Fast Inverse Square Root Function - Seems to have been created for Quake | Hacker News Reader

Fast Inverse Square Root Function - Seems to have been created for Quake

scribd.com

15 pointsdangoldin15 comments

The PDF: http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf

It is at the point now where I click on the comments for every scribd.com story to see if someone has pasted in the original pdf url. Never fails.

I've noticed everyone likes the PDF version. It's trivial to add it as a comment since I have it copied in the clipboard from creating the submission - it's my standard practice now.

Sure fire way to get karma it seems.

Definitely. After a few hundred it doesn't really matter though.

Then why not submit the direct PDF link in the first place? Or is it a 'helpful' news.yc antifeature?

(PDF readers actually load faster than scribed, provided you aren't using the vanilla Adobe one with all the plugins turned on.)

It's a "helpful" feature. All PDF links are auto converted to scribd.

It would be more useful if the original hyperlink to a PDF file was preserved and a hyperlink to scribd was also presented. This would also eliminate a problem with duplicate hyperlink suppression.

As most readers here already know, scribd is a YCombinator startup, so it's a useful feature for news.YC to have.

The history of this function: http://www.beyond3d.com/content/articles/8/

Finding the original author of the function (Greg Walsh): http://www.beyond3d.com/content/articles/15/

If you just want the big picture, this link is easier to skim:

http://betterexplained.com/articles/understanding-quakes-fas...

No. The "inverse square root function" is the "square function."

What you want is a function that gives the inverse of a square root.

Mathematical terminology sucks.

I was thinking the same thing.

  int inverse_square_root(int x) { return x * x; } // patent pending

great... now we can have all the posts that repeat every 3 months on programming.reddit repeat here too! YAY for signal:noise.

Just don't upvote the submission. If it's a major dupe, it will get off the front page very quickly.

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