How to use System.Func<>

I'm using the CoherentNoise library and one of the classes constructors requires "System.Func<int, int, int, float>" I have no idea what to pass it. Intelisense says this:

Code (csharp):

1.  
2. public  VoronoiCells(
3.      int seed
4.      System.Func<int, int, int, float> cellValueSource
5. )
6. Parameter
7. cellValueSource: Function that returns cell's value
8.  
9. Delegate Info
10. TResult Func (T1 arg, T2 arg2, T3 arg3)
11.  
12. Summary
13. Create a new Voronoi diagram using seed. Control points will be obtained
14. using random displacement seed by supplied value

 

System.Func and System.Action are C#'s delegate classes!

Basically, it's asking for a delegate method as an argument, specifically one that takes three integers and returns a float.

There's lots of ways to write these, but the best is using lambda expressions:

Code (CSharp):

1. VeronicCells(1000, (x,y,x) => {
2.  
3.     //do something with x y z and return a float.
4.  
5.     return (float)(x * 2 + y * 5 * z - 1000);
6.  
7. });

Check it out:
http://www.dotnetperls.com/lambda <- Check it out.

That said I'm imagining this library probably already has a number of cellValueSource methods defined somewhere, and is probably expecting you to use one of them.

 

Ok, I kinda understand. But I've tried to implement the lambda and get an error. Here's my code

Code (csharp):

1.  
2. [System.Serializable]
3.         public class Function
4.         {
5.             //Public
6.             [Range(1, 4096)]
7.             public int width = 16;
8.             [Range(1, 4096)]
9.             public int height = 16;
10.  
11.             public float x;
12.             public float y;
13.             public float z;
14.  
15.             public float gain = 1f;
16.             public float bias = 1f;
17.  
18.             public Texture2D ramp;
19.  
20.             public UnityEngine.Texture GetTexture()
21.             {
22.                 CoherentNoise.Generation.Function function = new CoherentNoise.Generation.Function((x, y, z) => {return x + y + z;});
23.  
24.                 Generator gainFunction = function.Gain(gain);
25.                 Generator biasFunction = gainFunction.Bias(bias);
26.  
27.                 if(ramp != null)
28.                     return TextureMaker.RampTexture(width, height, biasFunction, ramp);
29.                 else
30.                     return new UnityEngine.Texture();
31.             }
32.         }
33.  

Here's my error

IndexOutOfRangeException: Array index is out of range.
CoherentNoise.Texturing.TextureMaker+<>c__DisplayClass7.<RampTexture>b__6 (Single x, Single y)
CoherentNoise.Texturing.TextureMaker.Make (Int32 width, Int32 height, System.Func`3 colorFunc, TextureFormat format)
CoherentNoise.Texturing.TextureMaker.RampTexture (Int32 width, Int32 height, CoherentNoise.Generator noise, UnityEngine.Texture2D ramp)
Procedural+Texture+Function.GetTexture () (at Assets/Code/Framework/Procedural.cs:458)
ProceduralTexture.Update () (at Assets/Code/ProceduralTexture.cs:40)