3 HN users recommended this explainer3 months2021–2026score 3
Years with an HN recommendation, 2007–2026
Recommended among the nice visual explorations and tech demos of non-Euclidean geometry for games.
CodeParade's short devlog on how spherical geometry looks in 2D and 3D and why it feels so unusual, part of the Hyperbolica series on a non-Euclidean game.
“One of the better ones, in my opinion, because it has "normal" objects in it” (HN, 2022)
Code Parade on Youtube has some nice tech demo for non-euclidean 3D game engine. "Non-Euclidean Worlds Engine" - [link] "Spherical Geometry Is Stranger Than Hyperbolic" - [this video]
Hyperbolica is mostly about the opposite, a hyperbolic universe, but there may be some section to the game that will be in a spherical universe. There's definitely some devlog video set in a spherical universe: [this video] The end of the video suggests this will be in the final game, at least as the time that video's creation. In the meantime, the video I link is basically a video exploration of spherical geometry. One of the better ones, in my opinion, because it has "normal" objects in it, rather than floating heads or a ton of Earths or something. (Another amusing sidebar: As you can see in the video above, an inhabitant of that space would be naturally inclined to say the space curves in above them. It would take an Einstein to assert that it's actually flat, and Spherical Einstein would have a very hard time describing "flat" to anyone. You can only make things "flat" contingent on the observer being in a very particular place. If you look at the next devlog: [link] back in Hyperbolic space, you can also see that a resident of that space would naturally believe the space they are in is a sphere (albeit one of variable radius, which is weird, but still, you can look out in the world and see the curvature, obviously it's round), and it would again take an Einstein to say that it is flat. It's flat if you are exactly on the ground, but hyperbolic space exaggerates any degree to which you are above the ground to make the horizon look round.)
Video exploration of spherical geometry with normal objects.
Cool. It would also be interesting to see a hyperbolic snake. Reminds me of this video, where the dev compares spherical and hyperbolical geometries (albeit a dimension higher): [this video]
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