Shader wont cast shadows

Unity Engine
, , ,
1

Hey all! I am trying to use a Chroma Key shader I found online. Unfortunately, when I apply it to an object, the shadows are still casting relative to the object.

For example you can see the plane shadow behind the object, despite removing the green screen shot:

image
image737×663 90.2 KB

Here is the shader I am using:


Shader "Custom/ChromaKeyShader" {
 		Properties {
                _MainTex ("Base (RGB)", 2D) = "white" {}
                _MaskCol ("Mask Color", Color)  = (1.0, 0.0, 0.0, 1.0)
                _Sensitivity ("Threshold Sensitivity", Range(0,1)) = 0.5
                _Smooth ("Smoothing", Range(0,1)) = 0.5
        }
        SubShader {
                Tags { "Queue"="Transparent"  "RenderType"="Transparent"}
                LOD 100
                

                CGPROGRAM
                #pragma surface surf Lambert alpha addshadow 
 


 				struct Input {
                    float2 uv_MainTex;
                };
 
                sampler2D _MainTex;
                float4 _MaskCol;
                float _Sensitivity;
 				float _Smooth;
 
                void surf (Input IN, inout SurfaceOutput o) {
                        half4 c = tex2D (_MainTex, IN.uv_MainTex);
  
                        float maskY = 0.2989 * _MaskCol.r + 0.5866 * _MaskCol.g + 0.1145 * _MaskCol.b;
						float maskCr = 0.7132 * (_MaskCol.r - maskY);
 						float maskCb = 0.5647 * (_MaskCol.b - maskY);
 
						float Y = 0.2989 * c.r + 0.5866 * c.g + 0.1145 * c.b;
 						float Cr = 0.7132 * (c.r - Y);
 						float Cb = 0.5647 * (c.b - Y);
 
 						float blendValue = smoothstep(_Sensitivity, _Sensitivity + _Smooth, distance(float2(Cr, Cb), float2(maskCr, maskCb)));
						o.Alpha = 1.0 * blendValue;
						o.Emission = c.rgb * blendValue;     

                }

                ENDCG
      
                 
        }
        FallBack "Diffuse"	
}

Let me know what I am doing wrong.