Thanks Zax, I will work closely with you and Ralph to make sure it meets both of your needs.
One option I have thought of is to return a file stream which would allow you to treat it as a file and work with the code you have. I can also return objects that have the properties you would need as well. My hope is to make it where you guys don't have to do much code alterations to implement it in your applications.
I have the three open source libraries I need for each piece and I'm getting my head wrapped around how each works so I can figure out how to bring them all together. Along with that I'm working on getting more familiar with the PDF, DXF, and SVG file types. Once I have a better understanding of all this, I'll be able to come up with a solution to make it all work.
If you guys don't mind, I'm sure I'll have a few questions along the way and I'd like to bounce ideas off the both of you. If you would wrather, we can discuss the details over PMs.