View Full Version : How - automated gun mechanics ?

04 April 2008, 10:30 AM
Hey there,

I have problems setting up a flow, that simulates a simple blowback gun effect in particle flow.

I have the two parts of the bullet, which are instanced objects, and the slide, which is instanced, too.

What I have so far is, that the bullets move into the slide, hit a collision object, so that they stop for a few frames, and then are released on the other side of the slide.

My problem now is, to get the event (Bullet hit the collision object) into another particle flow, as a trigger. So that the slide, which is also an instanced particle, moves forward, maybe collides with a dummy, too, and then moves back again, collides with a dummy, and stops.
The projectile should be fired, as the slide moved forward.

04 April 2008, 02:15 PM
Hi there.
I think you should animate movment of the slide and then instace it like projectile and shell.
Just turn on "Animated shape" on it's Shape Instance, and place it where it should be.
I have attached my flow and preview of result.
I wonder if i could make a video tutorial out of this idea ? Becouse i have few cool ideas that i could add to it, like trigger, muzzle flash etc.

04 April 2008, 02:42 PM
might have this wrong ......
can you just animate the slide moving then instance that with the animation set to the amount of time in the event

04 April 2008, 05:53 PM
The way I have done this in the past is to lock your bullets to the belt and hand animate the belt moving into the gun (include the pause for the firing). Then inside the gun, have a collision object linked to the slide, so that when it moves back, it triggers the particle into a new event to fly out.

04 April 2008, 02:00 AM
From my experience it's relatively straightforward to automate muzzle blast, projectile and ejected brass from a single particle event, but integrating that with the cycling action of the weapon is a bit more involved. What's worked for me is to separate the action motion to a reaction manager that generates a value and then reference that value in your Birth Event - so if the action cycles, a particle will be birthed and the process initiated. I showed how to do this in the Combat Effects Animation master class back in 2005....hmm, seems like yesterday ;)

05 May 2008, 04:24 AM
Where can you get hold of the old Master Class CD's and other Siggraph CD's if you aren't able to attend? I've looked around for that stuff and can't find it? I'd love a copy of your Class.

Also is the
"separate the action motion to a reaction manager that generates a value and then reference that value in your Birth Event"
technique more reliable than using deflectors as a trigger?

I've automated several machine guns, in particular a ship mounted Vulcan. In the viewport all my particles show up but come render time all the particles (projectiles) don't render and just mysteriously disappear somewhere into the void that is 3ds Max.

05 May 2008, 09:14 AM
Combat effects sounds great, what else did you show? And is it available on DVD or something?

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05 May 2008, 09:14 AM
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