parametricity.com
Learning and science
interactive math visualisation
SHOW HN2015
149points
34comments
#138of 2,565 in 2015
Top 6%of 2015 by points
How HN took it
CuriousMostly questions and neutral comments
4 positive, 14 neutral or asking, 0 mixed, 4 critical, out of 22 comments about the project. Thread score +0.06.
Idea: 3 for, 0 againstExecution: 0 for, 3 againstDesign: 1 for, 0 againstDocs: 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
Objections
Numerical inaccuracy causes loops not to close and paths to drift
From 4 comments
Looks really cool! One question though, how did you implement the movement? When you press up and left at the same time in the flat you'd expect to trace the same circle over and…
Gladdyu on HNLooking at the source code (I think this is it: https://github.com/imeckler/diffgeo/blob/master/Main.elm#L320, https://github.com/imeckler/diffgeo/blob/master/Native/ODE.js#L19)…
conistonwater on HNGreat work! Can you add the Klein model? It's kind of interesting that moving while turning at a constant rate in the hyperbolic plane makes you gradually "drift". Is that…
cousin_it on HNYeah, I'm pretty sure it's an artifact. I'm seeing the same drift in the cylinder geometry, which definitely shouldn't be happening. A cylinder has the same internal geometry as…
cousin_it on HN
Page scrollbars flicker and shake in some browsers
From 2 comments
I tried this in Firefox (latest) and the scrollbars kept perpetually disappearing/reappearing, causing the entire page to just shake violently.
BHSPitMonkey on HNI'm on Ubuntu 15.04 with Firefox 39.0+build5-0ubuntu0.15.04.1, and with my window maximized the <body> alternates between 1411x689px and 1404x689px (with the difference being…
BHSPitMonkey on HN
Zoom controls are not discoverable
From 2 comments
>Use the up arrow key to go forward along the geodesic in the direction you're facing and the left and right arrow keys to change direction. > >Scroll to zoom, click and drag to…
dbbolton on HNUsing a two finger scroll on my touchpad works fine. I'd try that or a scroll wheel on a mouse or similar.
smeyer on HN
Requests
Discrete step and rotation moves, Logo turtle style
From 2 comments
Suggestion: allow me to move in discrete steps of a specified length, and rotate in discrete steps too. Then I can see what happens in different geometries when I go forward n,…
jameshart on HNThis is really cool. My suggestion is similar to (perhaps the same as) jameshart's. I want to be able to form a sequence of known steps in flat space (say, draw a square), then…
dhimes on HN
Show the path line ahead of the arrow
From 1 comment
Feature request: always show the line that you will walk when you keep going forward (e.g. in a light color).
amelius on HN
Support moving backwards
From 1 comment
Really cool! Yet another feature request: support moving backwards
blt on HN
Use the arrow's frame of reference
From 1 comment
Feature suggestion: use the arrow's frame of reference instead of a global one.
ThrustVectoring on HN
Add a Klein model view
From 1 comment
Great work! Can you add the Klein model? It's kind of interesting that moving while turning at a constant rate in the hyperbolic plane makes you gradually "drift". Is that…
cousin_it on HN
Questions
Why do paths drift or fail to be periodic when turning constantly?
From 2 comments
Looks really cool! One question though, how did you implement the movement? When you press up and left at the same time in the flat you'd expect to trace the same circle over and…
Gladdyu on HNGreat work! Can you add the Klein model? It's kind of interesting that moving while turning at a constant rate in the hyperbolic plane makes you gradually "drift". Is that…
cousin_it on HN
Alternatives named
Jeff Weeks' Curved Spaces
From 1 comment
Jeff Weeks has done some excellent stuff. His Curved Spaces[0], lets you fly around funny 3 manifolds. [0]: http://www.geometrygames.org/CurvedSpaces/index.html
ihm on HN
HyperRogue
From 2 comments
It ain't VR, but check out HyperRogue: A roguelike game in hyperbolic space. http://www.roguetemple.com/z/hyper/
Filligree on HNThis is awesome! Reminds me of a game that was featured recently on HN: HyperRogue[0]. It's a simple roguelike on a hyperbolic plane. [0] - http://www.roguetemple.com/z/hyper/
TeMPOraL on HN