rivendell.dmitrybrant.com
Learning and science
physics simulation
SHOW HN2026
How HN took it
11 positive, 50 neutral or asking, 0 mixed, 21 critical, out of 82 comments about the project. Thread score -0.12.
Execution: 1 for, 12 againstIdea: 8 for, 5 againstDesign: 0 for, 1 against
The thread, comment by comment
Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.
positive neutral or mixed critical about another commenter or something else the maker
What HN said
What people liked
Accurate modelling of relativistic Doppler and effects, better than MIT's game
From 2 comments
At first sight, this is remarkably more accurate that the "slower speed of light" game from MIT that was made available all those years ago (~2012). Many issues with the MIT game…
adamkurkiewicz on HNThe math being simple while the effects emerge automatically is the best part. Relativity is unintuitive precisely because the consequences are so far from the formula.
Driftbench on HN
Objections
Does not work on mobile
From 3 comments
Too bad that it does not seem to work on mobile. I did not find any way to move around (add arrow buttons? Are we supposed to move around?) and if I double tap I change the…
pmontra on HNThis only works on a desktop? Is there any way to interact with it on a phone?
buttercraft on HNDoesn’t work on mobile Checks repo. Contributors: @dbrant dbrantDmitry Brant @claude claudeClaude I’m tired boss
realmanrealmanu on HN
Controls for W and S feel reversed
From 2 comments
I don't understand movement: "W" makes me appear to move backwards, "S" makes me appear to move forwards. When I use space to stop, I move back to where I started. Is this a bug…
gwbas1c on HNFeels like W goes back (instead of forwards like in an FPS), and S goes forward. Is that intended or just my keyboard being weird? EDIT: ah, by setting 'Speed of light' parameter…
nomilk on HN
Mouse cursor gets captured or disappears in some browsers
From 3 comments
Sidenote but this page took control of my cursor, and would not relinquish it even after I navigated away! This is on firefox.
eyeundersand on HNWarning: This page ate my mouse cursor and it went invisible when hovering on Edge browser, even after closing the tab.
jve on HNSo weird, after visiting, my mouse icon disappears!
emmelaich on HN
Requests
Add mobile controls
From 2 comments
It would be nice to add controls for mobile.
gryfft on HNYou should make it work in iPhone.
bilsbie on HN
Add direction indicator
From 1 comment
Really cool! Are you able to add an indicator showing which direction you're travelling in? It's quite confusing to start due to all the effects. I also recommend a banner that…
domhudson on HN
Questions
Whether the reduced speed of light is applied only to visuals
From 1 comment
I don’t quite get the assumptions here. If c were actually 5 km/h, causal influences would propagate much more slowly. With G unchanged, planets and stars at their current masses…
inshard on HN
Alternatives named
MIT Game Lab's A Slower Speed of Light (2012)
From 2 comments
MIT Game Lab made a take on this back in 2012. https://gamelab.mit.edu/games/a-slower-speed-of-light/
tomjakubowski on HNSee also https://gamelab.mit.edu/games/a-slower-speed-of-light/, a 2012 game that did the same thing
wging on HN
Velocity Raptor
From 1 comment
Velocity raptor is a free game that accurately simulates the effects of special relativity. It slows down the speed of light to 3m/s and you solve puzzles as a cute dinosaur.…
tristanj on HN