1.3.1 prerelease

[chris]

I built a 1.3.1 prerelease for Windows:

http://www.shatters.net/celestia/files/celestia-win32-1.3.1pre3.exe

This version has the normal map fixes, new atmosphere code, light time tweaks, and Christophe's recently added object name completion.

Here's a more complete list of changes:

Code: Select all

* Improved inclusion of light travel delay, also in KDE time setting dialog
* Fixed lookback command for subsequent changes of target speed
* Allow wildcard character * inplace of extension for texture filenames
* Fix bump mapping (again)
* Use standard normal maps instead of x-reversed ones
* Compute the radii of stars more accurately by using bolometric magnitudes
* Permit star names to be defined within .stc files
* Fixed near clipping of small deep sky objects
* Windows: added auto magnitude toggle to render menu
* KDE: added popup error notifications
* Allow oblate planets to have atmospheres
* Corrected specular highlights; abrupt cutoff near terminator eliminated
* Fixed 'hole in the sky' bug
* Allow sunset color to be specified in .ssc files
* Bound Ctrl+P to mark/unmark selection
* Implemented tab completion of star, planet, and deep sky object names


(I may have missed a couple . . .)

As usual, Linux users should rely on compiling from the CVS tree to get the latest Celestia changes.

--Chris

[jrobert]

Umm, File not found...

[praesepe]

True... looks like there's a typho, try this link:

http://www.celestiaproject.net/celestia/files/ ... .1pre3.exe

[selden]

Chtis,

Thanks!

One addition that didn't get mentioned is extremely important to those of us who like to see their deep space objects properly oriented.

When you've enabled "orientation editing" with Shift-Tilde (shift ~)
Ctrl-Shift Right-Mouse-Button now adjusts the rotational position around the Z axis.

This addition assumes that the Z axis of your model has been adjusted to point toward your viewpoint by using Ctrl-Shift Left-Mouse-Button.

[JackHiggins]

Nice to see that atmosphere bug fixed!

2 comments though-

The automatic name finisher is very handy, but it would be much better if you could finish typing the name in full, if you wanted. Example: for people who can't touch type, they'll have to keep looking up & down to see has the object name been completed. This could be very annoying...

Also, It would be handy if there were smaller update downloads containing only the exe file and anthing else major that's changed, without any textures etc, instead of having to download an 11MB installer every time... That took me 45 mins on a dialup connection

[ElPelado]

1) I still see a hole in the sky when i am on the surface of the Sun and i look up.

2) can someone explain me what exactly what the "travel delay" does? i mean, i was traveling at the speed of light, and also at 10 c, and i didnt see any change in the time. what should i see??

3)how we define the name of a star in the .stc file??

4)i still have the ctrl+ins problem, so maybe is my computer. i have windows 98 se, but in a few days, i hope, i will get the windows XP, so maybe it will change something.

[t00fri]

...
2) can someone explain me what exactly what the "travel delay" does? i mean, i was traveling at the speed of light, and also at 10 c, and i didnt see any change in the time. what should i see??

ElPelado:

this is a feature that is mainly for people who are interested in the simulation of /precision/ events with Celestia. Like eclipsing moons or the events among Charon and Pluto that I duscussed in another thread.

Such events are often of short duration and located far away such that the light on which our observations are based takes hours to arrive at the observer's location.

We thus have to account for the light-travel delay time (LT) if we want to reproduce such events e.g. from the tabulated timings. Suppose you observe a Charon-Pluto eclipse at time T here on earth with the HST, it actually took place more than 4 hours earlier on Pluto! So we must enter an earlier simulation time into Celestia than the observation time on Earth. This is what the '-' key does for you. The '?' key simply displays the time that light needs to travel from the current location of the /observer/ to the location of the current /selection/.

Ubnfortunately, the LT-delay scheme that I have incorporated so far is still a compromise to some extent for reasons of saving computer power. So the LT should be used with common sense...

Bye Fridger

[billybob884]

An idea for the next release, maybe allow orbit and label colors to be changed. Seems simple enough, to me, anyway.

[ElPelado]

Fridger: i understand, but what i dont understand is how to use the "-" command. when i should turn it on?
if i am watching an object that his light reach me in 4 hs and i activate the LT, i will see what is happening there 4 hs late??

[Christophe]

About object name completion, automatic completion will be disabled in 1.3.1 final, you will have to press TAB even if there is only one possible object name.

You can navigate the list of possible completions using TAB and BACKTAB. Completion works with paths as well, for example try entering sol/

[ElPelado]

i understand about the LT feature, but why it does not work with stars?? because they dont move??

[Don. Edwards]

I have to agree with Jack Higgins about the Celestia updates. To help save some bandwidth it would be a good idea to split Celestia into two separate downloads. A full version and say a "Celestia Lite" which would contain only those files that have been changed or need updating. I think its kind of silly having us constantly download the whole 11meg file when we may only really need 1 or maybe a 2meg download. Remember it would save alot of bandwidth on the site if we all were not downloading 11meg files. Just I though for the next release.

Don.

P.S.
If this sounds a little rough I just woke up and am seeing through blurry allergy eyes

[t00fri]

Fridger: i understand, but what i dont understand is how to use the "-" command. when i should turn it on?
if i am watching an object that his light reach me in 4 hs and i activate the LT, i will see what is happening there 4 hs late??

Once I'll find a little time, I shall write a step by step instuction with a few explicit examples.

Here is a very quick exercise:

Let us place the observer close to Earth, activate 'Follow Earth' and then hit 5 to select Jupiter. Hit c to center Juppi. Then hit '?' which will tell you that the light takes more than 48 minutes from Jupiter to Earth at this moment! Nice to know...

The point is that after switching LT=ON ('-' key), the time display remains the same but the simulation is calculated at an /earlier/ time corresponding to the time the light needs to travel from the selected body to the observer (about 48 mins earlier).

Now you may hit GoTo (G), whence you travel ~instantaneously like a 'superman through hyperspace' to the selected body (Jupiter). You will notice that the time is quickly advancing to the earlier time corresponding to the event time at the /selected body/ (~48 mins earlier). Toggling now '-' will again make no difference as explained by hitting '?': The light travel time between the observer and the selection is now ZERO;-).

NOTE also:

If the target speed exceeds 0.99 c, the LT delay is switched off automatically for reasons of accuracy. As soon as the target speed falls again below 0.99 c, LT is automatically switched on again (c=speed of light).

LT delay is also switched off or becomes inactive, if the selection is not a solar body. This has good reasons;-)
It also explains why it does not work for stars...

Bye Fridger

[JackHiggins]

Another idea for the next version:
A new class of object, "Lander" would be a nice addition, with the upcoming Beagle 2, MER-A and MER-B landings, and the large number of lander addons there are already!

[marc]

A lander class would be great.

Is there a unix library available that would give tcsh shell like behaviour?
ie tab completion, command history and proper insertion and deletion of characters.
This would be very useful for my SQL console.

[chris]

Another idea for the next version:
A new class of object, "Lander" would be a nice addition, with the upcoming Beagle 2, MER-A and MER-B landings, and the large number of lander addons there are already!

Any good reason to distinguish between landers and spacecraft? I am working on a way to make it easy to place objects at fixed locations on the surfaces of planets, but a new class isn't involved.

--Chris

[marc]

I was thinking that the rendering might be different.

[Christophe]

A lander class would be great.

Is there a unix library available that would give tcsh shell like behaviour?
ie tab completion, command history and proper insertion and deletion of characters.
This would be very useful for my SQL console.

For shell like line editing you should look at the GNU readline library.

[marc]

thanks Christophe. Just what i wanted. Will have a good look at this later.

[selden]

* Allow wildcard character * inplace of extension for texture filenames

I was delighted to discover that this works for textures specified within 3DS models as well as for textures declared in .SSC files. This is a big help for those working on Nebula models. It'll save a lot of time when switching back and forth between opaque and transparent surface textures.

Thanks!