Celestia Forums

Well, actually they are rather polished a little than really revised

I took two of Bob's great planet tours (venus and neptune) and did some enhancements that I liked to have. For both tours I invented ambient light dimming, so overall ambient light is zero for lit surface parts, and nonzero for night-side parts - this gives a more 3D-depth look to the whole-planet-views. For the venus tour I also invented cloud layer fading - as every kind of movement in celestia smoothes in and out, it looked a bit wrong if the cloud layer is switched off just like that :snip:

Unfortunately this needs, as addition, a set of increasingly transparent overlay surfaces as cloud layer to work - but it's nice and smooth. Finally I translated the scripts into german and ensured that the text still fits onto a 600x800 display.
-----------------------------------------------------------------------
I'd like to take the chance to plea for

1. a single command ambient light dimming function for cel-scripts.
2. a buildin transparency control function for all kinds of texture layers.
3. a single command transparency fading function for cel-scripts.

in some near future version of celestia.
-----------------------------------------------------------------------
Download the scripts (you'll find them way down on my page) and have fun

maxim


===== Later additions ===============
The Uranus Tour is now also available (See post further down).
.

Sounds cool maxim!

What is the URL for your site?

Don,

Click on his "WWW" button you Moron!

And all this time, I thought you were a genius. Sheesh!

Love ya, Bob

I've been like this for a couple of days now.

Not good.

Howdy maxim,

NICE touches! I really like the ambient light and cloud layer fading / ramping. Gives the view a classy touch.

Congratulations on coming up with these GREAT ideas and demonstrating them too!

The Uranus Tour (original by Bob) is now also available with 'enlightenment' in english and german.

maxim

Maxim,

I too, have enjoyed your modified tours, but I wish to make it clear to you
why I haven't changed them on my end...

The lighting on MY machine presents absolutely NO problems when going
from the night side of Venus to the day side. In fact, it looks rather soothing
to my eyes. Can there be such a discrepency in the lighting on our different
machines? I'm starting to wonder. Now, this DOES present a problem on my
current Tour of Earth script, but this is a different kind of problem. Here,
the night-texture has to be replaced by the day-texture in order to view
some of the items I'd like to display. In these cases, I can't just brighten up
the area, I need to advance time so that the day-texture is displayed.

I'm still curious though... Does anyone else have these darkness problems
when running one of my scripts? Just asking, because - like I said - I
haven't had *any* difficulty in seeing the textures on the night-side of
planets.

As to the fading Venus clouds, I really DO like that feature. The only thing
I wish to do is raise the resolution of the cloud textures so that we can
work from a set of 1k cloud maps, rather than your 512-byte images.

Don't get me wrong here... The work you have done is beautiful, and please
feel free to modify/change anything you like.

Take care, Bob

Nice!
Bob Hegwood's tours are very interesting, and I like that cloud fading effect.
It would be good to see this applied to Earth's polar caps seasonal variation.

Bob Hegwood wrote:Can there be such a discrepency in the lighting on our different machines? I'm starting to wonder.

Sure there is, depending on how each user sets the brightness, contrast and gamma controls on their monitor. Using my settings as an example ...

I use a contrast enhancing filter on my flat panel, increase gamma quite a bit from "normal" use (how much depends on the time of day), and sometimes increase brightness also. Within Celestia itself, I would normally use None or Low for Ambient Light.

Now, along comes a script that sets Ambient Light to a value higher than Medium, and the sunny side of an object becomes too bright and becomes "washed out" looking. It is now difficult to determine details in the texture. BUT, the night side is plainly visible, at night. When this happens, I usually head for the monitor controls. However, if I reset the Ambient Light level within Celestia, the sunny parts look fine, but the night side is dark again.

Soooo, personally, I think maxim's idea and implementation are something that should definately be considered on a "tour" that involves both the sunny and night sides of an object. Or, as you are doing, changing time so the dark side becomes "naturally" light.

Just one persons observations.

Cheers,

Bob,

During the work on the Venus and Neptune tour I had three different monitors in use on my system, two 19' and one 17'. And I learned that there are BIG differences in monitors. On one of them I could still see the night side of planets well, even with the monitor brightness set to zero. On another one I had to set the brightness to 100 to get a dark but sufficiently well looking picture.

So, even my 'dimming' scripts make settings in such a way that you get a optimal look on MY system. Things may look more grey or dark or too bright on other systems. I think that's an unavoidable problem until we get some gamma correction setting included into celestia (and even then you will have to compute a correct gamma factor for your own monitor).

Concerning the fading cloud textures:
I reduced them to 0.5k in order to make them load faster. As I wasn't shure about slow systems, and as they're displayed for only 70 milliseconds each, I found, that one couldn't really see the reduced resolution. So as you are the one with the slow system - if you find that 1k textures still load and show smooth for you, I can easily change the resolution of the texture package to 1k.

The greater effect is the switch between the real cloud layer and the fading layers that had to be defined as alternate surfaces in order to exchange them subsequently. Here you can always see the jump from the radius of the atmospheres hightness to the radius of the venus surface.

maxim

maxim wrote:During the work on the Venus and Neptune tour I had three different monitors in use on my system, two 19' and one 17'. And I learned that there are BIG differences in monitors.

Just for your information, Maxim... When I ran your modified tour, I was
first presented with a totally BLACK dark side of Venus. Then, the lighting
enhancements you added kicked in, and the display became way *too* bright.

My question is... How do we arrive at a happy medium which works on all
monitors? Methinks it may not be currently possible, and that's why I have
simply left the brightness alone. If a tour is too dark for YOUR machine, can't
you simply change the Ambient Light setting I've provided in the script?

Concerning the fading cloud textures:
I reduced them to 0.5k in order to make them load faster. As I wasn't shure about slow systems, and as they're displayed for only 70 milliseconds each, I found, that one couldn't really see the reduced resolution. So as you are the one with the slow system - if you find that 1k textures still load and show smooth for you, I can easily change the resolution of the texture package to 1k.

The problem I have with the cloud-fading is that they go away TOO fast. Maybe
larger textures are what's needed here. If you have them, I'd love to try it
on my "Slow" machine to see what happens.

At any rate, like I said before... Please feel free to do whatever you wish to
the scripts. I just like creating them.

Take care, Bob

Okay, what I don't understand about all of this is why it has to be sooo
complicated. Can't each user simply change the ambient light setting so that
a Tour looks okay on his or her machine? Why do we need all this high-tech
coding to fix a simple problem? Can someone explain this to me please?

Like I keep saying, when I set the ambient light setting for MY machine in a
script, what's to keep you from changing that setting? Why do we need forced
lighting? I just don't get it.

Take care, Brain-Dead.

Bob Hedgewood wrote:My question is... How do we arrive at a happy medium which works on all
monitors? Methinks it may not be currently possible, and that's why I have
simply left the brightness alone. If a tour is too dark for YOUR machine, can't
you simply change the Ambient Light setting I've provided in the script?

Bob,
I didn't do this light dimming because the tour was too dark for me before ,but because it was too flat and without depth contrast. When you look at a moon or planet in real, parts of it will always be deep black. That's also what makes it look like a 3D sphere that floates in deep sky. Pushing up the ambient light all time makes it look flat and (at least to me) dull. So I changed things in a way that the ambient light is only pushed up when really needed, so it's obvious what the object would really look like, and when it's artifically lighted to show and explain features. It's like switching on and off a spot of a huge spacecraft. This way the views are becoming more impressive (to me). That's all.

Bob Hedgewood wrote:Just for your information, Maxim... When I ran your modified tour, I was
first presented with a totally BLACK dark side of Venus. Then, the lighting
enhancements you added kicked in, and the display became way *too* bright.

I'm always dimming up to 90% full ambient and back to 0%. If this is too bright for you, you may alter the script so that it stops dimming up at perhaps 50%. You just have to take out some lines of code (or put comments in front of them). It would be of course a good thing (and easier), if that function could be capsuled into a single command - I'm still in the hope that the cel-language will be developed further.

Bob Hedgewood wrote:The problem I have with the cloud-fading is that they go away TOO fast. Maybe
larger textures are what's needed here. If you have them, I'd love to try it
on my "Slow" machine to see what happens.

The fading time is controlled by the wait statements between texture switching. Try to raise the value from 0.07 to 0.1 or even 0.2. That should make fading much slower. If you don't see the fading at all, but clouds go off like this :snip:, then the machine fails to load the subsequent textures fast enough - that's what I feared and why I made them so small.

maxim

I didn?t see thunders in Venus nightside.Is this implemented?

Bob Hegwood wrote:Maxim,

I too, have enjoyed your modified tours, but I wish to make it clear to you
why I haven't changed them on my end...

The lighting on MY machine presents absolutely NO problems when going
from the night side of Venus to the day side. In fact, it looks rather soothing
to my eyes. Can there be such a discrepency in the lighting on our different
machines? I'm starting to wonder. Now, this DOES present a problem on my
current Tour of Earth script, but this is a different kind of problem. Here,
the night-texture has to be replaced by the day-texture in order to view
some of the items I'd like to display. In these cases, I can't just brighten up
the area, I need to advance time so that the day-texture is displayed.

I'm still curious though... Does anyone else have these darkness problems
when running one of my scripts? Just asking, because - like I said - I
haven't had *any* difficulty in seeing the textures on the night-side of
planets.

As to the fading Venus clouds, I really DO like that feature. The only thing
I wish to do is raise the resolution of the cloud textures so that we can
work from a set of 1k cloud maps, rather than your 512-byte images.

Don't get me wrong here... The work you have done is beautiful, and please
feel free to modify/change anything you like.

Take care, Bob