Empty branches on the tree

[Goonster]

I have just downloaded Frank Gregorio`s superb sun with the solar flares and it works fine . What I did notice is that when you go to Navigation>sol.sys.browser and scroll down to the sun , below it is 5 empty `branches ' on the menu tree . Is this supposed to happen ? I`m sure there used to be the option to re-run the intro but that is no longer there , I might be wrong .

[rthorvald]

I have just downloaded Frank Gregorio`s superb sun with the solar flares and it works fine . What I did notice is that when you go to Navigation>sol.sys.browser and scroll down to the sun , below it is 5 empty `branches ' on the menu tree . Is this supposed to happen ? I`m sure there used to be the option to re-run the intro but that is no longer there , I might be wrong .

That is probably placeholders for the flares, that is entries in the ssc file with blank names. If not labelled like that, each flare would have a name.

- rthorvald

[BobHegwood]

That is probably placeholders for the flares, that is entries in the ssc file with blank names. If not labelled like that, each flare would have a name.

- rthorvald

And can these not be classed as "invisible" in 1.5pre5 and have these
refrences disappear altogether in the browser? Works like that now
on my system. Just FYI.

Thankls, Bob

[Goonster]

I have just downloaded Frank Gregorio`s superb sun with the solar flares and it works fine . What I did notice is that when you go to Navigation>sol.sys.browser and scroll down to the sun , below it is 5 empty `branches ' on the menu tree . Is this supposed to happen ? I`m sure there used to be the option to re-run the intro but that is no longer there , I might be wrong .

That is probably placeholders for the flares, that is entries in the ssc file with blank names. If not labelled like that, each flare would have a name.

- rthorvald

Ah so thats it . Thanks for that .

[rthorvald]

And can these not be classed as "invisible" in 1.5pre5 and have these
refrences disappear altogether in the browser? Works like that now
on my system.

Well, then the flares would have been invisible, too...
We lack an object class that can have invisible names but visible objects.

- rthorvald

[BobHegwood]

And can these not be classed as "invisible" in 1.5pre5 and have these
refrences disappear altogether in the browser? Works like that now
on my system.

Well, then the flares would have been invisible, too...
We lack an object class that can have invisible names but visible objects.

- rthorvald

I'm sorry here... I should re-state this.

There is now an invisible class that does show up in the browser. It
is entirely separated from spacecraft, for example.

I like it.

Thanks, Bob

[rthorvald]

There is now an invisible class that does show up in the browser. It
is entirely separated from spacecraft, for example.

Yes, but you can??t use this class to hold visible objects.

- rthorvald

[BobHegwood]

Yes, but you can??t use this class to hold visible objects.

- rthorvald

Already being used that way... Unless, of course, I'm wrong again.
Previous add-ons which used the invisible class for placeholders, for
example, still work. Or, at least they did. Sorry, but I just wiped my
system clean again, so that I could start on a fresh space to renew
my add-on testing. I could well be wrong again.

Big surprise there...

[rthorvald]

Already being used that way... Unless, of course, I'm wrong again.
Previous add-ons which used the invisible class for placeholders, for
example, still work.

Invisible placeholders use the invisible class. But not visible ones! And the flares needs to be visible, or it won??t be much to look at...

I think you confuse the subjects, here; an invisible placeholder is used if you want a visible object to orbit it. But in this case, the placeholder itself is visible, and if you assign it an invisible class, the actual object (in this case the flares) will become invisible...

In our case here, the placeholder must be VISIBLE since they ARE the flares. At the same time, you don??t want them to have names, so you give them empty SSC names, but use a VISIBLE class (like for example the "moon" or "spacecraft" class).

What we could need, is an invisible class tag that allows visible objects, but invisible object names.

- rthorvald

[selden]

Bob,

Invisible objects are intended to be used as placeholders: you can use them as anchor-points relative to which visible objects can be placed.

However, a problem (as you've already discovered with my Hale Telescope) is that one often needs to place many visible objects relative to that invisible object (although I happened not to use Class "invisible"). Those visible objects often do not need to be individually selectable but they do need their own unique identifiers so that their positions and orientations can be Modified and so that other objects can be placed relative to them.

At the moment there's no way to have a named identifier which does not also show up in Celestia's lists of objects. At one point Chris was hoping to implement names which could be used in catalog files but which would not be listed or selectable by Celestia while it's running, but that hasn't happened yet. In particular, names starting with underscores wouldn't be listed.

I've added a feature request in Tracker on SourceForge to remind him about this

[rthorvald]

Invisible objects are intended to be used as placeholders: you can use them as anchor-points relative to which visible objects can be placed.

Thanks, you managed to describe the problem much better than i...

- rthorvald

[Vincent]

At the moment there's no way to have a named identifier which does not also show up in Celestia's lists of objects.

I've made a change recently in the code so that objects named as the empty string "" don't appear anymore in the Solar System browser... At least in the Windows version. So that should work with 1.5pre5.

[selden]

Vincent,

I trust you are aware that the use of " " as object names is a hack. It's used because a more general solution isn't available -- and only works for "terminal" objects. That is, it only works for objects which don't need to be Modified (oriented using the TwoVector directive, for example) or which don't need to have other objects oriented relative to them.

[BobHegwood]

Well there ya go...

Now everyone can understand their use. here.

Thanks, Runar, Selden... Good stuff.

[Vincent]

That is, it only works for objects which don't need to be Modified (oriented using the TwoVector directive, for example) or which don't need to have other objects oriented relative to them.

Selden,

I didn't realize you were talking about objects that need to be modified.

At one point Chris was hoping to implement names which could be used in catalog files but which would not be listed or selectable by Celestia while it's running, but that hasn't happened yet. In particular, names starting with underscores wouldn't be listed.

That's a good idea. I should have a patch ready quite soon...

[Vincent]

I made some change in the code that prevents objects whose name start with an underscore "_" from being listed in the Windows solar system browser and in the Windows popup menu. Also, these objects become not selectable, and their label and orbit are not drawn anymore.

Here are the modified source files for testing:
http://vincent.gian.club.fr/celestia/_objects.zip

And here's an exe file for Windows users:
http://vincent.gian.club.fr/celestia/_celestia.exe

[BobHegwood]

I made some change in the code that prevents objects whose name start with an underscore "_" from being listed in the Windows solar system browser and in the Windows popup menu. Also, these objects become not selectable, and their label and orbit are not drawn anymore.

Here are the modified source files for testing:
http://vincent.gian.club.fr/celestia/_objects.zip

And here's an exe file for Windows users:
http://vincent.gian.club.fr/celestia/_celestia.exe

Vincent,

Forgive my usual stupidity, but what does the Windows .exe file
represent?

It's much smaller than the normal Windows file, but when I use
it, I get simply the normal Celestia display - with modifications.

Can you tell us what exactly has been modified?

Thanks, Brain-Dead

[Vincent]

Can you tell us what exactly has been modified?

Bob,

The changes are the ones I wrote in my post:

I made some change in the code that prevents objects whose name start with an underscore "_" from being listed in the Windows solar system browser and in the Windows popup menu. Also, these objects become not selectable, and their label and orbit are not drawn anymore.

You can try adding an underscore at the beginning of the name of an object defined in a .ssc file, e.g., change "ISS" into "_ISS". Then, you'll see that:
- _ISS is not listed anymore either in the solar system browser or in the windows popup menu
- The ISS is not selectable anymore, and its label and its orbit are not drawn anymore.

In short, objects whose name starts with an underscore "_" have the same properties as objects of the "Invisible" class, but they're drawn in the rendering scene.

[BobHegwood]

Vincent,

I'm sorry, but perhaps I didn't phrase the question correctly. We lost
13,461 KB from the original Celestia 1.5.Pre5 exe file, so I guess I
was wondering what happened to all of those bytes? I'm simply
assuming that your version is either calling the main program after
a fix, or it's calling everything else it needs independently of the
main program.

Do you understand what I mean? Sorry... I already know I
am Brain-Dead.

[Adirondack]

Bob,

though I didn't check it, I assume that Vincent's _celestia.exe lacks of some additional features (e.g. SPICE support) since this is just a test for invisible entries.

Adirondack