= "\
Qf - partition point to furthest outside facet\n\
Qg - only build good facets (needs 'QGn', 'QVn', or 'PdD')\n\
Qm - only process points that would increase max_outside\n\
Qr - process random outside points instead of furthest ones\n\
Qs - search all points for the initial simplex\n\
Qu - for 'd' or 'v', compute upper hull without point at-infinity\n\
returns furthest-site Delaunay triangulation\n\
Qv - test vertex neighbors for convexity\n\
Qx - exact pre-merges (skips coplanar and angle-coplanar facets)\n\
Qz - add point-at-infinity to Delaunay triangulation\n\
QGn - good facet if visible from point n, -n for not visible\n\
QVn - good facet if it includes point n, -n if not\n\
Q0 - turn off default premerge with 'C-0'/'Qx'\n\
Q1 - sort merges by type instead of angle\n\
Q2 - merge all non-convex at once instead of independent sets\n\
Q3 - do not merge redundant vertices\n\
Q4 - avoid old->new merges\n\
Q5 - do not correct outer planes at end of qhull\n\
Q6 - do not pre-merge concave or coplanar facets\n\
Q7 - depth-first processing instead of breadth-first\n\
Q8 - do not process near-inside points\n\
Q9 - process furthest of furthest points\n\
Q10 - no special processing for narrow distributions\n\
Q11 - copy normals and recompute centrums for tricoplanar facets\n\
Q12 - no error on wide merge due to duplicate ridge\n\
\n\
"