chengsun

9 ms·

1.
by chengsun 9y ago
This optimisation is actually fully correct if int is 32-bits wide. This is because doubles have a 52-bit mantissa, which means that they can exactly represent all integers up to 2^53 in magnitude. However you are right that the optimisatio
2.
by chengsun 9y ago
No, you're talking about a different problem: that of counting the total number of n-queens solutions. The original article is talking about the problem of deciding, given a partial placement of queens, whether it can be completed by a
3.
by chengsun 10y ago
This is only true assuming that P != NP, which is still an unsolved question. Furthermore, NP-completeness only applies to decision problems. In this case the paper explores the problem of deciding whether or not there exists a path which w
4.
by chengsun 11y ago
Also, a fantastic visual guide is the documentary film "Moleman 2" (2011). It's freely available to watch on YouTube; highly recommended: https://www.youtube.com/watch?v=iRkZcTg1JWU
5.
by chengsun 11y ago
This is not true in general. Consider two independent fair die rolls, with A and C being the outcomes. Let B be the sum of the outcomes. The higher A is, the higher B is likely to be, so A and B are positively correlated. So are B and C. Ho
6.
by chengsun 11y ago
Video codecs are good at compressing stills, so there's very little overhead in playing such a video when only the audio is desired. That being said, YouTube does also encode audio-only versions of all their videos; they're not av
7.
by chengsun 11y ago
Sundown is probably the most well-known one: http://www.demoparty.net/sundown2015/ http://www.sundowndemoparty.net/ [not updated for 2015 yet]
8.
by chengsun 12y ago
Ah, that clears things up. Thanks for the info.
9.
by chengsun 12y ago
This was worded misleadingly. This is indeed a DDoS: code has been injected to load the Github pages in the background using XHR without the user's knowledge. The host page itself is not redirected (or visibly affected in any way[1]).
10.
by chengsun 12y ago
The source for each sample is all in index.html: https://github.com/mrdoob/texgen.js/blob/master/index.html
11.
by chengsun 12y ago
Unfortunately the effects that you describe are nontrivial. The method of water simulation that is used here doesn't lend itself to simulating the effects of things like water tension or breaking waves. This is because the water surfac
12.
by chengsun 12y ago
Even so, O(4^n) != O(8^n); there is no constant k such that k * 4^n >= 8^n.
13.
by chengsun 12y ago
Óscar Toledo G. has notably written various tiny, strong and highly obfuscated chess engines in C (winning the IOCCC twice) and JavaScript (2nd place in the first JS1k). He's even written a 170 page book to serve as a reference to the
14.
Android crypto blunder exposes users to highly privileged malware(arstechnica.com)
15 points by chengsun 12y ago|1 comments
15.
by chengsun 12y ago
Don't forget https://www.scenemusic.net/demovibes/ - demoscene streaming music radio
16.
by chengsun 12y ago
The trick is to perform damping around the edges in a hidden border around the heightmap. Say you wanted to simulate a 500x500 heightmap. You would actually calculate the results for a 700x700 heightmap, (which contains a hidden border of w
17.
by chengsun 12y ago
Good point, but I believe you mean "pidgin of a language"!
18.
by chengsun 12y ago
On the flip side of the coin, there's ries, which takes a number and finds a mathematical expression that approximates it: http://mrob.com/pub/ries/
19.
by chengsun 12y ago
Řrřola (a famous demoscene coder [1]) found a far better constant than the original (a 2.7-fold accuracy improvement) by using an optimisation algorithm over all three constants present in the original inverse square hack. His algorithm and
20.
by chengsun 13y ago
You'll need to allow brick.im if you have NoScript, because NoScript blocks web fonts.
21.
by chengsun 13y ago
Shameless plug: a while back I wrote an assembler-and-VM for a similarly hypothetical assembly language that I was studying in class. Just for kicks, I wondered if I could fit the entire thing into 1KB of JavaScript, whilst including featur
22.
by chengsun 13y ago
Online radio dedicated to demoscene music: https://www.scenemusic.net/demovibes/
23.
by chengsun 13y ago
Yep, see gasman's JSModPlayer: http://jsspeccy.zxdemo.org/jsmodplayer/
24.
by chengsun 13y ago
It was introduced in Firefox 5 [1]. You can change it in about:config by tweaking "dom.min_background_timeout_value" to a lower value (in milliseconds). [1]: https://bugzilla.mozilla.org/show_bug.cgi?id=633421
25.
by chengsun 13y ago
Also check out this JavaScript Amiga MOD player by gasman: http://jsspeccy.zxdemo.org/jsmodplayer/
26.
by chengsun 13y ago
This is probably because Firefox (and Chrome) clamps the setTimeout interval of background tabs to 1 second to improve performance.
27.
by chengsun 13y ago
Not to be unappreciative of this cool demo, but here's a snake game I wrote a while ago that clocks in at 41 "commented lines" of code, and minifies to under 1KB of code whilst including setting up the DOM and CSS (which is c
28.
by chengsun 13y ago
You can change the phase by holding ctrl-shift and dragging the circle. If you want a negative value just use the absolute magnitude with the component in antiphase.
29.
by chengsun 13y ago
The nth circle from the right is n times the speed of the first circle.
30.
by chengsun 13y ago
It is, but Nestle have allowed Google to use the name, as part of a mutual promotion.

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