To built a flexible PDF rendering we first needed some basics regarding fonts, images and platform abstraction.
The result is isCWT. It contains all abstraction and implementations needed for rendering PDF that are not related to PDF itself.
Keep in mind that this library is built and used primarily for jPod Renderer, so may be you will miss some features when you use it in another context. But, feel free to contact us for improvements.
More information on the intarsys cwt library you will find here.