BF2 metre size

[nedlands1]

Ive always ben told to never quote to more sf's than I can confidently say a value is, eg if all data is to 2sf then never quote to 4sf, although 3 is acceptable when the value is roughly on the line between 2 different values, like 12.5. I've just gotten used to using them like that.


Interesting method. Although if there is a modifier I think it is also useful to find the apparent value, sen on a public server. And I dont believe that bullets are affected by gravity as otherwise it is possible to have parabolic bullet drop instead of the current linear drop. It would be possible to get the bullet to go through a zero point at 300m based on initial angle AND gravity. Still though, the fact that it is close to the engines value of g is quite strange/impressive, I just havnt figured out which yet.

Try get a video of the bullet moving through the air at walking speed to see which is the correct bullet drop, if it is linear you should see it go in a straight line, defying gravity all he way to the wall, but if it is parabolic it will hit the floor.


Calculus is surprisingly easy though, that could just be because I have been doing it for over a year now very frequently because of my Further Maths course.

The bullets follow a parabolic path. Fire off a light AT shot or a grenade from an UGL upwards and watch that symmetrical curvature . What I have been fiddling with the the drag modifier which, if I am correct, decelerates the projectiles proportionally to their velocity. This results in a path very similar to true bullets.

[nedlands1]

but these projectiles are some of the few which I am certain follow parabolic paths, its the bullets fired from rifles, carbines and pistols I am not sure of.

They are the same. The only difference is the scale. If you like I can instruct you in the ways of notepad so you can do your own empirical testing.

[nedlands1]

Really? You mean the devs have been lying to us about not being able to make realistic bullet drop? Why devs? Why?

Using the conventional methods they can't account for the slowing down of projectiles due to drag forces. There is however a drag modifier which should, in theory, allow for more precise bullet drop. I believe that it is also dependent on a mass modifier. I suspect that drag is probably calculated in-game as many times as possible per second for as long as the bullet is in flight. It would appear from some of my simple experimentations that the drag force is proportional to instantaneous velocity which leads to observations of a maximum range for projectiles. I also checked to see that these "drag effected" projectiles weren't under the influence of some timer influenced decay thingie.

[nedlands1]

I believe you could achieve a zero by moving the sight picture slightly down. This however, as I have been told, is no easy undertaking.

EDIT: I assume the reason you would want to change the angle is for a zeroing purpose?

[Masaq]

You guys are impressive. Impressively endowed with free time, mathematical brains or tomfoolery, I can't decide, but it's impressive none the less

You think you'll be able to make this stuff practical and applicable? I mean it's one thing to demonstrate parabolic curves with a bullet at walking speed, but the mod kinda requires rounds to be a tad quicker It hold up at higher speeds?

[nedlands1]

You guys are impressive. Impressively endowed with free time, mathematical brains or tomfoolery, I can't decide, but it's impressive none the less

You think you'll be able to make this stuff practical and applicable? I mean it's one thing to demonstrate parabolic curves with a bullet at walking speed, but the mod kinda requires rounds to be a tad quicker It hold up at higher speeds?

All these parabolic curves work at high speed. These are not approximations. These trajectories follow the conventional effects of traveling bodies under the influence of gravity in a vacuum(no drag effects). In order to somewhat realistically model the drag effects the "drag" modifier along with the "mass" modifier could be used. These trajectories would therefore not be parabolic as the velocity of a round decays after the round has left the barrel. Currently I don't know how BF2's drag is calculated so if you want to accurately model bullets you would need a trial and error approach to approximate the ballistics data you have.

With regards to zeroing the weapons, I believe a number of things must be done. Firstly the ballistics must be at an acceptable level(wouldn't want to have to re-zero the weapon when it is decided that the ballistics need to be changed). Secondly, the height of the sights needs to be changed so it is actually above the barrel. Thirdly, the angle between the scope and the barrel needs to be changed so it is appropriately tilted to the the zero.

[nedlands1]

But, we are zeroing to 300 and 600 metres, which is not far over this, people dont render for much further in-game either, so if we try the harder stuff and cant do it (highly unlikely) then the simpler stuff will give an appropriate approximation.

We should probably zero weapons at a much closer range, say 25-100m. In terms of ballistics, although the engagement ranges are short, the effects of drag forces are should be noticeable at the maximum effective ranges. Looking at the drop vs range graph of the rounds that are used in SVD's, when the range is < 150m, a parabolic path is a damn good approximation. You could even approximate it for further ranges. For the pistols, SMG's, PDW, shotguns and possibly unscoped rifles, not bothering with the drag modifier will probably do. As for the scoped rifles, MG's and cannon, drag would probably need to be modelled.

[nedlands1]

If we model drag for any rifle then it only makes sense that we copy and paste it onto other rifles of the same model, so all M16s will have the same model for ballistics, deviation included, the extra accuracy comes from the scope.

If we decide on a nerfed range for any rifle then all should be affected, eg zero to 80% of actual range. However with bigger maps I would prefer a 100% zero-range.

Just to get this clear, you don't zero your rifle to your maximum range. The zero range is the range in which the rounds will land where you aim. So if I zero a rifle to 200m, aim and shoot a target halfway down then the rounds will land halfway down the target(assuming the same conditions as when the zero was taken).

EDIT: For sure use the same data for the unscoped variants of the scoped rifles. What I am talking about is the rifles which don't have a scoped variant (eg the SKS or AK-47).

[nedlands1]

yeah the zero range is where the bullet hits where you aim, as shown here:


If you then shot a target at half that distance the bullet would land a little abouve centre, as it arcs upwards.

And no, you dont zero at the max. effective range, for the M-16 the max. effective range is about 550m, yet in PR they are supposed to be zeroed to 300m, about half the max. range. This is to allow you to shoot a little further than the zero point accurately.

I am extremely skeptical about the so called "zeroed" rifles in PR. If anything they are zeroed to 0 m.

[nedlands1]

HAHAHA

yeah but that is because no one has done the balistics properly yet...

They are approximated to actual zeros of 300m for assault rifles, 100 for carbines and 600 for all sniper rifles. Or so i've heard...

We should try to keep these values when we re-do the balistics, its easy to understand.

Yeah I don't believe a word of it. When I shoot my M82A1 sniper rifle ingame at a target 600m away the round will land halfway down the black notch thing. If it truely was zeroed to 600m then it would land dead centre. The assault rifles/battle rifles/carbines have rounds which come out directly from the centre of the screen which coincides with the top of the post or center of the crosshair. Unless the round travels without any gravitational effects until it reaches the zero range, which I highly doubt due to my own testing and no indication of anything like that in the .tweak files, then they are not zeroed to theses ranges specified.