com.unity.perception/com.unity.perception/Runtime/GroundTruth/Resources/InstanceSegmentation.shader

Shader "Perception/InstanceSegmentation"
{
    Properties
    {
        [PerObjectData] _SegmentationId("Segmentation ID", int) = 0
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            Tags { "LightMode" = "SRP" }

            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            #include "UnityCG.cginc"
            #include "Packing.hlsl"

            struct appdata
            {
                float4 vertex : POSITION;
            };

            struct v2f
            {
                float4 vertex : SV_POSITION;
            };

            uint _SegmentationId;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                return fixed4(
                    UnpackUIntToFloat((uint)_SegmentationId,  0, 8),
                    UnpackUIntToFloat((uint)_SegmentationId,  8, 8),
                    UnpackUIntToFloat((uint)_SegmentationId, 16, 8),
                    UnpackUIntToFloat((uint)_SegmentationId, 24, 8)
                );
            }
            ENDCG
        }
    }
}