What alternatives there is for openCascade that is free and smaller

Question

Hello all Basically I like to experiment with building 3d modeling application that could Also raytrace the end result , I found only the openCascade lib for such job My question is does it the only alternative for such task ? (im looking for library and not to deal with low level openGL)

Answer 1

I have been using Opencascade for a while, and i am quite impressed with its modelling capabilities. It's performance is okay for objects of simple to medium complexities, but some operations (especially 3d-booleans for objects of medium complexity) take a long time.

Also, several people have reported issues with the memory manager. Worst of all, some of the operations are neither thread safe nor reentrant in the current version.

VTK might be an OSS alternative

Edit 1:

Blender and VTK can be used together, as a little googling showed