Skinned Mesh Renderer: How are the texture coordinates

[Kajos]

I am trying to apply a shader to a Skinned Mesh Renderer. However I have no idea how Unity calculates the Texture coordinates for Skinned Mesh Renderers. I have the feeling some sort of atlassing is used. Can someone give me an example or an explanation on the texture coordinates of a Skinned Mesh Renderer?

Preferably I am looking for a texture coordinate which isn’t used twice (so not mirrored), but any help would be great either way!

Shader “Clipping/Texture Clipped” {
Properties {
_MainTex (“Base (RGB)”, 2D) = “white” {}
_ClipTex (“Clip (RGB)”, 2D) = “white” {}
_InnerTex (“Inner (RGB)”, 2D) = “white” {}
}
SubShader {
Pass {
Cull Back

	CGPROGRAM
	#pragma exclude_renderers gles
	#pragma vertex vert
	#pragma fragment frag
	#include "UnityCG.cginc"
	
	struct v2f {
		float4 pos : SV_POSITION;
		float2 uv[2] : TEXCOORD0;
		float4 color : COLOR0;
	};
		uniform sampler2D _InnerTex;
		uniform float4 _InnerTex_ST;
		uniform sampler2D _ClipTex;
		uniform sampler2D _MainTex;
		uniform float4 _MainTex_ST;
	
	v2f vert( appdata_base v ) {
		v2f o;
		o.pos = mul (UNITY_MATRIX_MVP, v.vertex);
		
		o.uv[0] = v.texcoord;
		o.uv[1] = v.texcoord;
		o.uv[1].x /= 2.0;
		
		// lighting from single directional light + ambient
		float4 color = UNITY_LIGHTMODEL_AMBIENT;
		float3 lightDir = mul( glstate.light[0].position.xyz, (float3x3)UNITY_MATRIX_IT_MV );
		float ndotl = max( 0, dot( lightDir, v.normal ) );
		color.xyz += glstate.light[0].diffuse * ndotl;
		o.color = color;
		return o;
	}
	
	void frag(v2f IN, out float4 finalColor : COLOR) {
		float a = tex2D(_ClipTex, IN.uv[1].xy);
		if (a < 0.1)
			discard;
	
		finalColor = IN.color * tex2D(_MainTex, TRANSFORM_TEX(IN.uv[0].xy, _MainTex));
	}
	
	ENDCG
	
			AlphaTest Greater 0.1
			SetTexture [_MainTex] {
				Combine texture * primary DOUBLE, texture * primary
			}
			SetTexture [_ClipTex] { Combine previous, texture }
}
	
Pass {
	Cull Front 
	
	CGPROGRAM
	#pragma exclude_renderers gles
	#pragma vertex vert
	#pragma fragment frag
	#include "UnityCG.cginc"
	
	struct v2f {
		float4 pos : SV_POSITION;
		float2 uv[2] : TEXCOORD0;
		float4 color : COLOR0;
	};
		uniform sampler2D _InnerTex;
		uniform float4 _InnerTex_ST;
		uniform sampler2D _ClipTex;
		uniform sampler2D _MainTex;
		uniform float4 _MainTex_ST;
	
	v2f vert( appdata_base v ) {
		v2f o;
		o.pos = mul (UNITY_MATRIX_MVP, v.vertex);
		
		o.uv[0] = v.texcoord;
		o.uv[1] = v.texcoord;
		o.uv[1].x /= 2.0;
		
		// lighting from single directional light + ambient
		float4 color = UNITY_LIGHTMODEL_AMBIENT;
		float3 lightDir = mul( glstate.light[0].position.xyz, (float3x3)UNITY_MATRIX_IT_MV );
		float ndotl = max( 0, dot( lightDir, v.normal ) );
		color.xyz += glstate.light[0].diffuse * ndotl;
		o.color = color;
		return o;
	}
	
	void frag(v2f IN, out float4 finalColor : COLOR) {
		float a = tex2D(_ClipTex, IN.uv[0].xy);
		if (a < 0.1)
			discard;
	
		finalColor = IN.color * tex2D(_InnerTex, TRANSFORM_TEX(IN.uv[0].xy, _InnerTex));
	}
	
	ENDCG
	
			AlphaTest Greater 0.1
			SetTexture [_MainTex] {
				Combine texture * primary DOUBLE, texture * primary
			}
			SetTexture [_ClipTex] { Combine previous, texture }
	}
	
} 
Fallback "VertexLit"
  }

If I divide uv[1].x by 2 I get this however:

[whydoidoit]

There is no difference between texture coordinates in MeshRenderers and SkinnedMeshRenderers and no atlasing is performed automatically by Unity. The uvs of a mesh are associated with vertices and all a SkinnedMeshRenderer does is apply the bone weights to reposition the vertices, the uv coordinates move with them.