Are there any good arithmetic for calculating texture coordinates of complex model?

I guess youâ€™re looking for some UV-mapper tool, like this one:

http://www.unwrap3d.com/news.aspx

The math behind this is complex and requires various algorithms to be implemented.

Many 3D programs have such tools included, so when you export a model you have texture coordinates ready.

Can I use such tools in my program for calculating the texture coordinates instead of calculating them by myself?