Question by unity_51HJ2jkrzmHJdQ · Jan 17, 2018 at 05:17 PM · shader pixel color change

Shader for pixel colour just based on z position

I have to colour each object pixels using just the z position of the pixel. I have found this implementation.

 Shader "Unlit/test"
 {
 Properties {
          [PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}
          _ColorTop ("Top Color", Color) = (1,1,1,1)
          _ColorMid ("Mid Color", Color) = (1,1,1,1)
          _ColorBot ("Bot Color", Color) = (1,1,1,1)
          _Middle ("Middle", Range(0.001, 0.999)) = 1
      }
  
      SubShader {
          Tags {"Queue"="Background"  "IgnoreProjector"="True"}
          LOD 100
  
          ZWrite On
  
          Pass {
          CGPROGRAM
          #pragma vertex vert  
          #pragma fragment frag
          #include "UnityCG.cginc"
  
          fixed4 _ColorTop;
          fixed4 _ColorMid;
          fixed4 _ColorBot;
          float  _Middle;
  
          struct v2f {
              float4 pos : SV_POSITION;
              float4 texcoord : TEXCOORD0;
          };
  
          v2f vert (appdata_full v) {
              v2f o;
              o.pos = UnityObjectToClipPos (v.vertex);
              o.texcoord = v.texcoord;
              return o;
          }
 
          fixed4 frag (v2f i) : COLOR {
             fixed4 c = lerp(_ColorBot, _ColorMid, i.texcoord.y / _Middle) * step(i.texcoord.y, _Middle);
              c += lerp(_ColorMid, _ColorTop, (i.texcoord.z - _Middle) / (1 - _Middle)) * step(_Middle, i.texcoord.y);
              c.a = 1;
              return c;
          }
 
 
          ENDCG
          }
      }
 }

But when the object is not a plane object the result is not what I want. Can you help me please?

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