Planetside Software Forums

General => Terragen Discussion => Topic started by: mash on April 22, 2021, 07:55:43 AM

Title: Moon Planet settings
Post by: mash on April 22, 2021, 07:55:43 AM
Hi, I'm doing renders with nasa Lunar data and I want to make sure I have the Planet settings correct for the Moon.
I set the planet radius to 1.738e+06 and center to -1.738e+06
Does the distance also need to be set to 1.738e+06 ?

Capture.JPG
Title: Re: Moon Planet settings
Post by: N-drju on April 26, 2021, 03:33:19 AM
Hello Mash,

Since it's been a few days and no replies have been made yet, I thought I'd chime in.


Sadly, I don't use the Planet object frequently but here are a few suggestions:

1. To put it bluntly - I never used the "distance" settings in other planets and just use the translate arrows to transfer the planet to the right spot in the sky. Of course, this does not apply when you need accurate lengths. However, I find the standard translate controls to do the job just fine.

2. I think that the "distance" setting here, means a distance from zero coordinates to the center of the respective planet. Not a distance from one object to another. But even if I'm mistaken, then the distance from Earth to Moon is approximately 384 000 kilometers. In that case, I think you'll agree that a number of 1.738e+06 is nowhere near the actual distance between us and the Silver Globe (if this was what you were after).
Title: Re: Moon Planet settings
Post by: sboerner on April 26, 2021, 09:24:09 AM
Try these settings for a planet object:

Radius: 1.7381e+06
Distance: 3.844e+08

This is actually measuring the distance from the scene origin, which is the north pole of the earth, but it should be close enough.

Use the Heading and Elevation fields to position the moon in the sky.

Important: You'll also need to increase the diameter of the Background object, otherwise it will block the moon during renderings. A value of -4e+8 should work. (The negative sign inverts the sphere so any applied textures, such as a starfield, will render properly.)

The timing of your question is interesting. I was just looking into this!
Title: Re: Moon Planet settings
Post by: mash on April 26, 2021, 05:54:09 PM
Hi, thanks for the answers. Just to be clear I'm not trying to put the moon in Earths Sky. 
I'm trying to simulate the correct curvature and lighting as if you were standing on the moon. 
I may be thinking about it all wrong. 
Thanks,
Michael
Title: Re: Moon Planet settings
Post by: sboerner on April 26, 2021, 08:12:41 PM
Of course, sorry. In that case you had it exactly right. Distance should be 1.738e+06 and elevation should be 270. Just the same as the default planet (earth), but substituting the new value.