COM

OpenGL OpenGL: Basic Coding
1

Hi, I know this is not directly related to OpenGL, but I can’t find any other forums that can help me. Can anyone give me a good explanation of COM and the ATL? I’m supposed to learn these things for an ArcGIS API but I have no clue how these things are implemented using C/C++. Can anyone help me and give me links to forums that could help me out some more?

2

Well COM (Component Object Model) is pretty complicated to be discussed in a few lines of text. Microsoft has a link that should help explain what it is and how to use ATL (Active Template Libary) in developing COM components.

Developing COM components in C++ is a real hassle, even with the aid of ATL. If you’re able, you could see about developing them in VB, since that hides all of the messy overblown interfaces.

http://msdn.microsoft.com/library/defaul…com_and_atl.asp

Bode

3

Thanks!

4

This are only structures that point at functions. What is so complicated about them?

BTW, the best language to write COM is Delphi(build-in support for interfaces).

5

This are only structures that point at functions. What is so complicated about them?
BTW, the best language to write COM is Delphi(build-in support for interfaces).

There’s a difference between understanding COM and using COM. Using MFC/VB or any higher level class/object based language allows quick prototyping without knowing the interfaces and IDL involved. But to appreciate the beauty of COM (if that’s possible) is to know how and why it works.

Bode