RGBA texture channels and drive world space UV coordinates

I'd like to use the 4 channels of a RGBA textures and mapping every channel in world space distribuiting the channel one after another one like the image below



Is it something possible to do?

Thanks in advance

 

Yep.











You're probably asking about how to do it too.

There are several threads on world space UVs which you can look up on your own, which is the first part of this. The "hard" part is how to handle switching between channels. Really all you need is to calculate something like a checkerboard in the UVs, offset for each channel, and multiply each texture channel by the offset checkerboard mask.

Here's a very basic example:

Code (CSharp):

1. Shader "Unlit/ColorChannelCheckers"
2. {
3.     Properties
4.     {
5.         _MainTex ("Texture", 2D) = "white" {}
6.         _ColorR ("Color R", Color) = (1,0,0,1)
7.         _ColorG ("Color G", Color) = (0,1,0,1)
8.         _ColorB ("Color B", Color) = (0,0,1,1)
9.         _ColorA ("Color A", Color) = (0.5,0.5,0.5,1)
10.     }
11.     SubShader
12.     {
13.         Tags { "RenderType"="Opaque" }
14.         LOD 100
15.  
16.         Pass
17.         {
18.             CGPROGRAM
19.             #pragma vertex vert
20.             #pragma fragment frag
21.             // make fog work
22.             #pragma multi_compile_fog
23.            
24.             #include "UnityCG.cginc"
25.  
26.             struct appdata
27.             {
28.                 float4 vertex : POSITION;
29.                 float2 uv : TEXCOORD0;
30.             };
31.  
32.             struct v2f
33.             {
34.                 float2 uv : TEXCOORD0;
35.                 UNITY_FOG_COORDS(1)
36.                 float4 vertex : SV_POSITION;
37.             };
38.  
39.             sampler2D _MainTex;
40.             float4 _MainTex_ST;
41.            
42.             v2f vert (appdata v)
43.             {
44.                 v2f o;
45.                 o.vertex = UnityObjectToClipPos(v.vertex);
46.                 o.uv = TRANSFORM_TEX(v.uv, _MainTex);
47.                 UNITY_TRANSFER_FOG(o,o.vertex);
48.                 return o;
49.             }
50.  
51.             fixed4 _ColorR, _ColorG, _ColorB, _ColorA;
52.            
53.             fixed4 frag (v2f i) : SV_Target
54.             {
55.                 float2 uvScaled = i.uv.xy * 0.5;
56.                 fixed2 lines = fixed2(step(0.5, frac(uvScaled.x)), step(0.5, frac(uvScaled.y)));
57.  
58.                 fixed maskA = lines.x * lines.y;
59.                 fixed maskB = lines.x * (1-lines.y);
60.                 fixed maskG = (1-lines.x) * lines.y;
61.                 fixed maskR = (1-lines.x) * (1-lines.y);
62.  
63.                 fixed4 mask = fixed4(maskR, maskG, maskB, maskA);
64.  
65.                 fixed4 tex = tex2D(_MainTex, i.uv) * mask;
66.  
67.                 fixed4 col = tex.r * _ColorR +
68.                              tex.g * _ColorG +
69.                              tex.b * _ColorB +
70.                              tex.a * _ColorA;
71.  
72.                 UNITY_APPLY_FOG(i.fogCoord, col);
73.                 return col;
74.             }
75.             ENDCG
76.         }
77.     }
78. }

 

Thank you @bgolus

I'll study what you proposed. Meanwhile thank you very much.

 

I've tried your shader and it's seems a really good start to make what I'd like.
Thank you again.

Now I hope to complete it as I want. This is up to me.

 

I did it!!
Thank you bgolus for your suggestions.

I share what I've achieved to say "thank you" to you and to the community that help me to increase my knowledge.