partigon size

[Hiraghm]

Is it possible to set up a partigon emitter to increase or decrease the size of particles emitted over time?
I set up an envelope on the hypervoxel size, and they just all got bigger at a given keyframe. What I want is for it to look as though the emitter is emitting bigger and bigger particles (so the older particles will be smaller...)

Any advice?

[Hiraghm]

I can't believe no one has wanted an emitter to change the size of particles emitted over time.

Newtek? You guys have any clues about this?

Should I stick in it feature requests?

[stib]

..well nearly, what I wanted was for the particles to get bigger as they age, for an expanding cloud of gas in a fire safety video. So the ones that have just been emitted are little while the ones that are old fullas are big. to match the texture that I have on them which expands according to their age. But putting an envelope on the particles size changes em all together.

What we really need is to be able to put a texture on the particle size control, and use gradients with particle age as input.

(BTW. If you're applying a Hypervoxels texture to those particles you can use particle age as an input for the hypervoxel particle size. Of course this doesn't do anything for the particle dynamics. You prolly already knew this, but.)

[richpr]

Can you change the scale of the texture? Then you could make the particles equally sized, but the texture details grows... giving the appearance of the particle getting bigger... like if you would have a circular blob in the center that grows... around the blob it would be transparent...?

I guess you would need multiple textures/envelopes for variation..

[stib]

that's what I've done, but the particles are interacting - bouncing off each other, and other objects. The size of the particle (the PFX particle not the HV particle), determines the way it interacts. So a 2m wide particle will bounce off anything that comes within 2m of its centre. Making the particles grow at the same rate as their texture simulates an expanding rushing cloud of hot gas very nicely. Or it would, if I could.

in your example a group of expanding blobs would just grow into each other, instead of jostling each other out of the way.

I've got an envelope on the size of the particles, which is a kludge, because all of the particles get bigger, even the newbie ones coming out of the emitter - which makes them bounce sideways off each other instead of going straight up, buuuut you don't notice it that much and this is an educational vid I'm working on after all, not terminator 4.

Still it would be nice to be able to do. just for the sake of realism when using particle systems to simulate real world events.

Oh yeah has anyone else noticed that once you save a particle system's movement, any changes you make later won't stick until you save it again? So if I open the scene, do some tweakage, and render the frame the particles lose all the tweaks for the render. In fact they lose all their interactions save gravity and initial velocity. So you have to tweak, save motion as.., and then render. Very confusing for noobs..

[toby]

You can add a 'particle age' gradient to the particle size channel (in the HV panel)

[stib]

:mad: sorry, but you're confusing HV particles with PFX particles.

My scene has HV textures on PFX particles. The size of the HV particle determines how big the particle looks, but it has no effect on the particle dynamics.

So HV textures that grow, grow into each other and join up, when I want them to spread out as they go, following the guides I've created out of PFX collider objects. Simply increasing the HV particle size just makes them grow right through the walls.

[toby]

oops - I didn't see your last post - sorry

[Hiraghm]

Here's what I ended up doing.

Not exactly what I wanted but it wasn't a serious project anyway.

C-One Logo (http://www.xtimports.com/animation/C1Earth_03.mov)