Monday, August 19, 2019

[dicccdrq] Fun with geodesics

Consider a game with the following mechanic: one is given a 3D shape, an origin point, a destination point, and an off-geodesic point all on the surface of the shape.  When traveling the shortest path from the origin to the destination, is the off-geodesic point to the left or right of the path?

Best is with a physical model.  Globe and 3 cities for a sphere.  Other shapes could follow a similar principle: a physical model with labeled locations (maybe regions labeled by unique shape or color pattern) allows the player to locate (by eyeballing) points that are displayed on screen on a zoomed 2D map projection.  A graphical solution, if wanted, is given also on the display in map projection.

Purely electronic is trickier.  Easiest is to fix the shape to be a box, and put rectangular display panels on the 6 faces.  For an arbitrary fixed shape with a center (probably convex), an electron gun and phosphor surface seems good for 3 points and the solution line, in the style of old oscilloscopes.  Other methods of projection from the center, e.g., laser, would also work.  Previously, spherical display.  The ultimate is a shapeshifting physical display, essentially Odo or the T-1000 Terminator.

Virtual reality (VR) and augmented reality (AR) could offer nice interfaces.

More complicated games: players complete to trying to draw a path shorter than those drawn by other players.  Perhaps in the style of a racing game.  Also previously, billiards.

Inspiration was complicated but doable algorithms for computing geodesics on a triaxial ellipsoid.

No comments :