Weighted Offsets in C#

[nsmela]

Hey all,

Looking to implement a mesh offset that affects points on a mesh differently in a dotnet project. My understanding is that we'd need to use MRWeightedPointsShell for this. I can't find it in C#, just a python example. Please elt me know if I have this correct:

• MRDotNet only references MRMeshC, so files would need to be added to MRMeshC despite MRVoxels having the class needed
• we might be able to copy the MRWeightedPointsShell header and cpp file from MRVoxels to MRMeshC and make small corrections to expose the feature to C
• once that builds successfully, then we can reference it in the MRDotNet project

Is this the right path?

[Grantim]

Hello!

In general yes, while we have fully automated python bindings, C and C# still requires manual updates. So to expose new function to C# we first need to expose it to C layer, and only then we can expose it to C#.

MRMeshC is already has MRVoxels connection, so there is no need to copy files, just create C API functions to call C++ one in MRMeshC.

---

We are now developing automated C bindings, so hopefully soon it will not be an issue.

[nsmela]

Thanks. Are there any examples of using the callback on c sharp side?

[Grantim]

Now we bind callbacks to c# as IntPtr (so it have correct memory alignment inside struct), but I am not sure that this way allows to pass functions from C#.

[nsmela]

Would something like work?

[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
public delegate void MyDelegate(IntPtr value); 

ref: https://manski.net/articles/csharp-dotnet/pinvoke-tutorial/part-3--passing-parameters#marshalling-delegates

My c++ is extremely rusty and I'm worried I'll create more problems than solve if I try this on my own.

[Grantim]

It seems that it should, we will try it, thanks for great suggestion!

---

Unfortunately, now we are concentrated on automating C bindings. we will definitely put this in our roadmap, but not sure how soon we will manage to try it out.

[nsmela]

ok, might be wasting my time by converting the classes to c # then. I'll keep an eye on the repo for when it's implemented, unless you have something else I could help with.