Constellation and galactic arms labels

Cham · Post #1by **Cham** » 14.10.2007, 16:36

Just a suggestion for Celestia 1.5.0 :

1- The constellation labels should fade away at some distance. Around 10000 LY from Sol, they draw an ugly and unreadable patch on the screen. They should gradually fade away.

2- Currently, we don't have any galactic arms labels (Orion arm, etc...). It could be great to have them, drawn with their own color. IMO, these labels should have the same font style and size as the constellation labels (only a different color, and some transparency effect).

Hungry4info · Post #2by **Hungry4info** » 14.10.2007, 16:49

That's not a bad idea. If the constellation labels fade away before the arm labels appear, then there won't be the problem of confusing the two.

Cham · Post #3by **Cham** » 14.10.2007, 17:03

In the case of the constellation labels, I'm trying to add this code in "render.cpp" :

Code: Select all

case Renderer::ConstellationLabels:
            labelColor = Renderer::ConstellationLabelColor;
            appMagEff = astro::absToAppMag(-7.5f, (float) distanceToSun);
            step = 6.0f;
            break;

The arbitrary values 7.5 and 6.0 will have to be adjusted to get a nice fading with distance. My only difficulty for now is the distanceToSun which isn't right. I just need to get the proper distance of the observer from Sol. The label fading should start at approximatively 10000 LY from Sol.

Post #4by **ElChristou** » 14.10.2007, 17:46

Cham wrote:...The label fading should start at approximatively 10000 LY from Sol.

I think the fading should begin much before, at ~500ly because at this distance the labels already lose completely their purpose... They could be completely transparent at ~0.7Kpc...

Cham · Post #5by **Cham** » 14.10.2007, 17:53

ElChristou wrote:I think the fading should begin much before, at ~500ly because at this distance the labels already lose completely their purpose... They could be completely transparent at ~0.7Kpc...

I don't agree. I think it's still interesting to see "how much" the constellations are losing their meaning with distance (while watching the constellation lines deformation with distance). 500 LY is too short, IMO. Should start fading at, at the very least, 1000 LY. We still need to identify the constellation at this distance.

Post #6by **ElChristou** » 14.10.2007, 18:02

Possible, it's just that your initial 10000ly seems a bit too much to me...

Cham · Post #7by **Cham** » 14.10.2007, 18:04

ElChristou wrote:Possible, it's just that your initial 10000ly seems a bit too much to me...

I may agree on this. The value can be adjusted once the code works.

In my case, I'm just a monkey typing random characters in the code, with some "educated guesses" ! :lol:

buggs_moran · Post #8by **buggs_moran** » 14.10.2007, 23:46

Cham wrote:[In my case, I'm just a monkey typing random characters in the code, with some "educated guesses" !

Keep it up, you should be able to reproduce the US Library of Congress...or at least a sonnet :wink:

http://en.wikipedia.org/wiki/Infinite_monkey_theorem

MKruer · Post #9by **MKruer** » 15.10.2007, 00:48

Cham wrote:
ElChristou wrote:Possible, it's just that your initial 10000ly seems a bit too much to me...

I may agree on this. The value can be adjusted once the code works.

In my case, I'm just a monkey typing random characters in the code, with some "educated guesses" !

Awe crap. If thats the case, then i guess all the stars in all the universe will have died via heat death before the next release. :twisted: