[yt-users] overplot ~100,000 points onto a figure

Hi, I want to overlie >100,000 points onto a plot. Using annotate_marker I have no issue with a small number of points, however if I want to plot more than 10,0000 points to overlie, it takes almost an hour to produce that plot. Here is the code I use: for ipar in range(len(xpMpc)): slc.annotate_marker(ds.arr([xpMpc[ipar],ypMpc[ipar],zpMpc[ipar]],'Mpc').in_units('code_length'),coord_system='data',marker='.',plot_args={'color':'cyan','s':1,'alpha':0.3}) I wonder is there any way I can speed this up? Thank you very much, Huanqing