Quick shader to debug texture coordinates of a given mesh

unity_DebugUVs.shader

Shader "Custom/DebugUVs" {
    SubShader {
        Pass {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"

            struct v2f {
                float4 pos : SV_POSITION;
                fixed3 color : COLOR0;
            };

            v2f vert (appdata_base v)
            {
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.color = v.texcoord;
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                return fixed4 (i.color, 1);
            }

            ENDCG
        }
    }
}