Array passed to ComputeBuffer.SetData(array) must be blittable

Not sure if this is the right board for compute shader related topics..

My question is: can I use a class array to send data to and from a compute buffer?

Like:

Code (CSharp):

1.  public class TestClass
2. {          
3.     public int value;
4. }
5.  
6. ...
7.  
8. public TestClass[] m_Classes;
9.  
10. ...
11.  
12. // this throws: Array passed to ComputeBuffer.SetData(array) must be blittable. TestClass is not blittable because it is not of value type ...
13. myComputeBuffer.SetData(m_Classes);
14.  
15.  

I was hoping that using
[StructLayout(LayoutKind.Sequential)]
and / or something like
[MarshalAs(UnmanagedType.LPArray, SizeConst = ...)]
would allow me to use a class like a struct.

But after seeing this check in
https://github.com/Unity-Technologi...master/Runtime/Export/Unsafe/UnsafeUtility.cs

Code (CSharp):

1.  if (!t.IsValueType)
2.                 return String.Format("{0} is not blittable because it is not of value type ({1})\n", name, t);

It seems Unity just prevents non value types in general.

Could someone provide more insight into this?

 

Old thread but it pops up in Google searches.

The problem above is that you are trying to pass a class type (TestClass) to ComputeBuffer. It should work if you change it to struct instead of class.
The struct also can't contain class fields or other complex types.