Celestia Forums

I have been playing around here and there and found a way to move the auroras from my Earth nightligts texture to above the clouds. There are some limitations and I have yet to figure out how to togle them on and off without effecting the clouds. But I am sure I will think of something. Here are some pics.







And this shot shows one of the limitations of this way of doing it.



Any comments are welcom.

Don. Edwards

Hi Don
I am very interested in this. I have been looking for Northern Lights to project onto my fulldome screen, but they are all very low resolution videos. This looks very promising
Regards
Terry Renner

I've been thinking on this too Don. I was going to create a mesh torus above the poles and map a png which would only be visible on the night side by rotating the mesh with the Earth... (by the way, love the new textures) That way, you would see height of the aurorae. Main problem with this of course is the same as yours. Aurorae are visible while the pole is in sunlight. Too bad we can't have seasonal time limits for objects. Start dates and end dates are great but limiting... Seasonal start and end dates would definitely be helpful with your textures too. Maybe, we could assign night side textures to the mesh? I don't have time to try right now. Maybe later today. Gotta get back outside and pick up leaves while it's warm, and of course gotta observe Mars tonight. So much to do, so little, well, you know...

sorry for the crude drawing over your Earth . Obviously the heights are WAY out of whack. It's just for empasis on the torus.

I think you are going in the right direction. I used Rtovalds th_placeholder.3ds on top of Earth to render the Auroras. Of course you can't have any other textures but the cloud layer. If someone could make a transparent model that can have tranparent textures I also have the means to get cloud bumpmaping done. But unless we can have a totally transparent sphere that can be texured with the same layers as a normal one it will not work. Its the same issue for your torus, if it can be skined with a transparent nightside light than the auroras wouldn't be seen in the daytime.
So if anyone has any ideas about how o build tranparent 3ds. models that can be skinned please let us know. We nned them.

Don.

I dunno if this helps, but I came across this rather fab photo of an aurora taken from space...

http://antwrp.gsfc.nasa.gov/apod/ap051105.html

You have inspired me to make this image of an OA planet with spectacular and famous aurorae;
http://www.orionsarm.com/worlds/Corona.html

the image itself is very much contrast-enhanced, and needed quite a bit of attention, but I did use the old night-lights method to make the image. It does seem a little strange to see the shadows of the clouds above the aurora.

Don. Edwards wrote:I think you are going in the right direction. I used Rtovalds th_placeholder.3ds on top of Earth to render the Auroras. Of course you can't have any other textures but the cloud layer. If someone could make a transparent model that can have tranparent textures I also have the means to get cloud bumpmaping done. But unless we can have a totally transparent sphere that can be texured with the same layers as a normal one it will not work. Its the same issue for your torus, if it can be skined with a transparent nightside light than the auroras wouldn't be seen in the daytime.
So if anyone has any ideas about how o build tranparent 3ds. models that can be skinned please let us know. We nned them.

Don.

OK, verrrrry early work on aurorae has yeilded this... First is ground level. Second from LEO. I will post more as there is progress. Need to work on keeping them on the night side, keeping them bright (but not too bright), and thinning them out.

Further work, subdued color, blue-violet added to base. First from southern Canada (Oh Canada!) Je suis un Americain, mais... those aurorae up there sure are pretty... The altitudes are close, green (oxygen exitement) around 80km to 300km. Not sure if I want to throw in some red or not... Also, I don't know if I should add a solid band along the base. There are so many different aurorae. The ones I have seen from up north looked like these. I am going for generalized aurorae. I have seen red ones at my house in Massachusetts. I know they still need to be subdued more.
http://www.clanmoran.net/temp/aurora03.gif

Very nice! I especially like the ground view.

Sorry wont be any futher work on this from me, I am officialy an inactive member. I have more pressing things going on in my life at this time. Good luck with this buggs_moran, you deserve all the credit from this point on.

Don. Edwards

Don. Edwards wrote:Sorry wont be any futher work on this from me, I am officialy an inactive member. I have more pressing things going on in my life at this time. Good luck with this buggs_moran, you deserve all the credit from this point on.

Don. Edwards

Ah, life and it's infinite ups and downs. Hope all works out and we see you back again in the future..

I copied my post to this thread. I don't know why I didn't post this here rather than openinng a new thread. Sorry.

buggs_moran wrote:Okay, so I think the aurora are at a point where I can issue a beta for people to critique... They have issues, very 2 dimensional, disappear at times, end abruptly, show up regardless of time ,date and season, etc, etc. I tried to get some folding and 3 dimensionality, but the textures didn't look nice, poor blending and so on. The altitudes are pretty close, green aurora start at around 80km and can go a few hundred km high. There is a purple lower aurora and red fade above. I guess these would be an example of a VERY active night. Just unzip the zip file and put the files in your extras directory. It "should" work... http://www.clanmoran.net/temp/aurora.zip

Here is some video of the Earth's aurora from space.

http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17165

I'm not sure how much interest there is currently on this add-on, but I will add my input. It looks pretty neat. Unfortunatly, it seems to have some issues working with jestr's VT earth texture. Whenever I zoom in on the Earth, it seems to freeze. I think what it's doing is loading in all the individual textures, but it's not stopping, it just continues loading them, and my memory usage keeps going up and up. When I remove the aurora add-on, the issue goes away. I'm not sure why the 2 add-ons would interfere with eachother, but they definalty are not working together.