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georgefox
11-04-2009, 12:22 AM
I'm kinda struggling with creating realistic bullet hits and impacts. My goal is to get bullet hits with dust and also lots of rock/debris of different sizes and shapes with the majority being smaller.I figure I need to do this with maya particles (with instanced geometry or something) and possibly fluids (for dust).

Has anyone done something like this or knows how to?

Thanks,

George Fox

Wick3dParticle
11-04-2009, 12:37 AM
Hello George,

I would go about doing this using instanced particles (like you mentioned) and sprites for the dust hits. Using sprites in many cases can be a great alternative to using fluids where you aren't really in need for a thick volumetric smoke. Another option could be comping in a 2d element which is pretty fast and easy. For the holes, I would just use cards.
It really depends on the project and its needs.

Hope that helps,

~Ilan

georgefox
11-04-2009, 12:51 AM
Hello George,

I would go about doing this using instanced particles (like you mentioned) and sprites for the dust hits. Using sprites in many cases can be a great alternative to using fluids where you aren't really in need for a thick volumetric smoke. Another option could be comping in a 2d element which is pretty fast and easy. For the holes, I would just use cards.
It really depends on the project and its needs.

Hope that helps,

~Ilan

Thanks :)

For the actual particles i am having a heck of a time trying to get them to "move" realistically with a lot of force. I think I need to use Fields for it I'm just not sure which is best for this.
Oh and is there a script or something to generate rocks and debris


BTW: I am using this mainly for compositing against live action.

MugenTsukiyomi
11-04-2009, 01:39 AM
This might help:http://gnomonology.com/group/8

apoc519
11-04-2009, 01:46 AM
set your bulllets to collide with whatever they are supposed to be hitting. Then in the particles menu, create a new particle collision event and have it emit a few particles on collision.

That will create a new particle shape that you can instance some debris to.
You could create another collision event for dust or another that leaves a card with a bullet hole texture on it

thats the most automated way to do it but it doesnt give you a lot of control over where the bullets hit or when.

georgefox
11-04-2009, 01:57 AM
Thanks Again

I've already seen the Gnomon video. Not bad but not nearly realistic enough; think more like Saving Private Ryan or Black Hawk Down
I was more referring to the actual debris tho like how to generate lots and lots of diferent debris to instance on to my particles

Calibrix
11-04-2009, 06:55 PM
You are correct in you assumption that you need fields. The feel of you debris will depend on the kind of shot you are trying to achieve. I'm are these bullet impacts a slow-mo type effect or are they playing at realtime as part of a scene? This will affect how you use the fields.

You may way to make two particle fields: one for the larger debris and one for the smaller pieces. Larger bits will act heavier than the smaller pieces. I would suggest setting up you large pieces first, since there are less of them -- simple is always better. As a start I usually add gravity, drag and turbulence to a particle sim. Gravity for obvious reasons, drag to add air resistance, and turbulence for a more random looking effect.

Once you have dialed the larger bits the way you like them, go back and add the smaller ones. Hook the smaller bits up to the same fields and set their conserve value lower. This makes takes the edge off their velocity, making them feel more "floaty." You'll have to play with this setting.

Good luck

georgefox
11-05-2009, 08:14 PM
You are correct in you assumption that you need fields. The feel of you debris will depend on the kind of shot you are trying to achieve. I'm are these bullet impacts a slow-mo type effect or are they playing at realtime as part of a scene? This will affect how you use the fields.

You may way to make two particle fields: one for the larger debris and one for the smaller pieces. Larger bits will act heavier than the smaller pieces. I would suggest setting up you large pieces first, since there are less of them -- simple is always better. As a start I usually add gravity, drag and turbulence to a particle sim. Gravity for obvious reasons, drag to add air resistance, and turbulence for a more random looking effect.

Once you have dialed the larger bits the way you like them, go back and add the smaller ones. Hook the smaller bits up to the same fields and set their conserve value lower. This makes takes the edge off their velocity, making them feel more "floaty." You'll have to play with this setting.

Good luck

Thanks that really helps.

Oh and its real time. A lot of the footage will be done handheld with a high shutter and may be under-cranked

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