[yt-users] volume rendering

[Renyue Cen]

Hi folks,

Some time ago John Wise kindly gave me a yt script that uses AMRKDTree to speed up "camera" 3-d 
rendering, it worked very well and fast (takes like a few minutes to do a rendering of a galaxy with 2048x2048 pixel). 
It looks like

volume = AMRKDTree(pf,   le=le,   re=re,  fields=["Density"],   no_ghost=False)

then used in 
cam = pf.h.camera(c, L, W, (N,N), tf, volume=volume, no_ghost=False, north_vector=Ldm,steady_north=True)

It appears that yt has evolved and the "volume ..." statement no longer works. 
Is there a solution to that in the newer version?

Alternatively, is there another speedy way to do 3-d rendering?

Thanks very much,
Renyue