Celestia Forums

John Van Vliet wrote:to get a 4k image i would need to upscale the smaller 3200x1600 image
this was not created in blender, but a hacked version of "earthlike.c" from "space:nerds in space"

John,

how did you made the normal map for this ? We need a 4K version of it.

the normal was done using a 16 bit unsigned raw and NMSU , my hack of the nms tool for making a ppm from a simple cylindrical raw 16 bit SIGNED raw height map .

the same way i have made normalmaps for many years

Then is it possible to redo the normal map of the previous texture, in 4k ?

ok a 35 meg zip with 3 4k maps
texture,normal, and 16bit heightmap
-- fixed error i thought i had fixed

https://drive.google.com/file/d/0B6ZYAd08tZL-emlMc2pDeEpNUUk/view?usp=sharing

Wow ! That texture is awesome, John, thanks a lot !

You should publish your last set of textures (mars-like, giant gas and asteroids/moons) to the Motherlode.
These textures are a must, for Celestia !

Added after 4 minutes 37 seconds:
Hmm, John, I just noticed a seam on the normal map. The base texture is perfect (no seam), but the normal map has a defect on a side :

thought i fixed that, Fixed NOW

new zip

John, did you fixed the seam on your normal map ?

Here are two views of a strange world, in a far away galaxy (M31), with some nebulea visible in the background :



Both textures from John VV.

Added after 4 hours 2 minutes:
I was a long time that I didn't cruised into Celestia's space like this. What an experience !

Three views from inside some sprites nebulae in two galaxies (M33 and M81) :

Cham wrote:Three views from inside some sprites nebulae in two galaxies (M33 and M81) :

I know Celestia is capable of that, why haven't I seen an addon yet? There are no sprite nebulae in default (except globular clusters and galaxies themselves if you count that). So how to use them?

FarGetaNik wrote:I know Celestia is capable of that, why haven't I seen an addon yet? There are no sprite nebulae in default (except globular clusters and galaxies themselves if you count that). So how to use them?

The problem with sprites nebulae in Celestia 1.6.1 is that they are still rendered as a very luminous pixel while you are standing very very far away from the model. The sprites do not fade away with distance. The special Celestia 1.7.0 for OS X that I published elsewhere on this forum had fixed this important bug. It's a pitty that this version never got published as the official version, especially since it's 64bit ! See this thread :

viewtopic.php?f=4&t=17423

With Celestia 1.6.1, sprites nebulae could be used as SSC objects though, to represent small planetary nebulae for example.

Added after 4 hours 3 minutes:
By inverting the colors of John's texture, I could get a nice variation. This is usefeull for more variety in a system :

Left side of the picture below is John's original texture, with a color blending at the SSC level only :

Right part of the picture is the same texture, inverted, with a bit more contrast and same color blending :


(This looks a bit like a planet that have gone thermonuclear war and lost all of its atmosphere ! )

Cham wrote:Right part of the picture is the same texture, inverted, with a bit more contrast and same color blending :

Maybe you could get some different structures by using a high-pass and combining it with a blurred and inverted copy.
personally I think the normal effect is to intense, so lowering the contrast in the normalmap (and maybe mirroring the set of textures) might give some more variety.

Playing with John VV's textures, here are three "dramatic" views of a system in Andromeda's galaxy (M31) :




Celestia is awesome to make views like these !

I need to place an alien probe in this system !

There's so much worlds, out there !

I'm rediscovering many worlds. I didn't explored Celestia's space since a pretty long time ...

The Black Acropolis, a 'Snailshell' configuration Dyson swarm in Orion's Arm





Each cylinder contains a separate environment, many times larger than a planet; they are linked into rings, each ring orbiting as a slightly different inclination.
http://www.orionsarm.com/eg-article/48000db9a9c2f

can be downloaded here
https://onedrive.live.com/redir.aspx?cid=9438a296 ... B!108&authkey=!AHfXTfgK2aGSmXY

That's so beautiful I wonder if such a configuration was stable or of perturbations would cause it to collapse eventually.

Even if they are subject to perturbations, there is plenty of available energy for stationkeeping. And to protect against comets.

Steve.Bowers wrote:Even if they are subject to perturbations, there is plenty of available energy for stationkeeping. And to protect against comets.

This is only reasonable if they have a very small mass (hence low density) or their own gravity alone might cause chaos, considering they are planet-sized! I can believe the solar energy would be enough to counter external perturbations.

The latest mars-like texture from John VV, in Andromeda's galaxy. I'll populate the sunlike stars close to a nebula model, for the views...

Here is an image from Hades in the Avatar system by Milosz21:

what happened to the images ? i can't look at them .

I'll try to keep the forum alive by posting some exoplanet pictures here, instead of on the Discord.

55 Cancri e has a very close orbit...

Proxima Centauri and planet "b", with aurorae!
Note: Sirius and Betelgeuse, which appear very close from Proxima, can be seen at the image center.

Proxima c, recently confirmed; probably a small gas planet.

TESS with its first planet, Pi Mensae c.

HIP 41378 f, which based on two recent papers could potentially have a ring system.


Added after 5 minutes 24 seconds:
HD 189733 b, with NASA's texture for it.

HD 209458 b, with its evaporating atmosphere defined as a comet tail.
Note: I'm not sure if this is realistic. For WASP-12b I've just defined a "puffy" atmosphere.

Of course there has to be a TRAPPIST-1 picture...transit of planet "d", from orbit around "e".