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Precise coordinates of the celestial sphere

Posted: 20.01.2003, 03:28
by Calculus
Is there a way to point the camera to precise coordinates of the celestial sphere (like the lat and long of the goto menu) ?
I can use the center function on a star but this is not very satisfactory if I don't want to point at any star.

Posted: 27.01.2003, 03:24
by Calculus
No one has an idea ?

Posted: 27.01.2003, 03:33
by selden
Well, there's always the "fake planet" approach: create a planet with all of its orientation coordinates set to 0 and with no rotation. I'd expect that if you to to a long,lat relative to its surface and then use the new "lookback" command ( the * key) you'd be looking at the right place on the celestial sphere. I haven't actually tried it, though.

Posted: 27.01.2003, 03:55
by selden
This seems to do the job:

Code: Select all

"radec-planet" "Sol"
{
   Texture "earthgrid.jpg"
   Radius 7000
   CustomOrbit "vsop87-earth"
   RotationPeriod   1e25
   RotationOffset   0.0 # offset at default epoch J2000
   Obliquity        -23.45

   Albedo           1.0
}


If you want to be able to do it visually, you'll need to create an appropriate surface texture with the grid lines you like.

I hope this helps.

Posted: 27.01.2003, 06:02
by chris
Calculus wrote:No one has an idea ?

No ideas right now, but this is something that we'll be fixing in 1.2.6 . . .

--Chris

Posted: 27.01.2003, 14:47
by Calculus
selden wrote:Well, there's always the "fake planet" approach: create a planet with all of its orientation coordinates set to 0 and with no rotation. I'd expect that if you to to a long,lat relative to its surface and then use the new "lookback" command ( the * key) you'd be looking at the right place on the celestial sphere. I haven't actually tried it, though.

Why couldn't I think about the "fake planet" approach. Very usefull indeed.
Thanks

Posted: 27.01.2003, 15:28
by t00fri
Calculus wrote:
selden wrote:Well, there's always the "fake planet" approach: create a planet with all of its orientation coordinates set to 0 and with no rotation. I'd expect that if you to to a long,lat relative to its surface and then use the new "lookback" command ( the * key) you'd be looking at the right place on the celestial sphere. I haven't actually tried it, though.
Why couldn't I think about the "fake planet" approach. Very usefull indeed.
Thanks


Special emphasis in my contributions to the development of Celestia-1.2.6 will be on "easy maneuvering and quantitative displays". This will include in particular possibilities that the observer clamps to all popular coordinate systems, like

Alt-Azimuth, Equatorial, Object Long-Lat, Ecliptical,...

allowing 2 key easy (forward-backward) moving in parallel to the respective
coordinate axes. I have planned much more in this area, like a "locations" database with access via dialogs both on earth and elsewhere, macros for smooth landing on any location of any extended object + "lookback" (sky observer mode), RA, Dec (Alt-Az, lat-long),.../cursor readouts/,
Improved grids with subdivisions and orientation auto-adapting to FoV and to chosen coordinate system...

My highest priority item has been completed and committed yesterday: taking into account /light-time delays/ in a convenient, highly accurate and efficient manner (c.f. => CVS).

Bye Fridger

Posted: 27.01.2003, 15:51
by Calculus
WOW Fridger, this is good news.
Of course, I have a last question: When :D ?

Posted: 27.01.2003, 18:19
by chris
Calculus wrote:WOW Fridger, this is good news.
Of course, I have a last question: When :D ?


"Sometime in February" has been my answer . . . Probably around the middle of the month.

--Chris