title: Are there (free) tools or libraries for 3D WPF objects?
body: <p>I wanted to play around with some 3D controls in WPF, but was mildly surprised to find that there were no primitive solid controls in WPF - I just wanted to plop a few spheres and cubes in a scene, but didn't realize I had to render them using meshes.</p>
  
  <p>Surely someone has created libraries of 3d primitives that can be added to WPF 3D scenes by now.  Are any of these libraries free?</p>
  
  <p>How about modeling tools?  I know there are a few free modeling applications (like Blender), but is there a way to export models from these and include them in a WPF application?</p>
  
  <p>Thanks!</p>