RhinoCommon with native DLLs

[Mightywill]

Hello

I need to integrate a custom renderer which is built as native c++ DLLs into Rhino5
Is there any drawbacks if I decide to use RhinoCommon? First of all, can I use managed C++ to interop with these native DLLs without problems?

We are thinking about it because it’s possible that we will need to support our custom renderer on Mac in the future.

[John_Brock]

Moved to Rhino Developer category

[stevebaer]

I think using RhinoCommon is a great way to go. @andy and @JohnM can help with any rendering SDK questions you may have during the process.

I would recommend NOT using managed C++ though for interop and instead write exported C functions that your C# plug-in can use through pinvokes. We can help with getting that process working smoothly also. Managed C++ does not exist on OSX, so your going to run into problems if you decide to port to Mac in the future. I also have found that having the clean divide between C# and C++ is really helpful for code separation and debugging.

[Mightywill]

Thanks, but our renderer has C++ style export interface and as far as I know it’s almost impossible to use such DLLs with PInvoke in managed C++

[nathanletwory (Nathan 'jesterKing' Letwory)]

You should create a C API for your C++ DLL.

I’m currently in the progress of doing this for Cycles. It is written in C++, I have a C API in a separate DLL for it which I then wrap in C#.

With regards to the API, personally I’d hide render structs and classes behind opaque integer IDs. That makes the wrapping process much easier.

/Nathan

[stevebaer]

@jesterKing

You should create a C API for your C++ DLL

That’s exactly what I was trying to recommend. This is what I do for the RhinoCommon SDK. The Rhino C++ SDK is really C++ (classes and all those non-C type things). There is a wrapper DLL named rhcommon_c which is a large collection of exported C functions which call into the lower level Rhino C++ SDK.

[stevebaer]

Here’s some related posts that you may find helpful

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