Full screen- Just saying because it wasn't even on the list. Maybe you should have a separate list for just full version features.
Gravity Guide- Yeah, But I was thinking about more advanced stuff, like experiments you can try, why r^1 has ellipses and all, and how the gravity simulator works. That stuff would probably be better as an add-on to yours, though.
Different screens- I got this idea from the different layers in Golly (it's a Game of Life simulator if you didn't know that already). Also, I was thinking this could be a good thing to default to 'off' (so as to not confuse new users), but which you could later toggle on in the options. I'm also thinking that toggling other info on/off might be useful for planet displays and the regular display. That way, the information can be available, but it doesn't spam your screen because you won't toggle everything on at the same time, but rather the stuff that matters to you. You could also have a feature to jump to planets with names if finding a named planet ever becomes a problem.
Save slots- I thought this would be such a time and hassle-saver to not have to save the code elsewhere. I think this is a really good thing for you to implement.
Leaderboards- That was just a joke (I meant ignore the whole sentence when I said scratch that, not just the part in parentheses). I'm not sure if you got the cookie clicker reference...
No, boost would be speed boost (in the direction the planet is traveling). Like if you wanted to move a planet into a higher energy orbit. This is kind of a FSP inspired idea. I'm also thinking about how orbits might look if you had the planet constantly accelerating like there was an engine strapped on. Not sure if this would be currently implementable, though, because it depends heavily on a planet's rotation, and rotation has not been implemented. You could have a constant boost in the planet's direction of travel, though, and that wouldn't require rotation. It would be like inertia, except it creates more acceleration.
Definitely-an-edit: Yeah, there's other useful information that could be displayed, too. You can have this information not shown by default to make it less spammy, but other numbers could be:
# of planets selected
Velocity vector of overall selection
Pointing out any named or described planets
Heaviest planet, lightest planet, fastest, slowest, etc.
Average and mean mass, velocity (mean velocity would obviously be the velocity vector for the whole group, but average velocity might be interesting), age, distance traveled, etc.
Area of selection
Time your selection has existed
A zoom to your selection option
Anyways, much of that information is probably useless anyways, so you decide which you're actually going to add in to the game. That's your job. My job is to fantasize the perfect Gravity Simulator where everything you could and couldn't possibly imagine exists and then idea storm it's features, hoping your Gravity Simulator gets somewhere close to that fantasy.
I also thought of this sort of general relativity stuff: slowing down time in a certain region of space. Adding space to a certain region. Ooh maybe you could add space in a way that makes it like HYPERBOLA LAND!!!!!
Sorry, non-Euclidean geometry just excites me.
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