Celestia Forums

I always have "Label Planets" on. I like it. I would also like some asteroids always labeled. Ceres, Ida, Chiron, and Quaoar. Maybe some others later...

But right now I can only either have Label Asteroids on, which puts the name of all the asteroids or have Label Asteroids off, which turns them all off. There doesn't seem to be an inbetween.

Is there a way to do that? If not, it could be a suggestion for another version.

Well, I still like my idea

It's good to see labelled objects far away, for example, I look at a section of the sky and see the word "Pluto" so I know Pluto is there even if I can't see it.

It would be nice to look at a section of the sky and see far away the word "Quaoar". I can do it, but if I do it and I turn around and look at the Sun say from Neptune's orbit, then I see a ton of names on top of one another somewhere between Mars and Jupiter.

It's impossible as far as I know to make it so that some asteroids are labeled and not others.

Maybe you could have an option somewhere where we insert objects that should always be labeled no matter what the label option on that type of object is.

Couldn't you simply remove the asteroids you're not interested in from your configuration?

- Hank

Yeah, but that's not very useful is it? Just because I don't want an object labelled, I need to completely remove it from Celestia? And when I want to have it labelled, I need to put in back in Celestia?

Well, it's useful in the sense that it works with the current version of Celestia. Another solution would be to change the class of the objects you're interested in from asteroid to planet. Again, not a general solution, but a workaround that could be used with the current version of Celestia.

As for possible enhancements in future versions of Celestia, a while ago I suggested a general approach to the problem of selective display. It was originally proposed in the context of orbit display, but would apply to labels as well. It was based on introducing the concept of "groups".

A group would be an arbitrary collection of objects. Certain groups would be pre-defined based on object types (e.g. "planets", "moons", asteroids"), but other groups could be defined in .ssc files using a "Groups" attribute which would list the names of groups to which an object belongs. Also, there would be a "Group" construct which would list the names of objects belonging to the group. It would also be possible for the user to create ad hoc groups at run-time by adding selected objects to a user-defined group interactively. It might also be possible to define groups as set combinations (union, intersection, etc.) of existing groups, or based on attribute values (e.g. objects larger than a specified radius), or based on arbitrary scripted conditions (using Lua). I may be getting carried away here, but you get the idea: lots of flexibility in defining groups.

Then, you allow all the display option flags (visibility, labels, markers, orbits, etc.) to be set on a per group basis. In the UI, the edit panel simply includes another control to select the group for which the flags are to be turned on or off. For any given object, if a particular flag is set for at least one group to which the object belongs, then the flag applies to the object.

Thus one could have groups for "Centaurs", "Galilean Moons", "Ten Largest Asteroids", "My Favorite Moons of Saturn", "Retrograde Moons of Jupiter", "NEOs", "KBOs", "Moon Landers", "Failed Mars Probes", or whatever you (or anybody) wants. And you could control the display option flags separately for each group.

In terms of implementation, one approach might be to use bit strings. Each group would be allocated to an index in the bit string. For each object, there would be a bit string indicating which groups the object belongs to, and for each display option flag, there would be a bit string indicating which groups have the flag enabled. So to determine if a flag applies to an object, you just do a bit-wise AND of the bit string for the flag and the bit string for the object. If the result is non-zero, the flag applies. If there aren't too many active groups (up to 64, say?), this might not be too expensive.

Would something like this address your problem?

- Hank

That's a pretty good idea HankR - definitely something to think about for a future version!

Just as a matter of interest... For someone who comes up with all these great ideas- how come you never registered on the board?

As another possible work-around, for the time being, you could use Markers. You can control the size, color and shape of the marker via a simple script, as shown over in the Celestia Scripting forum:
http://shatters.net/forum/viewtopic.php?p=21023

Hope this helps.

Actually, I'm registered as "hank". I'm just too lazy to log in to post. Actually, several times early on my login timed out while I in the middle of composing a post. This caused the username to be lost. I found it was safer to not log in, and always enter the username myself. I believe this situation has since been improved, but old habits are hard to break.

- Hank

As long as there is no other way, removing the asteroids from the program to prevent their names from appearing may be the only way. I won't do it though, because I want them all in the program. I'll just have to live with the asteroids not being labelled.

I haven't looked into Don's idea yet, but I will later thanks.

You suggestion for another version of Celestia Hank is very interesting. I'm sure it would solve my problem and other people's problems too. It would give us much more flexibility. Does anyone who matters read this board? How come our suggestions get no replies? I think they're good.

fred wrote: Does anyone who matters read this board? How come our suggestions get no replies? I think they're good.

It's because the developers are lazy.

--Chris

chris wrote:It's because the developers are lazy.

That must be it!

- Hank (ROTFLMAO)

Err....Who matters? We all do...

Do the developers read this? Yes they do (Chris Laurel is the moderator in this place, I think).

Are they lazy? Start up Celestia, fly around the solar system, go to the farthest star and look back, and you tell me...

I don't know if it's true that everyone matters because I didn't get a response to my original post until after I posted a response to it.

But "anyone who matters" referred to the developers of this program. I was asking if anyone who works on developing this program read this board.

If the suggestions get no comments, we don't know if it's because they're bad or because no one who works on the development of this program has read them.

As for saying that the developers are lazy, I really doubt that to be true but I understand it was said as a joke.

chris wrote:It's because the developers are lazy.

--Chris

Yeah, right. You only work 40-60 hours a week at your "normal" job, then try to live some semblance of a life (family? cleaning house? party?) while working another unknown amount of hours on Celestia.

When do you sleep? What about eating? Oh, that's right, programmers live on Jolt Cola and pizza.

Mmm...Jolt Cola and pizza...heaven on earth

[quote="don]When do you sleep? What about eating? Oh, that's right, programmers live on Jolt Cola and pizza.
[/quote]
No Jolt or pizza for me . . . There's usually just a glass of water by my computer, and occasionally a snifter of calvados to accompany mellow late-night hacking session.

--Chris

I'm a black coffee man, myself...

Besides, my wife says my aura is all wrong if I don't get my caffeine....

Oh the joys of being married to a very patient pagan

Cormoran

(rapidly reaching the point where I'm so buzzed I can't type)

fred wrote:You suggestion for another version of Celestia Hank is very interesting. I'm sure it would solve my problem and other people's problems too. It would give us much more flexibility. Does anyone who matters read this board? How come our suggestions get no replies? I think they're good.

Getting this thread back on topic . . . Hank's suggestion is a very good one, and I think it (or something like it) will be implemented eventually. As you've observed, the sheer number of objects available through add-ons demands a more sophisticated scheme for controlling which ones are shown. The other developers and I do read the suggestions here, and the genesis many (perhaps most) of the features now in Celestia can be traced to some thread in this forum.

--Chris