Ellipse painter for tracks with uncertainty ellipses

[Ben Sherman]

I remember when I used to work at Metron (hi!) that we had some visualizations of tracks that had “uncertainty ellipses” associated with them. However, I can’t find any Glimpse ellipse painter or similar tool for drawing such ellipses on tracks. Is there something available to facilitate this? If not, could someone suggest a convenient way of drawing ellipses? Should I just use the PolygonPainter and manually approximate the ellipse with a polygon?

Any help or quick pointer would be greatly appreciated. Thanks!

Ben

[Brandon Borkholder]

Hi Ben!  Good to hear from you again.

Yes, for everything I've done I always approximate the ellipse with a number of points and create the polygon.  The primary reason is that it's straightforward and easy to implement that way.

Another reason that applies to general geometries is that if the ellipse (or any geometry) is geodetic, it's better to project a number of control points into your visual coordinate system (e.g. tangent plane).  Depending on the scale, you can tell a difference.

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[Ben Sherman]

Hi Brandon! Thanks! I really appreciate your help. Great, I will follow through with using the PolygonPainter and approximating the ellipse with a polygon.

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