Create auto-stereogram images
Render every mesh depth map with Blender, then generate its stereogram using
the floor_z value from the mesh's JSON sidecar:
for config in test/meshes/*.json; do
blender --background --python test/render_mesh_depth.py -- "$config"
doneGenerated depth masks are written to test/output/masks/, and stereograms
are written to test/output/stereograms/.