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    Carmack On Shadows


    Linguica

    Lead id programmer John Carmack updated his .plan yesterday with a small blurb about a new NVidia white paper on the subject of shadow volume rendering, which is of course one of the cornerstones of the Doom 3 engine. Also on the site is a small document, dating from May 2000, detailing previously unpublished correspondence with Carmack where he talks about his forays into shadow volume rendering. Here's a little blurb to make your head hurt:

    The next iteration involved attempting to "preload" the standard stencil shadow algorithm by the number of clipped away planes. I first drew the shadow volumes with depth test disabled, incrementing for back sides and decrementing for front sides. This finishes with a positive value in the stencil buffer for each plane that is clipped away at the view plane. The normal depth tested shadow volume is drawn next, with the change polarity reversed, decrementing for back sides and incrementing for front sides. The areas not equal to the initial clear value are in shadow.

    Ow, I need to go lie down.

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    You get my sig plus ROFL times 15.
    That equals 1997+(1815612*15) = 272136177 points.
    But I still think Carmack was talking about programming planes that drop ammo clips :)

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    I should have read this article more closely... Carmack's incrementing backsides and decrementing front sides.
    If you thought about that for a while, you'd start thinking Carmack was gay.

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    Originally posted by Virgil
    Here's a link to a picture of the bug:

    http://www.geocities.com/Virgil_32_0/pics1/dw_1.bmp

    As you can see, most of the text is either black (the color of the backgound) or illegible.

    Netscape 4.7's CSS implementation is utterly utterly broken. Use a decent browser such as IE or mozilla which actually conforms to the CSS specification.

    I use Netscape 4.7 (to avoid some of the browser privacy issues IE brings up...)

    What privacy issues? Netscape was revealed last week to contain spyware..

    Seriously, I am fed up hearing about people who complain that pages dont display in netscape properly. Take a hint. YOUR BROWSER IS BROKEN.

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    I didn't understand at all HOW Carmack did it, but I think he made real-time shadows possible on GeForce1 and 2 cards. Which is quite an impressive accomplishment. The good news is that Doom3 will not look like shit if you have anything less then a GeForce3.

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    Doesn't my wonderful (not) V3 2000 count? With it's glorious blob shadows? :D

    Anyway, I'll see you later Arn in #wirehead for a good 'sawing ok?

    As for carmack's thoughts I actually started to understand it right after the bit that gave Linguica a headache.

    Not really that hard to understand nowadays...

    Oh yeah, I did make a BBC Acorn Model B game a long long time ago so yeah, I filled that dream :)

    Now I want to do it again, after I finish my...assigned tasks.

    Seeya Arn,

    Your fellow UK'er 'sawing fanatic,

    Yickle.

    P.S. Hope they get out the patch soon, need that Doom SSG fix...weeee (ok, I admit, I'm tired...I'm going now...)

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