BFG Question

[Terra-jin]

Hi people. I've read the BFG FAQ all through, but I still can't grasp how the traces work.

If you have a line of sight with the explosion, the FAQ says there are 40 traces which are shot at various directions from the cone. Do these traces work like invisible bullets or something? And from where do these traces originate, the player or the explosion?

Also, some say that the traces do 49-87 damage each, and some say 16-128. Which is right?

[Donce]

The traces are like 'laser beams' beaming away from the player towards the 'azimuth' of the explosion. If a monster (or an opponent in DM) is hit by a trace, he gets damage. The nearer is the target, the more traces hit because they are densier. Here I have a question of my own - does the monster radius matter here? That is, will a mancubus take more damage than a revenant at the same distance?

[Terra-jin]

I guess, since the traces are distributed across an angle of 90 degrees and the Manc is wider than the Revenant, the Mancubus will be hit by more traces than the Revenant...

The source code says the traces do 16-128 damage, so nevermind my earlier question :) I still wonder where people got that 49-87 value, though.

[fraggle]

Terra-jin said:

Do these traces work like invisible bullets or something?

Yes.

And from where do these traces originate, the player or the explosion?

The player. The cone extends from the player in the direction they fired the BFG.

Also, some say that the traces do 49-87 damage each, and some say 16-128. Which is right?

The Doom source says 16-128 damage per trace, with a gaussian (bell-curve) distribution.

[Fredrik]

No, the correct range (for vanilla Doom) is 49-87.

This is because the damage is calculated by adding up successive outputs from the random number generator. With a perfect random number generator you could get all values from 16 to 128, but Doom's only has 256 different states. If you test all 256 possibilities, you get a minimum of 49 and a maximum of 87.

Here's the distribution:

49 1
50 2
51 1
52 3
53 3
54 7
55 3
56 8
57 7
58 4
59 4
60 12
61 11
62 6
63 7
64 10
65 14
66 16
67 9
68 12
69 13
70 12
71 13
72 17
73 12
74 11
75 6
76 3
77 4
78 1
79 6
80 5
81 4
82 3
83 3
85 2
87 1