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[tjcbs]

I don't know if this is obvious or not. My visual intelligence is even worse than the other areas. But,

The screen is centered on a planet, which is (very quickly) orbiting a sun, clockwise. The camera is pointed parallel to the axis of rotation, so that the sun is not seen. The screen rotates around the sun, along with the planet, and orients itself with the planet, so that the planet appears stationary.

What path do the stars take across the screen?

[bdsowers]

I'm not entirely sure if this is what you're asking, but:

Assuming the stars are stationary (you're not modeling any gravitational pulls for them), they'll appear to go in the opposite direction of your planet. That is, they'll have a curved path, and it will change depending on where the planet is in its cycle.

[jgrams]

Rotating the screen around the center of the sun is the same as rotating the world around the center of the sun in the opposite direction. So if you have a circular orbit, they'll be circular arcs...

--Josh

[Christian Knudsen]

Right to left.

EDIT: Never mind. I thought the camera was pointed at the planet with the sun in the background.

[BorisTheBrave]

It's easiest to think of stars as dots on a big black sphere which is always centered on the camera (i.e. a skybox). Until you are moving light years, this approximation holds up pretty well. From this point of view, it's clear the only relevant camera motion is the roll, there's no pitch or yaw.

So they'll rotate around the screen center, due to the camera rotation to maintain the sun in the "up" direction on the screen. Any star in the dead center of the screen won't move.

[Christian Knudsen]

So they'll rotate around the screen center, due to the camera rotation to maintain the sun in the "up" direction on the screen. Any star in the dead center of the screen won't move.

Won't the stars be rotating around the sun, which is out of frame?

[Netsu]

Won't the stars be rotating around the sun, which is out of frame?

The point is they are so far away from the camera that it doesn't matter if they rotate around the sun or the screen center, it will look the same. At least if you kept the scale real it wouldn't make a difference since in relation to interstellar distances the earth and the sun are pretty much the same place, but since this is just a game the closest approximation is rotating them around the screen center and having the scale be whatever.

[Christian Knudsen]

Ahh, yes. That makes sense.