Tartan Shifting

Shader that changes width of every second pixel by shifting UVs.

TartanShifting.shader

Shader "Unlit/TartanShifting"
{
// offsets UVs to make alternating thick and thin stripes
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		_Threshold("Threshold", Range(0, 1)) = 0.2
	}
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 100

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			
			#include "UnityCG.cginc"

			struct appdata
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				float4 vertex : SV_POSITION;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			float4 _MainTex_TexelSize;
			float _Threshold;
			
			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
				fixed2 uvs = i.uv*_MainTex_TexelSize.zw/2; //scale it up
				fixed2 offset = fmod(uvs/2,1)>(1-_Threshold/2);
				uvs = floor(floor(uvs) + offset)+0.5;
				uvs = uvs / (_MainTex_TexelSize.zw); //scale it down
				fixed4 col = tex2D(_MainTex, uvs);
				return col;
			}
			ENDCG
		}
	}
}