Constellation lines are not drawn if some stars are not visible

[danielortiz]

I noticed that the constellation lines are only drawn when both points (stars) are being rendered.

with the whole constellation visible

with part of the constellation out of sight

I wonder if that's intentional. If not, how would you go about fixing it? I'd be down to try to push a PR to fix but I could use some guidance on how since I don't understand much of the astronomy side of it

[slowe]

The code draws simple lines between the two stars and so it avoids drawing lines when one of the stars is outside the view. In the projection you are using there, the stars that aren't rendered are behind you. If you just "join the dots" you can get distorted/misleading lines in some cases so the lesser "bad" situation was to not draw them.

[slowe]

If you were doing better/fuller 3D rendering and drawing lines around a sphere (rather than joining two points on a sphere) this wouldn't be an issue. That would need complete re-design of the rendering or the addition of a "heavy" library that can do full 3D stuff better. I'm trying to keep the size of this project down.