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cedox
01-14-2007, 11:43 AM
Found a couple posts here and some on cgtalk about tracer bullets. (Don't know what kind of 3D World issue 86's tracer tutorial was, but have to ask around about it. Our school has ordered the mag, but we haven't found that particular edition.)

Here's what I succeeded as a test: http://pelitalo.org/cedox/tracer_test.avi

My main problem would be how to make the tail taper towards the rear - the big part should be at the front, currently its exactly in the middle of the animation. Another prob is that the tracers have brighter spots here and there even if I take all texture maps off.

Would 3D World #86 help me with this? Any of you gurus have hints for me?

Oh forgot: Is there any way to generate particles in regular intervals and/or calculate collision in fractions of frames in LW9? (I read on another thread that tracer bullets actually didn't/don't fire at regular intervals, but still would like to know)

- Cedox

DMarkwick
01-14-2007, 12:41 PM
I don't know if you want a purely LW solution, or whether you don't want to spend any money on 3rd party plugins, but part of Worley's Taft collection (http://www.worley.com/taft/taft.html#toptaft) has a plugin called Tracer, made for just this sort of thing. I've never used it or even seen any product of it, but it sounds good :)

Tracers are usually placed at regular intervals, like 1 out of 5 for example. Or in the case of a machine gun, the last 20 rounds will be entirely tracers to alert the firer that he's about to run out and needs a refill.

Bog
01-14-2007, 04:37 PM
Tsk. Please. Let's not just have plugins as the universal panacea of all animation problems ;) Besides, Taft doesn't work with FPrime. Grr.

cedox, what you need to to is build your shot-shape (a teardrop form usually works OK) and use FXLink to Clone your tracer rounds to particles that're being emitted. Engage the "Align to Path" function and you're good to go.

BRIIIIP!

As to real world conditions? Tracers are usually packed in ammo loadings on an "Every-nth-round" basis - say every tenth round for belts for a SAW (firing about 600 rounds a minute) or about every 100th round (guessing) for a Vulcan cannon that belches 6,000 rounds a minute - one bright zap every second being enough to correct fire on, I guess. My numbers are not likely to be accurate, as graphics geekdom overrode my guns-n-stuff geekdom a few years back ;)

If you want me to send you a demo "bullet object" scene, I'd be happy to.

"Regular Particles" are a function of "Fixed Random" and tweaking the particle birth rate.

Virtual Mind
01-14-2007, 05:45 PM
Yep, Bog, you are right, it is 1/100 for the Vulcan. Insanely fast gun.

BigHache
01-14-2007, 06:49 PM
My fav is project Metal Storm that boasts a sweet 1 million rounds/min. through 36 barrels. You know, graphics geekdom and guns geekdom can be combined...

lesterfoster
01-14-2007, 08:52 PM
My fav is project Metal Storm that boasts a sweet 1 million rounds/min. through 36 barrels. You know, graphics geekdom and guns geekdom can be combined...
Wow. Are you talking about this link??

Http://www.metacafe.com/watch/239653/metal_storm_weapon_system/

Or perhaps this ling??
Http://www.popularmechanics.com/technology/military_law/1281426.html

You sed 1 million rounds per minute. At first I did not believe you. But now I do.


And that video about the Metal Storm Machine Gun. Was fantastic. I would like to know what they used to make that video.

cedox
01-14-2007, 11:01 PM
Thanks guys! I love you :) I'll try Bog's geometry approach. And thanks for the real-world tracer infos. I read from a similar thread that in ww2 at least somewhere in world they just grabbed a bunch of tracer ammo and hit them in the mag :-)

The problem is still the randomness of the emitter. Maybe I'll just do a keyframe animation and apply some gravity and drag. Thanks a bunch to all of you and nice link on the Metal Storm.

- Cedox

Bog
01-15-2007, 12:34 AM
Yeah, the randomness can be a pain. I'm sure there used to be a way to get regular emission of particles rather than the random type. I suppose you could set your emitter to Event driven emission, and "blip" the emitter with your Event, but that really feels like too much of a kludge. If you follow the Imaginetix link in my .sig, there's a section in my showreel which shows geometric-style gunfire - it's quite effective, but again it's a bit uneven.

The Metalstorm thing is very funky indeed - doesn't seem to be too much call for the like in today's asymmetrical battlefield, but if the aliens invade it could be darn handy. Then again, it reminds me a lot of the LBX-20 for those who played Mechwarrior...

Let us know how you get on, cedox!

cedox
01-15-2007, 12:39 AM
Got it almost working with geometry. Antialiasing is giving me the creeps though

Here're the test renders:
http://pelitalo.org/cedox/tracer_test2.avi without antialiasing
http://pelitalo.org/cedox/tracer_test3.avi with antialiasing

The antialiased seems to go semi-transparent and lose luminosity a lot. I'd still like to use antialiasing. There are no transparency settings in the tracer object itself and glow is off atm.

I'll be probably using vector blur if it works with particles.

- Cedox

Bog
01-15-2007, 12:44 AM
cedox, if you try adding a lozenge shape (just use the Capsule tool at low complexity) in the "head" of the semi-transparent teardrop, and make the lozenge uber-bright (say, 300% luminosity), then when you put (say) seven passes of anti-A on it with Dithered motion blur, it should look pretty tolerable.

Heh. AA on your AA... ;)

cedox
01-15-2007, 01:03 AM
Thanks, uber luminosity helped :D

Lol, guess what I found when I was googling for lightwave aa gun tutorial :P

- Cedox

McFilms
01-15-2007, 01:53 AM
Tsk. Please. Let's not just have plugins as the universal panacea of all animation problems ;) Besides, Taft doesn't work with FPrime. Grr.

cedox, what you need to to is build your shot-shape (a teardrop form usually works OK) and use FXLink to Clone your tracer rounds to particles that're being emitted. Engage the "Align to Path" function and you're good to go.

BRIIIIP!

As to real world conditions? Tracers are usually packed in ammo loadings on an "Every-nth-round" basis - say every tenth round for belts for a SAW (firing about 600 rounds a minute) or about every 100th round (guessing) for a Vulcan cannon that belches 6,000 rounds a minute - one bright zap every second being enough to correct fire on, I guess. My numbers are not likely to be accurate, as graphics geekdom overrode my guns-n-stuff geekdom a few years back ;)

If you want me to send you a demo "bullet object" scene, I'd be happy to.

"Regular Particles" are a function of "Fixed Random" and tweaking the particle birth rate.

I don't know about anyone else, but I would love to check a sample scene of it for sure.

P.S.
I agree on the plugin issues. The more I look through the manual(s), the more I find that, if imagination is employed at 300%, you can usually figure out a way to use tools for more than just their intended purposes.
For myself, I sortta leaped right into tasking myself on my own things without allowing experimental time. (THANK GOD FOR THIS BOARD AND ITS INHABITANTS!!!)

cedox
01-15-2007, 02:50 AM
http://pelitalo.org/cedox/tracer_test4.avi that's the final I managed to make. Still used teardrop instead of lozenge shape though. Strange multiplying effect happening that is noticeable to eye in the animation if just barely. It adds some feeling to the scene maybe. Might be blur settings, have to check them.

- Cedox

p.s. You're absolutely right McFilms