Comments on: 2D Line of Sight?

By: Juuso

Juuso — Sun, 25 Apr 2010 14:38:07 +0000

@Joonas: That’s one cool avatar. O:)

…and, I might look something simpler – such as vision check. I think it’ll work just fine for me. Thanks.

By: Joonas

Joonas — Sun, 25 Apr 2010 07:31:58 +0000

You can likely use the A* algorithm. http://en.wikipedia.org/wiki/A*_search_algorithm

I wrestled with this some years ago when trying to put together a tile-based stealth title on BlitzBasic. What I came up with after brushing up my math skills for days was basically the A* algorithm. It worked for me, but I wasn’t using it in realtime.

By: Juuso

Juuso — Fri, 23 Apr 2010 17:55:19 +0000

@Andreas: yeh, thanks. Like Jake said… it was not in my line of sight. I was thinking something way too complex ^_^

@shagwana: I checked that one, thanks.

@tonic: eh, I’d rather keep it so that somebody else tackles this for me :P

By: Jake Birkett

Jake Birkett — Fri, 23 Apr 2010 01:35:41 +0000

The solution was not in your line of sight.

By: tonic

tonic — Thu, 22 Apr 2010 19:33:07 +0000

Do yourself a favor and buy “Real-Time Collision Detection” by Christer Ericson, you’ll find lot of usable stuff there, including relevant stuff for problems like this (e.g. tile traversal). Every game programmer should own it. :)
http://bit.ly/RTCDbook

By: shagwana

shagwana — Thu, 22 Apr 2010 16:54:30 +0000

http://www.blitzbasic.com/codearcs/codearcs.php?code=148

This is a code snippet I posted for blitz 3d a long time ago, using a Bresenham line algo. Should’t be to much work to get it working in max, it lets you trace the line in controlled steps rather then doing it all at once.

By: Andreas

Andreas — Thu, 22 Apr 2010 07:25:02 +0000

:) glad I could help. Sometimes you get blind to the simple solution.

By: Juuso

Juuso — Thu, 22 Apr 2010 06:39:16 +0000

That is bloody genius. How come I didn’t think of that.

Maybe I should do (1) less 2d math research when tired and (2) spend more time listening to people who know. :)

By: Andreas

Andreas — Thu, 22 Apr 2010 05:31:14 +0000

He he ok, well have a line for the guards line of sight, check that line against all gameobjects bounding box. If the ninja is the closest one it´s visible.

By: Juuso

Juuso — Thu, 22 Apr 2010 04:00:44 +0000

yeh, but besides direction there could be wall/objects between them which makes ninjaInSight = false :)