// Outline shader v1.0

// Author: Bishop Myers

// Last modified: October 7, 2014

Shader "Custom/Outline" {

	Properties {

		_OutlineColor ("Outline Color", Color) = (0,0,0,1)

		_Outline ("Outline width", Range (0.0, 0.03)) = .005

	}

 

CGINCLUDE

#include "UnityCG.cginc"

 

struct appdata {

	float4 vertex : POSITION;

	float3 normal : NORMAL;

};

 

struct v2f {

	float4 pos : POSITION;

	float4 color : COLOR;

};

 

uniform float _Outline;

uniform float4 _OutlineColor;

 

v2f vert(appdata v) {

	// just make a copy of incoming vertex data but scaled according to normal direction

	v2f o;

	o.pos = mul(UNITY_MATRIX_MVP, v.vertex);

 

	float3 norm   = mul ((float3x3)UNITY_MATRIX_IT_MV, v.normal);

	float2 offset = TransformViewToProjection(norm.xy);

 

	o.pos.xy += offset * o.pos.z * _Outline;

	o.color = _OutlineColor;

	return o;

}

ENDCG

 

	SubShader {

		Tags { "Queue" = "Transparent" }

 

		Pass {

			Name "BASE"

			Cull Back

			Blend Zero One

 

			// uncomment this to hide inner details:

			//Offset -8, -8

 

			SetTexture [_OutlineColor] {

				ConstantColor (0,0,0,0)

				Combine constant

			}

		}

 

		// note that a vertex shader is specified here but its using the one above

		Pass {

			Name "OUTLINE"

			Tags { "LightMode" = "Always" }

			Cull Front

 

			// you can choose what kind of blending mode you want for the outline

			//Blend SrcAlpha OneMinusSrcAlpha // Normal

			//Blend One One // Additive

			Blend One OneMinusDstColor // Soft Additive

			//Blend DstColor Zero // Multiplicative

			//Blend DstColor SrcColor // 2x Multiplicative

 

CGPROGRAM

#pragma vertex vert

#pragma fragment frag

 

half4 frag(v2f i) :COLOR {

	return i.color;

}

ENDCG

		}

 

 

	}

 

	Fallback "Diffuse"

}