Mapping of multiple in-game planets

[isostone]

Hello! I'm currently working on a project for a character who is a amateur (but enthusiastic) cartographer. They exist in the world of Outer Wilds, a game with multiple simulated planets(none more than a few kilometers in diameter). The simulated planets each have their own gimmicks (i.e Brittle Hollow, a hollow planet with a black hole in the center. Its crust falls into the black hole during gameplay, and most of what you can explore is under the crust).
How might I go about mapping these places in a way that'd be accurate and believable in the sense that my character could have drawn them up while exploring? What sort of notes should I be taking?

Comments

[cnoocy]

A crucial chunk of your second sentence seems to have been elided.

[ariaflame]

Oof. I mean Brittle Hollow is hard to have accurate maps for, in that it was accurate when your character went through, but that doesn't mean those paths would still be there for future explorers or when they come back. And as for Dark Bramble I'm not sure how you would map that.

[silveradept]

What is the purpose of the map? Knowing what's being cataloged might help with figuring out how the mapping actually works, because that well suggest what's going to get notated and what kinds of distance units get used and so forth.

[lyorn]

I do not know the setting, but mapping is a problem I often run into when world building, and though I think it's a very nice problem, it often defeats me.

If the result is not intended to look like a map, you can determine a fixed point and define directions, or define a coordinate system that can be two dimensional (planet surface) or three dimensional (accounting for elevation or depth). Finding a fixed point to leverage a planet can be an interesting task in itself. Once you have your framework, note the coordinates relative the the fixed point, or in the coordinate system.

For two dimensional (surface-only), distance and direction from the fixed point will ususally suffice to find some spot again. A coordinate system would give you something similar to GPS data.

Calculation of distances between points requires some spherical geometry, unless they are close enough to each other (for space rubble sized planets, that would be very close).

Actually drawing a two-dimensional planetary map that sets the points in the right locations has been a challenging task for cartographers since people realised that the Earth is round. It will be even more fun with less-round planets, I guess.

I've been looking for some online tool to help with three-dimensional mapping a while ago, but did not find a sufficiently easy to handle one for my purpose.

If you cannot define directions relative to the planet because it tumbles through space without an axis or a magnetic field, you can still define a coordinate system using landmarks. In the end it's all triangles anyway.