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rossmum
May 18th, 2010, 09:08 AM
This isn't so much a tutorial as a collection of shit you may find useful, but I figured it probably belongs here anyway.

One of the things that consistently shits me in games is the way the weapon animations are half-arsed. Taking some artistic license is one thing, but half the time it's more a case of not enough care or effort being put into the final product. So, me being someone who gets to shoot things (including military weapons) on a regular basis, I'll drop you a few animating hints which will give you a leg up on the competition and put you in every self-respecting shooter's good books.

I'll update this periodically. In our first installment, let's look at something you see all the time but almost never see done properly (or even well): recoil.

Recoil isn't just your aim getting thrown off. It isn't just one solid boot to the shoulder or the palm. Recoil's intensity and the form it takes depends on a lot of things, and it has a pretty distinctive behaviour which you will only truly appreciate by getting out there and doing some shooting yourself. That said, I'll give you what guidance I can.

First of all, the actual recoil generated by firing. This is the 'equal and opposite reaction' to a bullet being sent hurtling downrange at a great rate of knots (well, it's not always equal - we'll get to that later). In the case of manually-operated actions, like bolt, lever, or slide-action weapons (also revolvers), this is pretty much the only recoil you get, since the only moving parts during the entire sequence of firing are the trigger, sear, and firing pin (or hammer). However, it won't leave you looking at the sky or any of that dumb shit. As a general rule, any firearm held with a proper grip will settle back near or on its original point of aim following the round clearing the muzzle. If you're limpwristing it, it might settle a bit high or off to one side; if you're trying to strangle it to death, you'll over-compensate and end up aiming low and probably off-axis as well. If you're going to incorporate displacement of view or aimpoint in a shooter with recoil, make sure it settles at least somewhere near point of aim; having to drag your weapon back on is not only unrealistic, it's also annoying as shit. Keep in mind that this is for single shots. Rapid fire is a bit different. The weapon will still settle after you cease fire, but it'll probably settle a little up and to one side (generally the side of your master hand). The more rapid the fire, the more the muzzle will climb, and the amount it does so generally increases with every subsequent round. You might land your first two rounds in almost the same spot, but the third will go high and the fourth become a hazard to low-flying aircraft (well, perhaps not, but you get my point).

When you move to self-loaders, you have a lot more to consider. It's most evident in pistols, but you'll feel it in rifles too: there's more than one impulse. That's because on top of the round being fired, there are a variety of rather heavy metal components being thrown around at considerable speeds. We'll use any given slide-type semiautomatic handgun as an example: the first thing you feel is the recoil from the shot. The pistol will kick back against your palm, as to be expected. Before it begins to settle, however, the slide (which is usually fairly robust, and is moving very rapidly) will travel rearwards until it hits a stop. The weight of the slide, the velocity at which it is moving, and the sudden deceleration as it reaches its rearmost point of travel will cause the pistol to kick back a second time. It then begins to travel forwards, again at high speed and hitting a sudden stop. In the case of heavier pistols (1911, looking at you) this produces a very noticeable forwards rocking motion (obviously any pistol of similar design does this, but not as forcefully). That's three different motions, as well as the settling. It doesn't just snap back and then forwards in a neat, smooth sequence.

The same holds true for rifles, particularly with heavy, off-balance bolt carriers. The AK action in particular is notorious for this; watch an AK-47 being fired in slow motion and you'll see the distinct movements as first the round is fired, then the bolt travels rearwards, before chambering the next round and locking up. In the AK's case the bolt is so heavy and so off-balance that the entire rifle rocks, the mag, barrel and receiver included. More precisely engineered designs (such as the AR action) barely suffer from this problem, but that's simply because the carrier is not as heavily constructed and balanced better within the rifle.

When I get around to updating this, I'll also see if I can find some good videos that illustrate what I mean. Until then, here's a video of an AK firing that amply depicts the three motions, as well as whip due to a lighter barrel and heavy bolt carrier:

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PenGuin1362
May 18th, 2010, 05:39 PM
FYI, M16's,4's 416's, anything using the design of the ar15, when the chamber is empty you must push the bolt catch (located on the left side of the lower receiver) to re-chamber a new round. the only thing the charging handle in the back is used for is if the catch is pressed without a new round in, or if you need to eject around already chambered. Also, this goes for any self-loading rifle, the operating handle is only used if all rounds have been expended and the chamber is empty, if the gun is reloaded mid clip, there's no need to re-chamber a round.

ICEE
May 18th, 2010, 07:16 PM
I like this thread.

However I think its important to note that sometimes reality doesn't look good. Sometimes its better to go with a little bit of fantasy for the sake of aesthetics or gameplay. This generally doesn't excuse animators from not simulating the bolt operation (Bad company 2) or mag release (all games ever. Fuck), but it often does dictate how its pulled off.

As for recoil... Often times its impossible to capture the proper detail of the motion with the number of frames you're given. A fully automatic weapon will generally have about 7 frames to work with. It's really too much to ask to make it look perfect, to be honest. Whats most important is that it looks acceptable when fired fully automatic (including any overlays that might come into play here) because thats how 90% of players will use it.

Geev us a break :\

PenGuin1362
May 18th, 2010, 08:54 PM
plus you can't make a barrel flex easily, especially in a production environment. you can make the gun bounce, bout it.

annihilation
May 18th, 2010, 08:59 PM
This is somewhat related. (is it really worth making a new thread?)

I've seen this being done a lot and it's getting annoying.
When you're doing walking animations please stop imitating BC2 and making your gun swing side to side.
I personally find their walking animations horrid. The pivot point is fucked up.
It's fine if you want to move your gun side to side a lot but please move it from the arms.

ICEE
May 18th, 2010, 09:59 PM
This is somewhat related. (is it really worth making a new thread?)

I've seen this being done a lot and it's getting annoying.
When you're doing walking animations please stop imitating BC2 and making your gun swing side to side.
I personally find their walking animations horrid. They make the piviot point the wrist. (or the handle, I can't really tell)
It's fine if you want to move your gun side to side a lot but please move it from the arms, not the wrist.

I believe it rotates from the stock. Where it should rotate from. Also, BC2's walking overlay rocks, imo. Its full of energy.

... then theres the sprinting animation that makes me sigh.