Reverse-EngineeringExploring the TRS-80’s Color BASIC’s Random Number Function Although these days we get to tap into many sources of entropy to give a pretty good illusion of randomness, home computers back in t...<br><br><a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Retrocomputing" target="_blank">#Retrocomputing</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Reverse" target="_blank">#Reverse</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Engineering" target="_blank">#Engineering</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/basic" target="_blank">#basic</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/pseudorandom" target="_blank">#pseudorandom</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/trs-80" target="_blank">#trs-80</a><br><br><a href="https://hackaday.com/2025/08/08/exploring-the-trs-80s-color-basics-random-number-function/" rel="nofollow noopener" target="_blank">Origin</a> | <a href="https://awakari.com/sub-details.html?id=Reverse-Engineering" rel="nofollow noopener" target="_blank">Interest</a> | <a href="https://awakari.com/pub-msg.html?id=S740WnYcUcKPQSC1tSU4lLnycCm&interestId=Reverse-Engineering" rel="nofollow noopener" target="_blank">Match</a>
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#pseudorandom
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IT News<p>Exploring the TRS-80’s Color BASIC’s Random Number Function - Although these days we get to tap into many sources of entropy to give a pretty go... - <a href="https://hackaday.com/2025/08/08/exploring-the-trs-80s-color-basics-random-number-function/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">hackaday.com/2025/08/08/explor</span><span class="invisible">ing-the-trs-80s-color-basics-random-number-function/</span></a> <a href="https://schleuss.online/tags/reverseengineering" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>reverseengineering</span></a> <a href="https://schleuss.online/tags/retrocomputing" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>retrocomputing</span></a> <a href="https://schleuss.online/tags/pseudorandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudorandom</span></a> <a href="https://schleuss.online/tags/trs" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>trs</span></a>-80 <a href="https://schleuss.online/tags/basic" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>basic</span></a></p>
FunctionalProgrammingExploring the TRS-80’s Color BASIC’s Random Number Function Although these days we get to tap into many sources of entropy to give a pretty good illusion of randomness, home computers back in t...<br><br><a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Retrocomputing" target="_blank">#Retrocomputing</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Reverse" target="_blank">#Reverse</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Engineering" target="_blank">#Engineering</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/basic" target="_blank">#basic</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/pseudorandom" target="_blank">#pseudorandom</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/trs-80" target="_blank">#trs-80</a><br><br><a href="https://hackaday.com/2025/08/08/exploring-the-trs-80s-color-basics-random-number-function/" rel="nofollow noopener" target="_blank">Origin</a> | <a href="https://awakari.com/sub-details.html?id=FunctionalProgramming" rel="nofollow noopener" target="_blank">Interest</a> | <a href="https://awakari.com/pub-msg.html?id=6hFTNuDOFL45qMjk1WQIEQnIMWe&interestId=FunctionalProgramming" rel="nofollow noopener" target="_blank">Match</a>
FunctionalProgrammingProbability: A Halloween Puzzle Introduction Though Halloween is months away, I found the followi...<br><br><a href="http://matlabdatamining.blogspot.com/2014/04/probability-hallowween-puzzle.html" rel="nofollow noopener" target="_blank">http://matlabdatamining.blogspot.com/2014/04/probability-hallowween-puzzle.html</a><br><br><a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/candy" target="_blank">#candy</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Halloween" target="_blank">#Halloween</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Halloween" target="_blank">#Halloween</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Probability" target="_blank">#Probability</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Puzzler" target="_blank">#Puzzler</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Monte" target="_blank">#Monte</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/Carlo" target="_blank">#Carlo</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/probability" target="_blank">#probability</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/pseudorandom" target="_blank">#pseudorandom</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/puzzle" target="_blank">#puzzle</a> <a rel="nofollow noopener" class="mention hashtag" href="https://mastodon.social/tags/random" target="_blank">#random</a><br><br><a href="https://awakari.com/pub-msg.html?id=2bRUBjPcPGYNi0OO5VX0tfi4Wsi" rel="nofollow noopener" target="_blank">Event Attributes</a>
zirias (on snac)Just in case anyone else ever needs a <a href="https://snac.bsd.cafe?t=pseudorandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#pseudorandom</a> <a href="https://snac.bsd.cafe?t=guid" class="mention hashtag" rel="nofollow noopener" target="_blank">#Guid</a> generator for <a href="https://snac.bsd.cafe?t=dotnet" class="mention hashtag" rel="nofollow noopener" target="_blank">#dotnet</a>, here's what I finally did:<br><br><pre> private const int guidSize = 16;<br> private const int guidStrLen = (guidSize * 2) + 4;<br> private readonly StringBuilder guidBuilder = new(guidStrLen, guidStrLen);<br><br> private string CreatePseudoRandomGuidString(Random r)<br> {<br> var bytes = new byte[guidSize];<br> r.NextBytes(bytes);<br><br> // Generate a valid UUID-v4 as per RFC 4122, section 4.4<br> bytes[6] = (byte)((bytes[6] & 0xfU) | (4U << 4)); // version 4<br> bytes[8] = (byte)((bytes[8] & 0x3fU) | 0x80U); // variant 1<br><br> // Format as a string. We don't use the System.Guid class here<br> // because it uses some mixed endian internal format which might<br> // not be portable.<br> guidBuilder.Clear();<br> for (int i = 0; i < guidSize; ++i)<br> {<br> guidBuilder.Append(bytes[i].ToString("x2"));<br> if (i % 2 != 0 && i > 2 && i < 10) guidBuilder.Append('-');<br> }<br> return guidBuilder.ToString();<br> }<br></pre>To get a reproducable sequence of pseudo-random Guids, just seed the <code>Random</code> instance with a fixed value before calling this the first time.<br>
Mark Gritter<p>The original Rogue level algorithm picks a width for each room between 4 and 25, and a height between 4 and 7.</p><p>Ignoring "gone" rooms, that gives 22^9 * 4^9 possibilities with only a 32-bit seed. So some combinations of rooms must be impossible! How does the subspace of rooms produced by the limited seed space compare with the theoretical distribution if rnd() was really random?</p><p>Weekend project, maybe? I have been thinking ever since <a href="https://mathstodon.xyz/tags/RoguelikeCelebration" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>RoguelikeCelebration</span></a> about how small RNG seeds (or poor PRNG algorithms) limit the expressive range of PCG in ways that might be unexpected.</p><p><a href="https://mathstodon.xyz/tags/ProceduralContentGeneration" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ProceduralContentGeneration</span></a> <a href="https://mathstodon.xyz/tags/PseudoRandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>PseudoRandom</span></a> <a href="https://mathstodon.xyz/tags/Rogue" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Rogue</span></a></p>
Kevin Karhan :verified:<p>Also no, <a href="https://infosec.space/tags/LavaRand" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>LavaRand</span></a> is just <a href="https://infosec.space/tags/pseudorandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudorandom</span></a>, because every <a href="https://infosec.space/tags/Lavalamp" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Lavalamp</span></a> has a determineable cycle of blobs it'll form...</p><p>It's just that that it'll take exact info re: the filling, geometry and used bulb to be able to reconstruct and recreate the loop.</p><p>But it's a form of <a href="https://infosec.space/tags/pseudorandomness" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudorandomness</span></a> that is considered "sufficient"... </p><p>Tho if one uses <a href="https://infosec.space/tags/CloudFlare" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>CloudFlare</span></a> they already fucked up <a href="https://infosec.space/tags/ITsec" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ITsec</span></a> so hard, they might just not use <a href="https://infosec.space/tags/SSL" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>SSL</span></a> at all... </p><p><a href="https://www.youtube.com/watch?v=1cUUfMeOijg" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">youtube.com/watch?v=1cUUfMeOij</span><span class="invisible">g</span></a> video via <span class="h-card" translate="no"><a href="https://mastodon.social/@tomscott" class="u-url mention" rel="nofollow noopener" target="_blank">@<span>tomscott</span></a></span></p>
Ana Tudor 🐯<p>The how behind this:</p><p>1⃣ Stacking multiple semi-transparent layers increases their alpha where they overlap <a href="https://css-tricks.com/adventures-in-css-semi-transparency-land/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">css-tricks.com/adventures-in-c</span><span class="invisible">ss-semi-transparency-land/</span></a></p><p>What the individual layers look like one under another below 👇</p><p>Stacking them increases the overall alpha so that, in some areas, it's > .5</p><p>A bit more on the pseudo-randomness effect given by the prime number of px `background-size` <a href="https://css-tricks.com/cicada-principle-css/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">css-tricks.com/cicada-principl</span><span class="invisible">e-css/</span></a></p><p><a href="https://mastodon.social/tags/css" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>css</span></a> <a href="https://mastodon.social/tags/alpha" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>alpha</span></a> <a href="https://mastodon.social/tags/cssGradient" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>cssGradient</span></a> <a href="https://mastodon.social/tags/gradient" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>gradient</span></a> <a href="https://mastodon.social/tags/code" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>code</span></a> <a href="https://mastodon.social/tags/coding" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>coding</span></a> <a href="https://mastodon.social/tags/frontend" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>frontend</span></a> <a href="https://mastodon.social/tags/webDev" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>webDev</span></a> <a href="https://mastodon.social/tags/webDevelopment" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>webDevelopment</span></a> <a href="https://mastodon.social/tags/cicada" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>cicada</span></a> <a href="https://mastodon.social/tags/pseudoRandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudoRandom</span></a></p>
sumanthvepa<p>This year's <a href="https://mastodon.social/tags/Turing" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Turing</span></a> Award winner is of course Avi Wigderson. I found this highly accessible talk by him on his work on randomness and pseudorandomness, which form the basis of much of cryptography and other parts of computers science. <a href="https://www.youtube.com/watch?v=Jz1UoAWD80Q" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="ellipsis">youtube.com/watch?v=Jz1UoAWD80</span><span class="invisible">Q</span></a> <a href="https://mastodon.social/tags/mathematics" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>mathematics</span></a> <a href="https://mastodon.social/tags/computationalcomplexity" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>computationalcomplexity</span></a> <a href="https://mastodon.social/tags/computerscience" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>computerscience</span></a> <a href="https://mastodon.social/tags/random" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>random</span></a> <a href="https://mastodon.social/tags/pseudorandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudorandom</span></a></p>
µP<p>Sometimes I think the <a href="https://mastodon.social/tags/10PRINT" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>10PRINT</span></a> algorithm can be used as a kind of <a href="https://mastodon.social/tags/UlamSpiral" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>UlamSpiral</span></a> to prove the quality of a <a href="https://mastodon.social/tags/PseudoRandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>PseudoRandom</span></a> number generator ...</p>
Tech News Worldwide<p>Roll the Radioactive Dice for Truly Random D&D Play <br> <br> <a href="https://hackaday.com/2022/11/02/roll-the-radioactive-dice-for-truly-random-dd-play/" rel="nofollow noopener" target="_blank"><span class="invisible">https://</span><span class="ellipsis">hackaday.com/2022/11/02/roll-t</span><span class="invisible">he-radioactive-dice-for-truly-random-dd-play/</span></a> <br> <br> <a href="https://aspiechattr.me/tags/randomnumbergenerator" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>randomnumbergenerator</span></a> <a href="https://aspiechattr.me/tags/radioactivity" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>radioactivity</span></a> <a href="https://aspiechattr.me/tags/pseudorandom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>pseudorandom</span></a> <a href="https://aspiechattr.me/tags/MiscHacks" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>MiscHacks</span></a> <a href="https://aspiechattr.me/tags/autunite" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>autunite</span></a> <a href="https://aspiechattr.me/tags/uranium" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>uranium</span></a> <a href="https://aspiechattr.me/tags/geiger" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>geiger</span></a> <a href="https://aspiechattr.me/tags/dice" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>dice</span></a> <a href="https://aspiechattr.me/tags/rng" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>rng</span></a></p>
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