Suggestion
ObjectARX and .NET applications
The input point API is powerful and complex, and it deserves special attention if your ObjectARX application wants to use it.
The callback members AcEdInputPointMonitor::monitorInputPoint() and AcEdInputPointFilter::processInputPoint() are invoked on every digitizer event that AutoCAD processes. Be careful about the amount of processing you perform during these callbacks. Other monitors or filters may also be present. Consider doing the following in your applications that use these powerful features: