MattRix · December 12, 2015 19:22 · Dec 12, 2015
diff --git a/EdgeDetectNormals.shader b/EdgeDetectNormals.shader
@@ -0,0 +1,325 @@
+
+Shader "Hidden/EdgeDetect" { 
+	Properties {
+		_MainTex ("Base (RGB)", 2D) = "" {}
+	}
+
+	CGINCLUDE
+
+	#include "UnityCG.cginc"
+
+	struct v2f {
+		float4 pos : SV_POSITION;
+		float2 uv[5] : TEXCOORD0;
+	};
+
+	struct v2fd {
+		float4 pos : SV_POSITION;
+		float2 uv[2] : TEXCOORD0;
+	};
+
+	sampler2D _MainTex;
+	uniform float4 _MainTex_TexelSize;
+
+	sampler2D _CameraDepthNormalsTexture;
+	sampler2D_float _CameraDepthTexture;
+
+	uniform half4 _Sensitivity; 
+	uniform half4 _BgColor;
+	uniform half _BgFade;
+	uniform half _SampleDistance;
+	uniform float _Exponent;
+
+	uniform float _Threshold;
+
+	struct v2flum {
+		float4 pos : SV_POSITION;
+		float2 uv[3] : TEXCOORD0;
+	};
+
+	v2flum vertLum (appdata_img v)
+	{
+		v2flum 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) * _SampleDistance;
+		o.uv[2] = uv + float2(+_MainTex_TexelSize.x, -_MainTex_TexelSize.y) * _SampleDistance;
+		return o;
+	}
+
+
+	fixed4 fragLum (v2flum i) : SV_Target
+	{
+		fixed4 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);
+		len = step(len, _Threshold);
+		//if(len >= _Threshold)
+		//	original.rgb = 0;
+
+		return len * lerp(original, _BgColor, _BgFade);			
+	}	
+
+	inline half CheckSame (half2 centerNormal, float centerDepth, half4 theSample)
+	{
+		// difference in normals
+		// do not bother decoding normals - there's no need here
+		half2 diff = abs(centerNormal - theSample.xy) * _Sensitivity.y;
+		half isSameNormal = (diff.x + diff.y) * _Sensitivity.y < 0.1;
+		// difference in depth
+		float sampleDepth = DecodeFloatRG (theSample.zw);
+		float zdiff = abs(centerDepth-sampleDepth);
+		// scale the required threshold by the distance
+		half isSameDepth = zdiff * _Sensitivity.x < 0.09 * centerDepth;
+
+		// return:
+		// 1 - if normals and depth are similar enough
+		// 0 - otherwise
+
+		return isSameNormal * isSameDepth;
+	}	
+
+	v2f vertRobert( appdata_img v ) 
+	{
+		v2f o;
+		o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
+
+		float2 uv = v.texcoord.xy;
+		o.uv[0] = uv;
+
+		#if UNITY_UV_STARTS_AT_TOP
+		if (_MainTex_TexelSize.y < 0)
+			uv.y = 1-uv.y;
+		#endif
+
+		// calc coord for the X pattern
+		// maybe nicer TODO for the future: 'rotated triangles'
+
+		o.uv[1] = uv + _MainTex_TexelSize.xy * half2(1,1) * _SampleDistance;
+		o.uv[2] = uv + _MainTex_TexelSize.xy * half2(-1,-1) * _SampleDistance;
+		o.uv[3] = uv + _MainTex_TexelSize.xy * half2(-1,1) * _SampleDistance;
+		o.uv[4] = uv + _MainTex_TexelSize.xy * half2(1,-1) * _SampleDistance;
+
+		return o;
+	} 
+
+	v2f vertThin( appdata_img v )
+	{
+		v2f o;
+		o.pos = mul (UNITY_MATRIX_MVP, v.vertex);
+
+		float2 uv = v.texcoord.xy;
+		o.uv[0] = uv;
+
+		#if UNITY_UV_STARTS_AT_TOP
+		if (_MainTex_TexelSize.y < 0)
+			uv.y = 1-uv.y;
+		#endif
+
+		o.uv[1] = uv;
+		o.uv[4] = uv;
+
+		// offsets for two additional samples
+		o.uv[2] = uv + float2(-_MainTex_TexelSize.x, -_MainTex_TexelSize.y) * _SampleDistance;
+		o.uv[3] = uv + float2(+_MainTex_TexelSize.x, -_MainTex_TexelSize.y) * _SampleDistance;
+
+		return o;
+	}	  
+
+	v2fd vertD( appdata_img v )
+	{
+		v2fd o;
+		o.pos = mul (UNITY_MATRIX_MVP, v.vertex);
+
+		float2 uv = v.texcoord.xy;
+		o.uv[0] = uv;
+
+		#if UNITY_UV_STARTS_AT_TOP
+		if (_MainTex_TexelSize.y < 0)
+			uv.y = 1-uv.y;
+		#endif
+
+		o.uv[1] = uv;
+
+		return o;
+	}
+
+	float4 fragDCheap(v2fd i) : SV_Target 
+	{	
+		// inspired by borderlands implementation of popular "sobel filter"
+
+		float centerDepth = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, i.uv[1]));
+		float4 depthsDiag;
+		float4 depthsAxis;
+
+		float2 uvDist = _SampleDistance * _MainTex_TexelSize.xy;
+
+		depthsDiag.x = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist)); // TR
+		depthsDiag.y = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(-1,1))); // TL
+		depthsDiag.z = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(-1,1))); // BR
+		depthsDiag.w = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist)); // BL
+
+		depthsAxis.x = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(0,1))); // T
+		depthsAxis.y = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(1,0))); // L
+		depthsAxis.z = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(1,0))); // R
+		depthsAxis.w = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(0,1))); // B
+
+		depthsDiag -= centerDepth;
+		depthsAxis /= centerDepth;
+
+		const float4 HorizDiagCoeff = float4(1,1,-1,-1);
+		const float4 VertDiagCoeff = float4(-1,1,-1,1);
+		const float4 HorizAxisCoeff = float4(1,0,0,-1);
+		const float4 VertAxisCoeff = float4(0,1,-1,0);
+
+		float4 SobelH = depthsDiag * HorizDiagCoeff + depthsAxis * HorizAxisCoeff;
+		float4 SobelV = depthsDiag * VertDiagCoeff + depthsAxis * VertAxisCoeff;
+
+		float SobelX = dot(SobelH, float4(1,1,1,1));
+		float SobelY = dot(SobelV, float4(1,1,1,1));
+		float Sobel = sqrt(SobelX * SobelX + SobelY * SobelY);
+
+		Sobel = 1.0-pow(saturate(Sobel), _Exponent);
+		return Sobel * lerp(tex2D(_MainTex, i.uv[0].xy), _BgColor, _BgFade);
+	}
+
+	// pretty much also just a sobel filter, except for that edges "outside" the silhouette get discarded
+	//  which makes it compatible with other depth based post fx
+
+	float4 fragD(v2fd i) : SV_Target 
+	{	
+		// inspired by borderlands implementation of popular "sobel filter"
+
+		float centerDepth = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, i.uv[1]));
+		float4 depthsDiag;
+		float4 depthsAxis;
+
+		float2 uvDist = _SampleDistance * _MainTex_TexelSize.xy;
+
+		depthsDiag.x = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist)); // TR
+		depthsDiag.y = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(-1,1))); // TL
+		depthsDiag.z = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(-1,1))); // BR
+		depthsDiag.w = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist)); // BL
+
+		depthsAxis.x = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(0,1))); // T
+		depthsAxis.y = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(1,0))); // L
+		depthsAxis.z = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]+uvDist*float2(1,0))); // R
+		depthsAxis.w = Linear01Depth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv[1]-uvDist*float2(0,1))); // B
+
+		// make it work nicely with depth based image effects such as depth of field:
+		depthsDiag = (depthsDiag > centerDepth.xxxx) ? depthsDiag : centerDepth.xxxx;
+		depthsAxis = (depthsAxis > centerDepth.xxxx) ? depthsAxis : centerDepth.xxxx;
+
+		depthsDiag -= centerDepth;
+		depthsAxis /= centerDepth;
+
+		const float4 HorizDiagCoeff = float4(1,1,-1,-1);
+		const float4 VertDiagCoeff = float4(-1,1,-1,1);
+		const float4 HorizAxisCoeff = float4(1,0,0,-1);
+		const float4 VertAxisCoeff = float4(0,1,-1,0);
+
+		float4 SobelH = depthsDiag * HorizDiagCoeff + depthsAxis * HorizAxisCoeff;
+		float4 SobelV = depthsDiag * VertDiagCoeff + depthsAxis * VertAxisCoeff;
+
+		float SobelX = dot(SobelH, float4(1,1,1,1));
+		float SobelY = dot(SobelV, float4(1,1,1,1));
+		float Sobel = sqrt(SobelX * SobelX + SobelY * SobelY);
+
+		Sobel = 1.0-pow(saturate(Sobel), _Exponent);
+		return Sobel * lerp(tex2D(_MainTex, i.uv[0].xy), _BgColor, _BgFade);
+	}
+
+	half4 fragRobert(v2f i) : SV_Target {				
+		half4 sample1 = tex2D(_CameraDepthNormalsTexture, i.uv[1].xy);
+		half4 sample2 = tex2D(_CameraDepthNormalsTexture, i.uv[2].xy);
+		half4 sample3 = tex2D(_CameraDepthNormalsTexture, i.uv[3].xy);
+		half4 sample4 = tex2D(_CameraDepthNormalsTexture, i.uv[4].xy);
+
+		half edge = 1.0;
+
+		edge *= CheckSame(sample1.xy, DecodeFloatRG(sample1.zw), sample2);
+		edge *= CheckSame(sample3.xy, DecodeFloatRG(sample3.zw), sample4);
+
+		return edge * lerp(tex2D(_MainTex, i.uv[0]), _BgColor, _BgFade);
+	}
+
+	half4 fragThin (v2f i) : SV_Target
+	{
+		half4 original = tex2D(_MainTex, i.uv[0]);
+
+		half4 center = tex2D (_CameraDepthNormalsTexture, i.uv[1]);
+		half4 sample1 = tex2D (_CameraDepthNormalsTexture, i.uv[2]);
+		half4 sample2 = tex2D (_CameraDepthNormalsTexture, i.uv[3]);
+
+		// encoded normal
+		half2 centerNormal = center.xy;
+		// decoded depth
+		float centerDepth = DecodeFloatRG (center.zw);
+
+		half edge = 1.0;
+
+		edge *= CheckSame(centerNormal, centerDepth, sample1);
+		edge *= CheckSame(centerNormal, centerDepth, sample2);
+
+		return edge * lerp(original, _BgColor, _BgFade);
+	}
+
+	ENDCG 
+
+Subshader {
+ Pass {
+	  ZTest Always Cull Off ZWrite Off
+
+      CGPROGRAM
+      #pragma vertex vertThin
+      #pragma fragment fragThin
+      ENDCG
+  }
+ Pass {
+	  ZTest Always Cull Off ZWrite Off
+
+      CGPROGRAM
+      #pragma vertex vertRobert
+      #pragma fragment fragRobert
+      ENDCG
+  }
+ Pass {
+	  ZTest Always Cull Off ZWrite Off
+
+      CGPROGRAM
+	  #pragma target 3.0   
+      #pragma vertex vertD
+      #pragma fragment fragDCheap
+      ENDCG
+  }
+ Pass {
+	  ZTest Always Cull Off ZWrite Off
+
+      CGPROGRAM
+	  #pragma target 3.0   
+      #pragma vertex vertD
+      #pragma fragment fragD
+      ENDCG
+  }
+ Pass {
+	  ZTest Always Cull Off ZWrite Off
+
+      CGPROGRAM
+	  #pragma target 3.0   
+      #pragma vertex vertLum
+      #pragma fragment fragLum
+      ENDCG
+  }
+}
+
+Fallback off
+
+} // shader