Two cloud layers...

[ElPelado]

Today it was cloudy in here, and looking at the sky I thought about celestia, and I had an idea :
when i saw the clouds, there were lower clouds and higher clouds. the lower ones moved faster than the higher ones. so i thought that it would be nice to see the same effect on celestia: to have two diferent clod maps in the same planet, movinf with diferent speeds each other.
can this be done?? or we will have to put a small planet with clouds inside earth??

[HS]

Thanks very much for making this suggestion. I had also wanted to suggest that more than one cloud layer would be a good thing. However I felt the need for more than one layer for a different reason.

If Celestia had more than one cloud layer one of the layers could be used for polar ice caps. This layer could then be made to revolve at the speed of the earth and Celestia users could vary such polar layers at different seasons while retaining the Earth texture they prefered. That is the user could keep using his or her favorite texture and add appropriate layers as wanted. In this way a basic texture could be used and polar caps or political maps could be added when wanted.

[HS]

Thanks very much for making this suggestion. I had also wanted to suggest that more than one cloud layer would be a good thing. However I felt the need for more than one layer for a different reason.

If Celestia had more than one cloud layer one of the layers could be used for polar ice caps. This layer could then be made to revolve at the speed of the earth and Celestia users could vary such polar layers at different seasons while retaining the Earth texture they prefered. That is the user could keep using his or her favorite texture and add appropriate layers as wanted. In this way a basic texture could be used and polar caps or political maps could be added when wanted.

[TERRIER]

Going onto a slightly different tack, I would like to see the aurora in the atmosphere, maybe done by incorporating into a cloud texture?

As for the changing polar caps/ seasonal variation textures, I wouldn't think a cloud map would have to be used. I reckon you could get away with the alternate texture feature!

It would be nice to see this run automatically by use of beginning and ending dates if possible?

regards
TERRIER

[HS]

Thanks for your response.

I am aware of alternate textures, but let me explain.

I use the 32k Blue Marble Virtual Earth Texture and the Realistic-Earth 16k Texture as well as some others. If a cloud layers (among multiple cloud layers) could be created with north hemisphere winter polar cap and another one with south hemisphere winter polar cap, I would then be able to continue using my favorite Earth Textures and just overlay the appropriate seasonal "cloud layer."

By using such layers, rather than alternate textures, it would not be necessary for texture designers to "create the wheel all over again." They could concentrate on such layers rather than having to design a whole planet texture, in addition it would save the time necessary for Celestia users to download a whole new texture (presumably an alternate texture).

It is possible to get an aurora view without having a separate layer. I have created quite acceptable auroras by combining the very top and bottom segments from Jupiter NightMaps (the ones with auroras) with Earth NightMaps. Using just MSPaint I've cut and pasted the aurora segments on to the tops and bottoms of my selected Earth NightMaps.

Hope this clarifies matters, and I hope you'll be able to create your own auroras with the hint given above.

[HS]

Thanks for your response.

I am aware of alternate textures, but let me explain.

I use the 32k Blue Marble Virtual Earth Texture and the Realistic-Earth 16k Texture as well as some others. If a cloud layers (among multiple cloud layers) could be created with north hemisphere winter polar cap and another one with south hemisphere winter polar cap, I would then be able to continue using my favorite Earth Textures and just overlay the appropriate seasonal "cloud layer."

By using such layers, rather than alternate textures, it would not be necessary for texture designers to "create the wheel all over again." They could concentrate on such layers rather than having to design a whole planet texture, in addition it would save the time necessary for Celestia users to download a whole new texture (presumably an alternate texture).

It is possible to get an aurora view without having a separate layer. I have created quite acceptable auroras by combining the very top and bottom segments from Jupiter NightMaps (the ones with auroras) with Earth NightMaps. Using just MSPaint I've cut and pasted the aurora segments on to the tops and bottoms of my selected Earth NightMaps.

Hope this clarifies matters, and I hope you'll be able to create your own auroras with the hint given above.

[astrum aspicio]

I just got done talking briefly about changing "cloud layers" into a more generalized layering system with various composition/masking options. This would be a very welcome addition indeed.

Right click on Earth, select "the polar ice cap layer mask" and tada!

[TERRIER]

Hello HS

Thanks for clarifying things, however I still think using the current alternate surface feature would be easier for showing seasonal polar caps.

I'm using Grant's longitude/latitude grid overlay as another of my alternate textures (which barring the grid pattern is totally transparent) over the top of my realistic earth textures by Don Edwards which I've renamed. Here is the ssc;

Code: Select all

AltSurface "Grid Overlay" "Sol/Earth"
{
   Texture "earthnewdon.dds"
   SpecularTexture "earth-spec.ctx"
   NormalMap "earth-normal.ctx"
   SpecularColor [ 0.5 0.5 0.55 ]
   SpecularPower 25.0
   HazeColor [ 1 1 1]
   HazeDensity 0.3
   OverlayTexture "earthgridTCA.png"
}

This allows all the features to show through when using the grid overlay with the Earth.

I'm sure a mainly transparent texture showing only the poles could be created without having to incorporate the rest of the Earth texture.
Making the texture designers job easier and allowing the download size to be relatively small.

I'm also wondering if you'd want these alternative polar caps to act like VT's and increase in detail as you get closer? Again this is a possibility that is already being achieved in the altenate textures feature. I have the political borders overlay VT's installed, which again are nearly totally transparent. They go up to a level2 VT detail plus a small amount of finer level3 detail as well.

I do agree with you that you won't be able to overlay this on top of your Blue Marble Texture if you are running it as an alternate texture. It looks like you can't overlay an alternate texture over another alternate texture.

Maybe this could be resolved? If not then I'll admit defeat and wait to see if the multi-layer 'clouds' would be a better option!

Thanks for the aurora tip, I'm currently running Don E's nightlights and aurora which looks very good, it might be worth having a go at creating some others for some more variety.
However I also like using the 'goto surface' feature and it'd be good to see the aurora above my head instead of under my feet! (Hey I could visit some of Ziggy's Antarctic bases for some spectacular views ) Currently this is just a surface texture feature, which I guess yours are?

regards
TERRIER

[John Van Vliet]

the problem of more than 1 cloud texture lies in the hardwere and not celestia . A nvidia gforce can only handle a single 2k cloud texture , so we will have to wait until the hardwere cheches up with the softwere .

[Guest]

john,

First I'd like to point out that it should come as no surprise that I'm not familiar with Celestia's rendering code. At all. But couldn't it do multiple layers by doing several passes? First pass do layer1, second pass do layer2, etc.

This could also, of course, all be done in software on the host CPU, but performance would take a serious dive. The latest dx9/opengl2.0 compliant hardware would be able to handle image processing in their respective hardware, as well.

Hopefully one of you fellas can clarify any confusion I might have.

[chris]

There's no hardware limit that prevents Celestia from using multiple cloud layers. They can be rendered with one cloud layer per pass. In fact if the clouds are allowed to be at different heights, then multiple passes are in fact required.

--Chris

[JackHiggins]

Great! So... Is this a feature we might be able to see anytime soon...? (I know you're really busy with all the other feature requests though!)