Alpha Texture Cutoff shader has aliasing

Right, here is the shader. it uses a transparency map to hide stuff. However, the problem is because it is a cutoff shader it causes aliasing at the edges

Code (csharp):

1. Shader "Transparent/Mask" {
2.  
3.     // by moffatjason.
4.      
5.     Properties
6.      
7.     {
8.     _MainTex ("Base (RGB) Alpha (A)", 2D) = "white" {}
9.     _Cutoff ("Base Alpha cutoff", Range (0,.9)) = .5
10.     }
11.      
12.     SubShader {
13.      
14.     // Render the mask after regular geometry, but before masked geometry and
15.     // transparent things.
16.      
17.     Tags {"Queue" = "Geometry+10"}
18.      
19.     // Don't draw in the RGBA channels; just the depth buffer
20.      
21.     ColorMask 0
22.     ZWrite On
23.      
24.     Pass
25.      
26.     {
27.     AlphaTest LEqual [_Cutoff]
28.     SetTexture [_MainTex] {
29.     combine texture * primary, texture
30.     }
31.      
32.     }
33.      
34.     }
35.  
36. }

1.changing the anti-aliasing in the project quality settings didn't help
2. Adding anti-aliasing as a post processing effect did help, however it blurred everything else as well (since this app is 2d that won't work)

Any ideas on how to remove this anti-alasing

 

If you can, use alpha blending instead and change the alpha texture to have a sharp transition. You don't need to blur it or anything, texture filtering alone will reduce the aliasing.