Hello, I am an astronomy graduate student at Columbia University, and am trying to use YT to create a 3D visualization of GADGET simulations. Matt Turk suggested I send an email to this list while he is traveling. I have seen that the source code for visualizing GADGET data is in yt/frontends/sph/data_structures.py, but am not sure how to access/use this? I have looked at: http://nbviewer.ipython.org/url/hub.yt-project.org/notebooks/e209c55b6aaa4a9... and http://yt-project.org/doc/visualizing/volume_rendering.html#generating-a-hom... but remain unsure of where to find the relevant source code/what I do with it after I find it. Matt explained that yt/frontends/sph/data_structures.py is "where the data frontend is. The broader yt codebase uses that to index and manage the data but it uses generic interfaces on top," and encouraged me to email the list for more information. Where is the relevant code? Also, where does the generic vs. frontend interface distinction appear? Best, Andrew Weis