Multiple names for solar system objects

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chris
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Re: Multiple names for solar system objects

Post #21by chris » 19.07.2008, 23:47

granthutchison wrote:
chris wrote:I just checked the new code into SVN. If you're not building SVN versions, I'll compile a new binary for you to test with.
Life contains so many learning curves, I never got around to building Celestia for myself. :( So I'd be grateful for the binary, when you can spare the time.

Here you go:
http://www.celestiaproject.net/~claurel/celest ... -r4382.zip

(This isn't quite a 'clean' build of revision 4382, but it should do for testing multiple names.)

--Chris

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Re: Multiple names for solar system objects

Post #22by granthutchison » 20.07.2008, 16:26

Thank you!
Given that this is an extensive revision to the names of many objects, I'm thinking of including a small revision to the style of temporary designator for moons in Celestia. The standard format used by the IAU Minor Planet Centers is of the form "S/1979 J 1", with two spaces. We at present collapse that into "1979J1", and it would seem to be preferable to use the official naming convention as closely as possible.
However, the "/" confuses the parsing of names entered by ENTER:NAME:ENTER, so I think it'll need to be just "1979 J 1", if there are no objections.

The problem with "/" is going to be significant for comet designations, since "C/", "P/", "D/" or "X/" are important components, less dispensible than the "S/" for moons.

Grant

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Re: Multiple names for solar system objects

Post #23by ElChristou » 20.07.2008, 18:16

BTW guys, just a parenthesis, the last build done yesterday still don't show the label of pluto... (the system showing all less the most known dwarf planet... not fantastic... :?)
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Re: Multiple names for solar system objects

Post #24by Cham » 20.07.2008, 18:18

ElChristou wrote:BTW guys, just a parenthesis, the last build done yesterday still don't show the label of pluto... (the system showing all less the most known dwarf planet... not fantastic... :?)

I agree. I already discussed this problem with Chris, some weeks ago. I'm using an small hack, in the solarsys.ssc file to show Pluto-Charon barycenter. Something must be done about this.
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Re: Multiple names for solar system objects

Post #25by BobHegwood » 20.07.2008, 18:38

chris wrote:(This isn't quite a 'clean' build of revision 4382, but it should do for testing multiple names.)
I took advantage of this link and used it to install the 4382 version of Celestia. Looks very nice so far, and I absolutely love the location features. :wink:
Triangles for mountains, circles for craters... Very nice, so thanks for the update.
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Re: Multiple names for solar system objects

Post #26by granthutchison » 20.07.2008, 23:29

granthutchison wrote:The problem with "/" is going to be significant for comet designations, since "C/", "P/", "D/" or "X/" are important components, less dispensible than the "S/" for moons.
This prompts me to wonder about the feasibility and desirability of special parsing for names containing "/". At present Celestia interprets "/" as a delimiter between an object and its satellite, and things therefore go badly wrong if the name of a single object contains a "/".

The number of options requiring special parsing are small, and I think they're unlikely to overlap with true object/satellite situations. We have name strings that begin:

S/ = natural satellite
C/ = nonperiodic comet
X/ = comet with no defined orbit (not likely to appear often in Celestia!)
<integer>P/ = periodic comet
<integer>D/ = periodic comet, now gone (through impact or disintegration)

There's also a category A/, for objects initially identified as comets but reclassified as asteroids. I'm not sure how likely we'd be to use this comet designator in the name list for such an asteroid.

Grant

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Re: Multiple names for solar system objects

Post #27by symaski62 » 21.07.2008, 00:15

:wink:
windows 10 directX 12 version
celestia 1.7.0 64 bits
with a general handicap of 80% and it makes much d' efforts for the community and s' expimer, thank you d' to be understanding.

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chris
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Re: Multiple names for solar system objects

Post #28by chris » 22.07.2008, 19:03

granthutchison wrote:
granthutchison wrote:The problem with "/" is going to be significant for comet designations, since "C/", "P/", "D/" or "X/" are important components, less dispensible than the "S/" for moons.
This prompts me to wonder about the feasibility and desirability of special parsing for names containing "/". At present Celestia interprets "/" as a delimiter between an object and its satellite, and things therefore go badly wrong if the name of a single object contains a "/".

The number of options requiring special parsing are small, and I think they're unlikely to overlap with true object/satellite situations. We have name strings that begin:

S/ = natural satellite
C/ = nonperiodic comet
X/ = comet with no defined orbit (not likely to appear often in Celestia!)
<integer>P/ = periodic comet
<integer>D/ = periodic comet, now gone (through impact or disintegration)

There's also a category A/, for objects initially identified as comets but reclassified as asteroids. I'm not sure how likely we'd be to use this comet designator in the name list for such an asteroid.

I really wish that I'd chosen something other than the forward slash as the delimiter way back in 2001. As it is, I think we're stuck with it.

It should be possible now to define names with forward slashes embedded in them. They should even be displayed correctly as labels and in the overlay text. Enter-selecting these objects with names that contains slashes is a problem however. Although there shouldn't be any overlap with with real names, the ambiguity introduced by names with embedded path delimiter characters makes for some very ugly code. I can also imagine someone creating a moon in an extrasolar system. The full path of such a moon might be "55 Cnc/C/Foo", which looks a lot like a nonperiodic comet name.

I suppose that we could allow an alternate path syntax using the colon as a path delimiter. Celestia would look for an appearance of a colon in the name. If it found one, it would parse the name using a colon as the delimiter and names containing slashes would pose no problem.

--Chris

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Re: Multiple names for solar system objects

Post #29by granthutchison » 22.07.2008, 22:19

chris wrote:It should be possible now to define names with forward slashes embedded in them. They should even be displayed correctly as labels and in the overlay text. Enter-selecting these objects with names that contains slashes is a problem however.
Yes, I was initially encouraged when alternative names contain "S/" appeared without causing some sort of error; but things start to fall apart when trying to enter-select, especially if one attempts to tab across multiple names starting "S/". Since there are always some satellites with only temporary designations, I think I need to avoid using any sort of designation the user can't get at by straight typing. Looks like it's "1979 J 1" for now. For comets, I think I'll provide the catalogue designation as an alternative to the names, and just omit the "/" for now.
At present I've used your suggested ordering for minor planet designators, but made an exception on historical grounds for Pluto, since the simple name has historical priority.

Grant

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Re: Multiple names for solar system objects

Post #30by ElChristou » 23.07.2008, 06:51

Cham wrote:I'm using an small hack, in the solarsys.ssc file to show Pluto-Charon barycenter. Something must be done about this.

Hack or not, as you say something should be done for the default package...
(BTW, sorry for the off topic :oops:)
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Re: Multiple names for solar system objects

Post #31by steffens » 24.07.2008, 08:29

Couldn't we just escape forward slashes as '//' when they are part of a name?
Then a single '/' would be a path separator, but '//' would be interpreted as a literal '/' as a part of a name. This would display as a single '/', of course.

steffens

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Re: Multiple names for solar system objects

Post #32by symaski62 » 24.07.2008, 12:21

hi ! :wink:

entre > P > TAB > entre
windows 10 directX 12 version
celestia 1.7.0 64 bits
with a general handicap of 80% and it makes much d' efforts for the community and s' expimer, thank you d' to be understanding.


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