UnpackNormalScale(SAMPLE_TEXTURE2D(_Normal0, sampler_Normal0, uvSplat01.xy), _NormalScale0);
7.         nrm += splatControl.g * UnpackNormalScale(SAMPLE_TEXTURE2D(_Normal1, sampler_Normal0, uvSplat01.zw), _NormalScale1);
8.         nrm += splatControl.b * UnpackNormalScale(SAMPLE_TEXTURE2D(_Normal2, sampler_Normal0, uvSplat23.xy), _NormalScale2);
9.         nrm += splatControl.a * UnpackNormalScale(SAMPLE_TEXTURE2D(_Normal3, sampler_Normal0, uvSplat23.zw), _NormalScale3);
10.  
11.         // avoid risk of NaN when normalizing.
12.         #if HAS_HALF
13.             nrm.z += half(0.01);
14.         #else
15.             nrm.z += 1e-5f;
16.         #endif
17.  
18.         mixedNormal = normalize(nrm.xyz);
19.     #endif
20. }
21.  
22.  
23. void SplatmapMix(float4 uvMainAndLM, float4 uvSplat01, float4 uvSplat23, inout half4 splatControl, out half weight, out half4 mixedDiffuse,
24.     out half4 defaultSmoothness, inout half3 mixedNormal, in float3 Position){
25.     half4 diffAlbedo[4];
26.  
27.     diffAlbedo[0] = SAMPLE_TEXTURE2D(_Splat0, sampler_Splat0, uvSplat01.xy);
28.     diffAlbedo[1] = SAMPLE_TEXTURE2D(_Splat1, sampler_Splat0, uvSplat01.zw);
29.     diffAlbedo[2] = SAMPLE_TEXTURE2D(_Splat2, sampler_Splat0, uvSplat23.xy);
30.     diffAlbedo[3] = SAMPLE_TEXTURE2D(_Splat3, sampler_Splat0, uvSplat23.zw);
31.  
32.     defaultSmoothness = half4(diffAlbedo[0].a, diffAlbedo[1].a, diffAlbedo[2].a, diffAlbedo[3].a);
33.     defaultSmoothness *= half4(_Smoothness0, _Smoothness1, _Smoothness2, _Smoothness3);
34.  
35.     weight = dot(splatControl, 1.0h);
36.  
37.     #ifdef TERRAIN_SPLAT_ADDPASS
38.         clip(weight <= 0.005h ? -1.0h : 1.0h);
39.     #endif
40.  
41.     #ifndef _TERRAIN_BASEMAP_GEN
42.         splatControl /= (weight + HALF_MIN);
43.     #endif
44.  
45.     mixedDiffuse = 0.0h;
46.     mixedDiffuse += diffAlbedo[0] * half4(_DiffuseRemapScale0.rgb * splatControl.rrr, 1.0h);
47.     mixedDiffuse += diffAlbedo[1] * half4(_DiffuseRemapScale1.rgb * splatControl.ggg, 1.0h);
48.     mixedDiffuse += diffAlbedo[2] * half4(_DiffuseRemapScale2.rgb * splatControl.bbb, 1.0h);
49.     mixedDiffuse += diffAlbedo[3] * half4(_DiffuseRemapScale3.rgb * splatControl.aaa, 1.0h);
50.  
51.     NormalMapMix(uvSplat01, uvSplat23, splatControl, mixedNormal);
52.     }

I just can’t figure out how to apply it correctly here, I mean triplanar, can you tell me what to do?