I want to have an input parameter accepting an Int64 value. AddIntegerParameter creates a GH_Integer parameter which is GH_Goo<int>. Is there a way to add Int64 via the API or do I have to make my own GH_Goo<long>?
I think your best option would be to create your own custom GH_Goo<long> class. At the moment, even if you created your own custom type, it wouldn’t be serialized/deserialized correctly with Rhino.Compute. However, we are close (I think) to releasing a new build for Rhino 9 which would open up the possibility of using 3rd party data types like the one your describing. I don’t have an exact date on when that will be released, but I’m hoping it will be soon. We just have some internal testing that needs to occur before it’s released.