Question How rotate Mask texture in shader?

Hi,
I have this shader (not mine, I can't write shaders). How to rotate only Mask for i.e. 270 degrees?

Code (CSharp):

1. Shader "Unlit/Unmask Shader"
2. {
3.     Properties
4.     {
5.         _MainTex ("Main Texture", 2D) = "" {}
6.         _MaskTex ("Mask Texture", 2D) = "blue" {}
7.         _Width ("Mask Width", Int) = 0
8.         _Height ("Mask Height", Int) = 0
9.         _Threshold ("Threshold", Range(0.0, 1.0)) = 0.9
10.     }
11.  
12.     SubShader
13.     {
14.         Tags { "RenderType"="Transparent" }
15.         LOD 100
16.  
17.         Pass
18.         {
19.             CGPROGRAM
20.             #pragma vertex vert
21.             #pragma fragment frag
22.             // make fog work
23.             #pragma multi_compile_fog
24.  
25.             #include "UnityCG.cginc"
26.  
27.             struct appdata
28.             {
29.                 float4 vertex : POSITION;
30.                 float2 uv : TEXCOORD0;
31.             };
32.  
33.             struct v2f
34.             {
35.                 float2 uv : TEXCOORD0;
36.                 UNITY_FOG_COORDS(1)
37.                 float4 vertex : SV_POSITION;
38.             };
39.  
40.             sampler2D _MainTex;
41.             float4 _MainTex_ST;
42.  
43.             v2f vert (appdata v)
44.             {
45.                 v2f o;
46.                 o.vertex = UnityObjectToClipPos(v.vertex);
47.                 o.uv = TRANSFORM_TEX(v.uv, _MainTex);
48.                 UNITY_TRANSFER_FOG(o,o.vertex);
49.                 return o;
50.             }
51.  
52.             sampler2D _MaskTex;
53.  
54.             int _Width;
55.             int _Height;
56.             float _Threshold;
57.             uniform StructuredBuffer<float> _MaskBuffer;
58.  
59.             fixed4 frag (v2f i) : SV_Target
60.             {
61.                 // sample the texture
62.                 fixed4 mainCol = tex2D(_MainTex, i.uv);
63.                 fixed4 maskCol = tex2D(_MaskTex, i.uv);
64.                 int idx = int(i.uv.y * _Height) * _Width + int(i.uv.x * _Width);
65.                 float mask = _MaskBuffer[idx];
66.                 fixed4 col = lerp(maskCol, lerp(maskCol, mainCol, mask), step(_Threshold, mask));
67.  
68.                 // apply fog
69.                 UNITY_APPLY_FOG(i.fogCoord, col);
70.                 return col;
71.             }
72.             ENDCG
73.         }
74.     }
75. }
76.  

Thank you for help in advance!

 

Hi

It seems the _MaskBuffer is directly sent to the shader from the C# code: wouldn't it be easier to rotate it from there?

Rgds
The3Loutrons

 

But how?

 

Don’t you currently have an C# code that is working with this shader?

 

Yeah, but it only sets a mask
_material.SetTexture("_MaskTex", maskTexture)

What I need is to rotate that Mask texture for 90 or 270 degrees when MainTexture stays as it is.

 

Ok so this is this maskTexture in C# to work on: how is it declared and initialized?

 

It could be declared from code as new Texture or from inspector.