Blueprint Shader

I have a camera that I’m using to generate a top down orthographic view of the world to use as an overview map. What I would like it to look like is just black outlines of all the objects on a white background. I would prefer clean lines as opposed to blured lines found in most outline shaders. I came across this: http://wiki.unity3d.com/index.php?title=Silhouette-Outlined_Diffuse which mostly does what I need, but I wanted to apply the effect “globaly” through the camera and not have to put the shader on each object and I don’t know how I would toggle the effect by camera either. Probably somthing along the of this http://www.thecrosshouse.org/Page%208%20-%20Blueprints/Blueprint-First%20Floor.jpg but without the labels and such.

I am using Unity Pro.

Thanks in advance.

Note that some outlines shaders work on geometry (like your one) which means it has to be applied to every object, others work on screen-space, which means they are automatically applied on every object. So you might want to look for screen-space effect.

Otherwise you can look into replacement shaders (camera property) which allows to replace shader on all objects.

While not a perfect solution it produces an effect close enough to what I was looking for. Using the edge detect effect on the map camera and a modified shader from here: http://answers.unity3d.com/questions/301904/edge-highlighting-shader-with-custom-highlight-col.html I came up with this:

Shader "Custom/Edge Highlight" {
Properties {
	_MainTex ("Base (RGB)", 2D) = "white" {}
	_Treshold ("Treshold", Float) = 0.2
}

SubShader {
	Pass {
		ZTest Always Cull Off ZWrite Off
		Fog { Mode off }

CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma fragmentoption ARB_precision_hint_fastest 
#include "UnityCG.cginc"

uniform sampler2D _MainTex;
uniform float4 _MainTex_TexelSize;
uniform float _Treshold;

struct v2f {
	float4 pos : POSITION;
	float2 uv[3] : TEXCOORD0;
};

v2f vert( appdata_img v )
{
	v2f o;
	o.pos = mul (UNITY_MATRIX_MVP, v.vertex);
	float2 uv = MultiplyUV( UNITY_MATRIX_TEXTURE0, v.texcoord );
	o.uv[0] = uv;
	o.uv[1] = uv + float2(-_MainTex_TexelSize.x, -_MainTex_TexelSize.y);
	o.uv[2] = uv + float2(+_MainTex_TexelSize.x, -_MainTex_TexelSize.y);
	return o;
}


half4 frag (v2f i) : COLOR
{
	half4 original = tex2D(_MainTex, i.uv[0]);

	// a very simple cross gradient filter
	half3 p1 = original.rgb;
	half3 p2 = tex2D( _MainTex, i.uv[1] ).rgb;
	half3 p3 = tex2D( _MainTex, i.uv[2] ).rgb;
	
	half3 diff = p1 * 2 - p2 - p3;
	half len = dot(diff,diff);
	if( len >= _Treshold )
		original.xyzw = half4(0f,0f,0f,1.0f);
	else
		original = half4(1f,1f,1f,1.0f);
		
	return original;
}
ENDCG
	}
}

Fallback off

}

The background is either white, or if it is above the threshold then the pixel is black.