INFO: ds9 marker parameters

[eteq]

This is part of a larger effort to collect what parameters do different backends take for markers. For ds9 the concept of "markers" is not cleanly separated from "regions" - in ds9 they are the same thing. But it's still useful to highlight the regions that are actually "marker-like". The authoritative source I think is actually in the ds9 docs for what ever version you're running, but I think http://ds9.si.edu/doc/ref/region.html is the most authoritative online reference.

The main regions most relevant for markers in my experience are point, circle, and ellipse. The format for the region file for those are below:

point x y # point=[circle|box|diamond|cross|x|arrow|boxcircle] [size]
circle x y radius # fill=[0|1]
ellipse x y radius radius angle# fill=[0|1]

each of those can take a much longer list of properties that are listed at http://ds9.si.edu/doc/ref/region.html#RegionProperties I think the most relevant ones for markers, though, are color, width, text, font.

That pretty much covers it, although with the caveat that any arbitrary sort of region might be used as a "marker" - e.g. a weird star-shaped polygon could be used as a "star" marker.

[eteq]

oh, it also supports line styles via dash/dashlist keywords