Celestia Forums

I want to do something very much like xplanet with its marker (label a point by latitude/longitude) and great arc (lines across the surface of the planet between 2 latitude/longitude points) files, with celestia's frame rate, and, preferably, with celestia's beautiful and real star background. I need to be able to update the marker and great arc files. Compatibility with xplanet's file formats would be convenient. I also want rotation around the Earth's axis.

I can get rotation around the Earth by modifying the demo script, but it's not around the axis, and setting the duration to 0 makes it take no time instead of being infinite like I want.

I saw that in March chris said marker files were high on his to do list and should be ready for the next version, but I don't see anything in the v1.2.4 changelong about them.

Is there a way to do any of this without modifying code ? Is anybody working on any of this ? Do you have any suggestions on how I might impliment any of this ? I haven't even started looking at source yet, and I'm getting suggestions that I work with glglobe instead for simplicity. But I'd really prefer to use Celestia.

Though it will be simple to add, I'm afraid that there's still no support for markers like Xplanets or for great arcs. I've been too busy with other parts of Celestia to get to this . . . I'm curious: why do you need to display great arcs?

As for rotating around Earth's axis, there is a way to do that. If you post your .cel file I can modify it to do what you want.

--Chris

I want to use great arcs for ping times between the two points.

The .cel file I'm using:

{
select { object "Sol/Earth" }
gotolonglat { time 0 distance 3 longitude -122 latitude 47 }
orbit { axis [ 0 1 0 ] rate 10 duration 10000000000 }
}