AlphaPixel recently delivered a Free/Open Source 3D PDF generation/conversion tool for exporting models to the PRC format and embedding them into PDF files.
Based on an OpenSceneGraph Reader/Writer plugin, and open source PRC code taken from the Asymptote the osgdb_prc plugin converts the geometry, material colors and transparency, and in a limited fashion, the per-vertex coloration of models into a PRC file. This file can be embedded into a PDF file using the libHaru toolkit. The final result is a PDF that can be opened in modern versions of Adobe Reader on any platform, where the model can be viewed in 3D and interacted with.
Open Source PRC file format 3D PDF exporter/converter for OSG
