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Particle calculation between frames/fields

Posted: Mon, 22nd Mar 2010, 9:03pm

Post 1 of 7

Helge

Force: 1600 | Joined: 16th Jan 2010 | Posts: 116

VisionLab User PhotoKey 3 User Windows User

Gold Member

Good evening everyone,

I have been doing some experiments with the particle engine lately. Right now I'm trying to set up a very fast moving particle emitter. Everything went quite smoothly but now I'm having the a problem which troubled me with other particle engines before.

For each frame/field a bunch of particles is generated. Because of the fast moving emitter there are gaps between these spots. That is why my trail of smoke looks like a rope of pearls wink



Of course I could go with a slower emitter, render more images, throw away the ones I don't need and simply use the images left after that - but this seems to be a little inefficient to me.

Is there a way to make VisionLab calculate particles/particle positions between frames/fields? I think calculating the positions without rendering them to an actual image wouldn't take that much time. (In fact it should be much faster than anything I can think of right now.) Any ideas?

Thanks for helping me think wink

Kind regards,
Helge
Posted: Mon, 22nd Mar 2010, 10:13pm

Post 2 of 7

Fxhome Dude

Force: 996 | Joined: 1st Jun 2009 | Posts: 927

CompositeLab Pro User FXpreset Maker FXhome Movie Maker Windows User

Gold Member

Can increase the numbers of particles (particle rate)? That should help fill out the gaps. Even if worst comes to worst you could add several dupes and blur them together? Does that help?
Posted: Tue, 23rd Mar 2010, 5:07am

Post 3 of 7

Shootout Productions

Force: 1045 | Joined: 27th Nov 2009 | Posts: 12

VisionLab User

Gold Member

Yeah, I have the same problem. I'm not sure if it will work, but you could render your base shot at, say, 45% speed, the do your particles and render that, then speed it up. Not very efficient, but I don't know of any other way. Try increasing the Tween strength?
Posted: Tue, 23rd Mar 2010, 9:12am

Post 4 of 7

Simon K Jones

Force: 27955 | Joined: 1st Jan 2002 | Posts: 11683

VisionLab User VideoWrap User PhotoKey 5 Pro User MuzzlePlug User PowerPlug User PhotoKey 3 Plug-in User FXhome Movie Maker FXpreset Maker Windows User

FXhome Team Member

VisionLab renders its particles on the frame, not between the frames, which is why this can be an issue.

Try copying the effect and offsetting its position or other attributes slightly, that might plug the gaps.
Posted: Thu, 25th Mar 2010, 10:05pm

Post 5 of 7

Helge

Force: 1600 | Joined: 16th Jan 2010 | Posts: 116

VisionLab User PhotoKey 3 User Windows User

Gold Member

Hi Guys,

thanks for yours ideas. To bad there seems to be no more comfortable solution for this problem. As increasing the particle count will unfortunately not help filling the gaps there seem to be only two solutions for this:

1.) render more frames and speed up the result (delete additional/'in between' frames
2.) use several emitters following the first ones path

If anyone knows how to do this without loosing a lot of flexibility (solution 1 needs the effect to be pre-rendered, solution 2 will mean a lot of work in case of any changes) please let me know smile

@Tarn
Do you know if there is a way to move all position key-frames of an effect at once (along the path itself)?



Again, thanks for your help! For now I'll go with these workarounds - who knows, maybe some day the developers will come up with a way to have particles created between frames.

Have a nice evening,
Helge
Posted: Fri, 26th Mar 2010, 9:12am

Post 6 of 7

Simon K Jones

Force: 27955 | Joined: 1st Jan 2002 | Posts: 11683

VisionLab User VideoWrap User PhotoKey 5 Pro User MuzzlePlug User PowerPlug User PhotoKey 3 Plug-in User FXhome Movie Maker FXpreset Maker Windows User

FXhome Team Member

Helge wrote:

@Tarn
Do you know if there is a way to move all position key-frames of an effect at once (along the path itself)?
Sorry, I don't think that's possible. unsure

Would definitely be a useful feature, though, to be able to shift selected keyframes by the same amount and adjust the path that way. Consider it noted!

Again, thanks for your help! For now I'll go with these workarounds - who knows, maybe some day the developers will come up with a way to have particles created between frames.

Have a nice evening,
Helge
Posted: Sun, 28th Mar 2010, 9:19pm

Post 7 of 7

Helge

Force: 1600 | Joined: 16th Jan 2010 | Posts: 116

VisionLab User PhotoKey 3 User Windows User

Gold Member

Thanks Tarn. It would be great if something like this would find its way into the software some day.

Have a nice evening smile