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Verlon
05-20-2004, 07:40 AM
So I want to destroy an airplane in LW8, and it is not behaving as I wish.

I set up the plane and propeller (spins briefly then dies).

I add particles effects for smoke coming off the engine.

I add wind so the smoke moves toward the back of the plane as it should.

All is well so far.

Now I add a collision sphere and have it drop from above (I want the plane to fall apart kind of comic-book like, not a real explosion). Then I set the properties of the plane to respond to the collision sphere. I make certain that the collision sphere and the plane are in the same group with each other, but in a different group than the wind and the particles.

1. The wind blows my airplane away so that the collision sphere misses it entirely.

I add a keyframe to give my plane forward motion to counteract the wind.

2. No good, the plane ignores the keyframe and blows away in the wind.

I delete the wind (with the intent of fixing the particles later), but add the prop to the collision affected.

3. The prop no longer spins, regardless of how I try to keyframe it.

Finally, I can't seem to add gravity so the pieces fall without having the plane come apart at frame 1 instead of 150 or so.

While I am managing to work around these problems, I would like to understand what is happening for future work.

lasvideo
05-20-2004, 09:00 AM
From my limited expereince with LW8 dynamics I can address the
wind/smoke/plane issue. If you create a group of the wind and the particles that should prevent the wind from affecting the plane.

Verlon
05-20-2004, 09:30 AM
I said that I made sure that wind and particles are in a different group than plane and collision sphere.

Wind and particles group = Breeze
Plane and Collision sphere = crash.

My plane still blows away.

Thanks for responding though.

MiniFireDragon
05-20-2004, 11:36 AM
I been tinkering with Dynamics myself and have the same gravity problem. What I did was the falling brick effect. No matter if u set gravity by itself or in the Dynamics sheet, it is ALWAYS effected by gravity. Kinda sucks cause my bricks start moving before any contact.

What U will have to do is have the collision object hit the other objects at the rate of which you want the objects to move.

Verlon
05-23-2004, 07:03 AM
I am guessing the wind and gravity are set like that because they are frequently global events. Still, it would be nice to have a "global" group (prehaps the default group) for things you wanted global, and all other group restricted.


Verlon

digitalsnake
05-23-2004, 09:38 AM
Originally posted by Verlon
I am guessing the wind and gravity are set like that because they are frequently global events. Still, it would be nice to have a "global" group (prehaps the default group) for things you wanted global, and all other group restricted.


Verlon

That's the way it works allready, the default group is global.

hairy_llama
05-23-2004, 10:15 AM
Set your hard dynamics to "start by collision" that way your plane will stay intact untill it gets hit.