hyphz
Level: Delver
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Registered: 01-02-2006
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Can anyone think of or know of a good LOS algorithm for a tile-based game?

At the moment I'm doing it by using Bresenham linedraw from the source to the target and stopping on an encountered obstacle, but that sometimes introduces problems when Bresenham shifts coordinate at an unusual position.

I'm used to doing things like "tracing four corners" in tabletop grid-based games but that isn't so viable to do in a tile-based computer game because there is no coordinate system more detailed than the grid.

Briareos
Level: Smitemaster

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Can't you just do the Bresenham in half-tile increments, i.e. treat each tile as a 2x2 square? Or do you mean the case when the line waltzes diagonally across the corner of a tile?

np: Mouse On Mars - Froschroom (Rost Pocks)

____________________________
"I'm not anti-anything, I'm anti-everything, it fits better." - Sole
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Pekka
Level: Smiter
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The Roguebasin Wiki lists and discusses several Field of Vision techniques. You'll probably find good ideas to try there.

http://roguebasin.roguelikedevelopment.org/index.php/Category:FOV