I have built a small generator in python that can be used to generate an OSCAD file. The file mainly consists of a syntax tree of OSCAD statements. This way I can transform my own geometry elements to OSCAD reasonably comfortably.
A short list of the elements:
Points
Lines
Polygons
Extrusions
svg path elements
Surfaces in space
affine mappings
Colors (with strong restrictions)
The interactive OSCAD viewer program can then be used to view the model.