Cube shader

ObjectShader

Shader "Custom/ObjectDiffuseStencil" {
	Properties {
		_Color("Color", Color) = (1,1,1,1)
		_myDiffuse ("Diffuse Texture", 2D) = "white" {}
		_myBump ("Bump Texture", 2D) = "bump" {}
		_mySlider ("Bump Amount", Range(0,10)) = 1

		_SRef("Stencil Ref", Float) = 1
		[Enum(UnityEngine.Rendering.CompareFunction)] _SComp("Stencil Comp", Float) = 8
		[Enum(UnityEngine.Rendering.StencilOp)] _SOp("Stencil Op", Float) = 2
	}

	SubShader {
		Stencil {
			Ref [_SRef]
			Comp [_SComp]
			Pass [SOp]
		}

		CGPROGRAM
		#pragma surface surf Lambert

		sampler2D _myDiffuse;
		sampler2D _myBump;
		half _mySlider;
		float4 _Color;

		struct Input {
			float2 uv_myDiffuse;
			float2 uv_myBump;
		};

		void surf (Input IN, inout SurfaceOutput o) {
			o.Albedo = tex2D(_myDiffuse, IN.uv_myDiffuse).rgb * _Color.rgb;
			o.Normal = UnpackNormal(tex2D(_myBump, IN.uv_myBump));
			o.Normal *= float3(_mySlider, _mySlider, 1);
		}

		ENDCG
	}
	Fallback "Diffuse"
}

ThatCubeShader

Shader "Custom/StencilQuad"{
	Properties {
		_Color ("Main Color", Color) = (1,1,1,1)

		_SRef("Stencil Ref", Float) = 1
		[Enum(UnityEngine.Rendering.CompareFunction)] _SComp("Stencil Comp", Float) = 8
		[Enum(UnityEngine.Rendering.StencilOp)] _SOp("Stencil Op", Float) = 2
	}

	SubShader {
		Tags {"Queue" = "Geometry-1"}

		ZWrite off
		ColorMask 0

		Stencil {
			Ref [_SRef]
			Comp [_SComp]
			Pass [_SOp]
		}

		CGPROGRAM 
		#pragma surface surf Lambert

		sampler2D _myDiffuse;

		struct Input {
			float2 uv_myDiffuse;
		};

		void surf(Input IN, inout SurfaceOutput o) {
			o.Albedo = tex2D(_myDiffuse, IN.uv_myDiffuse).rgb;
		}
		ENDCG
	}
}