Path: chuka.playstation.co.uk!news
From: "Rad" <rad@cyberdude.com>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: 2d collision bounding box...
Date: Mon, 7 Dec 1998 23:44:23 -0000
Organization: PlayStation Net Yaroze (SCEE)
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Message-ID: <74hp72$8bc3@chuka.playstation.co.uk>
References: <366C2C7E.75028A95@club-internet.fr>
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Hi Chris,

What you are looking for is pixel-perfect collision detection rather than
the bounding box method.
However even though this method is much more accurate it's also a lot slower
because instead of testing each rectangle for collision you have to test
each pixel instead (and there a lot more pixels!).

I'll get around to coding some collision detection during the christmas
holidays so untill then I can't really help you out, but my suggestion would
be to check out the source code to James Shaughnessy's excellent Gravitation
(http://www.netyaroze-europe.com/~shaughnj/ftp/gravsrc.zip) which uses
pixel-perfect collision detection.

Hope this helps,

Rad.
rad@cyberdude.com
http://www.netyaroze-europe.com/~radpsx


cros wrote in message <366C2C7E.75028A95@club-internet.fr>...
>hi.
>Ok,when i want to detect collision between sprites i use bounding boxes
>rectangle following my sprite.
>In my case, that is:
>
>i have a ship(i make a space invaders for training me to C ...)like
>this(approximatively!!):
>
>                i
>               iiii
>          i   iiiiiii   i                <----This is the ship(fabulous
>isn't it?)
>          iiiiiiiiiiiiiii
>            iii     iii
>
>
>i have a super-laser-bullet like this:
>
>   the laser--->       0                 <----(i can believe my eyes!
>this laser-bullet is so terrific)
>
>
>How can i  make this collision operations between this two objects?:
>
>
>
>
>
>                i
>               iiii   0
>          i   iiiiiii   i   ----->here no collision
>          iiiiiiiiiiiiiii
>            iii     iii
>
>
>                 i
>               iiii
>          i   iiiii0   i   ----->here, there is collision
>          iiiiiiiiiiiiiii
>            iii     iii
>
>Like you can see on my terrible ASCII graphics, the bounding box method
>don't works, how can i do?
>
>Chris
>