Hi Geoffrey,<div><br></div><div>Can you try setting steady_north=True, north_vector=[0,0,1], and not specify a rot_vector in the rotation call?</div><div><br></div><div>Sam<br><br><div class="gmail_quote">On Thu, Sep 13, 2012 at 12:51 PM, Geoffrey So <span dir="ltr"><<a href="mailto:gsiisg@gmail.com" target="_blank">gsiisg@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>Short version:</div><div><br></div><div>The following movie shows what's possible with yt-dev ~2.1</div><div>
The camera rotates about z axis of the data with a constant azimuthal angle w.r.t the z of the data:</div>
<div>curl -O <a href="http://lca.ucsd.edu/~gso/test_movies/Density.avi" target="_blank">http://lca.ucsd.edu/~gso/test_movies/Density.avi</a></div><div><br></div><div>The following movies shows what happens now if I have a rotation vector or no rotation vector</div>
<div><br></div><div>Weird camera rotation:</div><div>curl -O <a href="http://lca.ucsd.edu/~gso/test_movies/with_rot_vector.mpg" target="_blank">http://lca.ucsd.edu/~gso/test_movies/with_rot_vector.mpg</a> </div><div>Camera rotates about the "up" axis of the camera:</div>
<div>curl -O <a href="http://lca.ucsd.edu/~gso/test_movies/no_rot_vector.mpg" target="_blank">http://lca.ucsd.edu/~gso/test_movies/no_rot_vector.mpg</a></div><div><br></div><div>Long version:</div><div><br></div>I brought this issue up a while back but got distracted before it was resolved, and over past two days did more digging/testing.<div>
<br></div><div>symptom:</div><div><br></div><div>I cannot rotate the camera about the z axis of the data while keeping the azimuthal angle constant anymore, where as I could do this before in I believe yt-dev 2.1ish. </div>
<div><br></div><div>What I tried/found:</div><div><br></div><div>I thought I mailed the dev list but couldn't dig it out of the yt-dev archive, so maybe I only complained in IRC before. This thread is the latter portion where Nathan and Sam were helping me with helpful suggestions and what to try.</div>
<div><a href="http://lists.spacepope.org/htdig.cgi/yt-dev-spacepope.org/2012-August/002267.html" target="_blank">http://lists.spacepope.org/htdig.cgi/yt-dev-spacepope.org/2012-August/002267.html</a></div><div>The example script Sam provided (by not specifying the north_vector) will rotate the camera about the camera's z (up) axis, but not the data's z axis, if looking at the image, what I am trying to do is have the camera rotate around the disk about the axis normal to the disk's plane (assume disk is in x-y plane).</div>
<div><br></div><div>I tried playing with the north_vector, steady_north in the camera object, and the rot_vector in cam.rotation, made sure the vectors are normalized.</div><div><br></div><div>I found that if I specify the normal vector (usually designated "L" in example scripts) as the x or -x axis, and the north vector as the z axis, I can look at the data cube (in this case Enzo data), and watch it rotate about the z axis, the behavior I expected. However, if my L is tilted not 90 degrees (non x or y axis), no matter what I specify as the north vector, the rotation angle changes and the cube wobbles or precesses.</div>
<div><br></div><div>I've modified Sam's script to image the entire box, because it's harder to see the effect if we're looking at a sphere</div><div><div><a href="http://paste.yt-project.org/show/2689/" target="_blank">http://paste.yt-project.org/show/2689/</a></div>
</div><div>This script will produce the strange rotation, if the rot_vector is taken out on line 17, then the rotation about the camera up is recovered. But that's not what was done before and not what I wanted.</div>
<div><br></div><div>I also wrote the script to reproduce the effect I wanted with the rotation, but this is a lot more work than before. I have to specify a new L and a new up angle for the camera for every frame to get back the effect I wanted.</div>
<div><div><a href="http://paste.yt-project.org/show/2690/" target="_blank">http://paste.yt-project.org/show/2690/</a></div></div><div><br></div><div>Hope this help track down the problem, cam.rotation is so much simpler to use :-)</div>
<div>
<br></div><div>From</div><span class="HOEnZb"><font color="#888888"><div>G.S.</div>
</font></span><br>_______________________________________________<br>
yt-dev mailing list<br>
<a href="mailto:yt-dev@lists.spacepope.org">yt-dev@lists.spacepope.org</a><br>
<a href="http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org" target="_blank">http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
<br></blockquote></div><br></div>