[yt-users] Ray casting in simple volume rendering

[Nicholas Earl]

This all sounds exciting, and I'm definitely making headway in terms of
progress on the screen, but I keep getting hung up at a ValueError: shape
mismatch: objects cannot be broadcast to a single shape after this line:

    vcd = grid.get_vertex_centered_data(field).astype('float64')
  File "/Users/earln/yt-i386/src/yt-trunk-svn/yt/lagos/BaseGridType.py",
line 445, in get_vertex_centered_data
    na.add(new_field, cf[1: ,1: ,1: ], new_field)

Not quite sure wherein this would lie. Any possible ideas?

Thanks!
Nick

On Tue, Mar 30, 2010 at 2:20 PM, Matthew Turk <matthewturk at gmail.com> wrote:

> Hi Nicholas,
>
> Yup, the cookbook applies to 1.6, but we've changed things a bit in
> the trunk so as to enable parallel volume rendering -- and to make
> some things nicer.  For instance, you can now sample colormaps,
> automatically add layers, etc etc.  We're also just about ready to
> roll out multivariate volume rendering, including planck functions and
> scattering.
>
> Anyway, I'm sorry that it's not working right now for you!  To use the
> script, we just need to get rid of direct_ray_cast, which we can
> replace with:
>
> vp = pf.h.volume_rendering(L, W, c, Nvec, tf)
> vp.ray_cast()
>
> At this point, we can get the image as vp.image:
>
> to_plot = na.clip(vp.image, vp.image.min(), 0.8 * vp.image.max())
> to_plot = (to_plot - to_plot.min()) / (to_plot.max() - to_plot.min())
>
> (we still have to normalize, unfortunately -- we're working on that
> for the future.)
>
> And we now also provide a saving function:
>
> vr.plot_rgb(to_plot, "%s" % pf)
>
> I've uploaded a new version of the cookbook recipe here:
>
> http://paste.enzotools.org/show/404/
>
> which you can download with "yt_lodgeit.py --download=404".  One thing
> you might consider is that sometimes it's easier to just
> "add_layers(N)" on the transfer function, optionally supplying the
> name of a colormap (defaults to gist_stern) so that yt will add onion
> layers to your image at even intervals.  I've uploaded an example of
> that here:
>
> http://paste.enzotools.org/show/405/
>
> Anyway, sorry for the trouble, but I hope that the annoyance is worth
> the new advantages!
>
> -Matt
>
> On Tue, Mar 30, 2010 at 11:07 AM, Nicholas M. Earl <earlnich at msu.edu>
> wrote:
> > Hey again YT community,
> >
> > I was hoping to get some heading on using the simple volume rending
> script
> > that is written up in the YT cookbook, but it seems that
> direct_ray_casting
> > isn't a part of yt extensions anymore? Is there something to substitute
> > this? I see that in the software sample script, there is a referencing of
> > VolumeRendering, can I use this?
> >
> > Thanks for your time and effort!
> > Nicholas Earl
> > _______________________________________________
> > yt-users mailing list
> > yt-users at lists.spacepope.org
> > http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
> >
> _______________________________________________
> yt-users mailing list
> yt-users at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-users-spacepope.org/attachments/20100331/3b49e615/attachment.htm>