Plane Tracking a Point Keeps Disappearing

Messing about with Voodoo to track some points, I thought I'd attach a plane to one of them. But it flickers off  at some positions.

The plane's outline is still there, so it's on screen, and the point it's tracking is certainly still there, and it doesn't go behind the image (which is 2D anyway) so I'm stumped.

Anything I should be doing differently?


  • Have you checked this out in perspective view yet? Just curious if that gives you a better view of what's happening. 

  • edited February 2016

    @Aladdin4d in Perspective View everything is there all the time and not moving, because the camera is; and that's just moving perfectly normally from frame to frame.

    If I leave all the other other points there, instead of deleting them (I just did that to tidy up the video) and select them to make them visible, they're there all the time in the Active Camera View. As is the plane's outline; it just goes invisible.

    It's Opacity is 100% and there are no keyframes on it. I literally just parented it to the point, zeroed the origin/position and scaled it to fit OK.

  • @Ady , @SimonKJones I think I've found the issue. Hitfilm does not like an angle of -359.9 degrees.

    Changed it to 0 (close enough for horseshoes) and the plane reappeared and is still in the right place.

  • Now that sounds like a bug :)

  • This is probably due to a coordinate conversion issue, due to Voodoo using a different system to HitFilm. We do various conversions already but this might be a case we haven't examined before.

    Can you share the tracking data (presumably an .ma file?) so that I can pass it along to the devs for them to take a look at?

  • edited February 2016

    @SimonKJones Sure, here's a link to just the script and the plane.

    Looking again: earlier in the  position data, the value -0.0 causes a problem, and -359.9 doesn't.  Clicking on the actual values reveals the extra significant digits that cause the flickering; e.g. -0.0 is really -0.084 , so some of the truncated values shown aren't entirely reliable indicators as to what numbers are problematic.

    Even weirder, setting the angles to 0 on X rotation on some positions doesn't fix it, but resetting the entire row does, which...sets them to 0.

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