Marc's solution seems to be the best, but if you really need it in C # (in ASP.NET right?) Then you can consider AJAX, but yes, this is kind of a bad approach.
If these are the winforms you are talking about, I would consider using a 2d graphics engine for this. otherwise your idea MAY work with standard .net formats, it just doesn’t look very beautiful ....
you can take a look at this, it seems like a good starting point for working with directX and C #
http://www.csharp-home.com/index/tiki-print_article.php?articleId=146
Good luck with your project!
Esh