NOTE 2/8/05:

These files are copied directly out of the HL2 engine to use as a 
starting point for writing your own vgui based "smoothing" tools for dem files.

If you decide to use this, then my suggestion would be to copy these into a MOD in the client .dll and 
clean up the #include's so that you can get it basically compiling and showing up.  

It should be a "tool" just like the net_graph and other vgui
based tools in the client .dll (use a ConVar to show/hide it maybe?)

The sample source actually contains all of the reading/writing code for dem files which is also in deminfo.cpp.

Note that CDemoFile should be changed to CToolDemoFile.

As I recall, you might have to reimplement a "driving" interface like the one in the main demo UI panel.  I would just implement
it as part of this UI, etc.

If you have any questions or run into major snags, please let me know and I'll try to help out.

Yahn Bernier
yahn@valvesoftware.com