[reitzensteinm]

I wasn't going to say anything, but you're being upmodded like crazy, so...

It's a complete apples to oranges comparison. Scribd is performing quite complex logic with an emphasis on correctness not speed. I feel like you're dismissing an interesting article for the sake of an amusing one liner, and that's pretty much the antithesis of HN.

[CamperBob]

I feel like you're dismissing an interesting article for the sake of an amusing one liner, and that's pretty much the antithesis of HN.

It is a nicely-written and illustrated article, but it describes a problem that hasn't been considered 'interesting' for decades and can, in any case, be tackled with a caching scheme. Why would they need to run the same intersection logic over and over, when there's only a finite number of glyphs to render in any given document?

[matthiaskramm]

> but it describes a problem that hasn't been considered 'interesting' for decades

Actually, polygon operations on grids is still an active research area, with the latest papers on the topic less than two weeks old: http://www.sci.utah.edu/socg2010agenda.html

> Why would they need to run the same intersection logic over and over [...]?

We usually don't. It basically depends on the context in which the glyphs appear on the page. For a standard, say, LaTeX document consisting of mostly text and without weird graphic operations taking place around or on top of the text, a given glyph is just processed once.