Plugin or DLL tools

Hello,

I have to externalize my CAD engine (put it outside the main program) to be
able to use it with other program (all made with delphi) also.
For doing this I have two ways :
- creating a DLL (I'm not easy with this kind of thing)
- creating a pluggin

not that I need to access datas (simple or arrays), bitmap, strings etc..

any solutions or tips are welcome.

Thanks

John.


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