How wide is a "line", i.e. Lightning Bolt?

[allenw]

One of the really annoying things about the new "line" description is that it's only of use if you are, in fact, using a battlemat or similar graphing surface. If you aren't, and just want to know whether a Lightning Bolt can affect two people defined as standing 5' apart (and not one behind the other), you have to go through heroic feats of reverse engineering to answer the question. (The answer appears to be "yes," by the way, for those of you keeping score at home. Note that in 3.0, a Lightning Bolt could be cast as either 5' wide or 10' wide (though with different lengths), so this isn't an arbitrary increase in the spell's power. It's just horribly murky rules-writing. ).

Even though it can (and often will) affect two adjacent squares, I've decided that the designer's intent is that a 3.5 Lightning Bolt is "really" 5' wide. We know it's not wider than that, because if you angle your "line" right, you can affect only a column 1 square wide, with the Bolt filling up that line of squares (simulating the 3.0 ability to make the bolt 5' wide). However, most of the time, the width of the Bolt will take up part of two adjacent squares at the same time, with the result that creatures in both squares are affected (simulating the 3.0 10' bolt).

Granted, it might be more "realistic" if someone in the "center" of the bolt (all of the bolt is being sent through their 5' square) has a harder time saving for half-damage than someone whose square is getting just half the bolt, but that doesn't bother me too much; if it did, I could just assume that even in the "center" there are gaps and forks in the effect (which makes sense for a fantasy lightning-bolt), so that the area is still only partially "filled".

 

[Jens]

Jhyrryl,

I agree that things should be kept simple. But why do you *have* to draw lines between the squares? Why not take a chess board? That 'definition' of a grid of squares should be as good as drawing the boundaries between the squares. Now, it seems to me that your argument above relies on the squares being bounded and that the borders are shared to the degree that it cannot be made using a chess board. [Here, I would have liked to put a small bitmap I made, but how to display it? I will try putting it in an attachment.]

Also you say that "The definitions of squares 1 and 2 share a common line segment that runs between points B and E. Because all the points along that segment exist in the set of points that define the area of both squares 1 and 2, a spell's line effect that is designated to run along such a segment, must affect both squares." The first part I agree with, that's the implication of the definition of squares that you use. But whether "a spell's line effect that is designated to run along such a segment, must affect both squares" depends completely on what the rules say, and in one place it says it does and in another it says it doesn't.

Ah, well. I guess it doesn't matter that much anyway.

One of the really annoying things about the new "line" description is that it's only of use if you are, in fact, using a battlemat or similar graphing surface.

Agreed

 

[Vaxalon]

Mathematics has a real hard time defining things that butt up against each other but don't overlap AT ALL.

The real world does, too... there's ALWAYS a space in between two objects where there's nothing.

 

[JLXC]

One of the really annoying things about the new "line" description is that it's only of use if you are, in fact, using a battlemat or similar graphing surface. If you aren't, and just want to know whether a Lightning Bolt can affect two people defined as standing 5' apart (and not one behind the other), you have to go through heroic feats of reverse engineering to answer the question. (The answer appears to be "yes," by the way, for those of you keeping score at home. Note that in 3.0, a Lightning Bolt could be cast as either 5' wide or 10' wide (though with different lengths), so this isn't an arbitrary increase in the spell's power. It's just horribly murky rules-writing. ).

Could I agree more? NO! This is so on the money. Affects a line indeed!