Astronomy in SH5

Cerberus62 · 01-09-11, 09:56 AM

I'm sure that whatever we try, it wouldn't fix this error. That's because of the simple method SH5 calculates the position and displays the image of the Moon.

First: Orbital planes and trajectories aren't calculated precisely in this game. Second: It's not possible to simulate the different aspects of a sunlit body with 16 images. Even if you would rotate the images it would look wrong, because you would incline the axis of the Moon together with the aspect of the surface.

I reworked the Moon.dds and Moon_halo.dds texture files and replaced each single phase by it's counterpart. After this I often found the correct side of the Moon facing the Sun, but not always. So this error only occured less frequently. But the rework introduced another error. Now the lunar phases develop in the wrong direction: Starting with New moon you'll see the waning crescent followed by the last quarter and so on during the synodic cycle.

To get rid of this problem we would need a three-dimensional textured spherical body, illuminated by an almost point-shaped source of light. I think that's far beyond the possibilities of the SH5 game engine.

For those who are interested in astronomy and still don't know the wonderful freeware program Celestia: http://www.shatters.net/celestia/

01-09-11, 09:56 AM	#20
Cerberus62 A-ganger Join Date: May 2010 Location: 52° 31' N, 13° 24' E Posts: 76 Downloads: 75 Uploads: 0	I'm sure that whatever we try, it wouldn't fix this error. That's because of the simple method SH5 calculates the position and displays the image of the Moon. First: Orbital planes and trajectories aren't calculated precisely in this game. Second: It's not possible to simulate the different aspects of a sunlit body with 16 images. Even if you would rotate the images it would look wrong, because you would incline the axis of the Moon together with the aspect of the surface. I reworked the Moon.dds and Moon_halo.dds texture files and replaced each single phase by it's counterpart. After this I often found the correct side of the Moon facing the Sun, but not always. So this error only occured less frequently. But the rework introduced another error. Now the lunar phases develop in the wrong direction: Starting with New moon you'll see the waning crescent followed by the last quarter and so on during the synodic cycle. To get rid of this problem we would need a three-dimensional textured spherical body, illuminated by an almost point-shaped source of light. I think that's far beyond the possibilities of the SH5 game engine. For those who are interested in astronomy and still don't know the wonderful freeware program Celestia: http://www.shatters.net/celestia/ Last edited by Cerberus62; 01-09-11 at 10:14 AM.