Quote:Original post by abadosa
The problem now is that I want to move the inhabitants on the surface of the planet but not in terms of spherical coordinates. To put it simply, I need to move and rotate these entities in a "local way" (like you would do in a plane) without thinking in angles, latitudes or longitudes.

Did you read the thread that I linked to? What about the Gamasutra article?

Quote:Original post by SiS-Shadowman
It's not impossible. In order to make them move in curve you simply need to change the velocity vector over time. The example I gave you above used a constant velocity but can simply use any formula you want to make the velocity change.

Again, I would seriously not use spherical coordinates for this. First of all, the methods described in the thread and article mentioned previously will work for any type of irregular surface, not just spheres. Also, it seems to me that it'd take a bit of effort to map linear motion to motion in latitude/longitude space in a way that would make sense.

Now, maybe there's some tricky math you can use to make it all work (and maybe it's a 'solved problem' for applications used for navigation or what have you), but I'm not sure why you'd bother with it for something like this. I'm pretty sure the methods described in the thread and article are what's typically used for games that involve motion over arbitrarily oriented surfaces, and for what it's worth, I've found these methods to work well in practice.

That's just my view on it though.

Yep, I'm saying that your method could be the best. As I said, I've read the other thread and the article about five times, but I don't understand the code you are using in there.

You start talking about a forward and a yaw variables that I'm not familiar with. Putting these lines of code in a program won't do anything if I can't understand the basis.

Anyway, thank you all again for the efforts ;)

Oh, there's no problem with my algebra. The real problem was that I didn't understand the "nomenclature" for "forward" and "yaw". Now I know what these variables mean and I'm working to get it right. The method is pretty simpler than the one using spherical coords.

Thank you!