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pekka varis
02-02-2018, 01:06 AM
I have a small problem with particles.

See this image please:

139874

I need to have more particles at the center of the ball shaped emitter. I am looking for a particle trail shaped like the red painting I have made in my image. Can anyone help? I am also looking for to use group emitters, I wrote a different topic about this - just want you to know:

http://forums.newtek.com/showthread.php?155933-Group-particle-emitters

Pekka

prometheus
02-02-2018, 06:53 AM
I have a small problem with particles.

See this image please:

139874

I need to have more particles at the center of the ball shaped emitter. I am looking for a particle trail shaped like the red painting I have made in my image. Can anyone help? I am also looking for to use group emitters, I wrote a different topic about this - just want you to know:

http://forums.newtek.com/showthread.php?155933-Group-particle-emitters

Pekka

Several ways..
Simplest...Use two emitters.
You can also try with collision forces.
You can also use a sphere or point cluster with more points in the specific area at initial birth rate...
Lastly to complicate it...Use a procedural texture in birthrate..but that is tricky.

pekka varis
02-02-2018, 07:03 AM
Thanks! Two emitters - that was what I was thinking too. But before that, can you please tell just a bit more how to do a point cluster on this scene with balls flying around? See the image in my first post on this topic above..

I cannot use balls with more points on center area, since these balls are rotating and spinning all the time.. Thatīs why this point cluster sounds more interresting. But I cannot find any information about "point cluster" on documentation. Under Fiber FX yes but on normal particle emitter.. Please can you just tell me a bit more, prometheus ?

prometheus
02-02-2018, 08:45 AM
Thanks! Two emitters - that was what I was thinking too. But before that, can you please tell just a bit more how to do a point cluster on this scene with balls flying around? See the image in my first post on this topic above..

I cannot use balls with more points on center area, since these balls are rotating and spinning all the time.. Thatīs why this point cluster sounds more interresting. But I cannot find any information about "point cluster" on documentation. Under Fiber FX yes but on normal particle emitter.. Please can you just tell me a bit more, prometheus ?

Not sure if youré gonna have balls spinning and rotating, that takes a bit of a trickery to set up to avoid the main ball rotation and spin affecting the emitter.
But for point cluster, you can simply take one ball, copy it to another layer, subdivide that copied ball a bit more than the origian ball, then select the area where you want the emission, and copy those points, hit"k" to delete polygons, and paste only points back, in layout or modeler..you need to parent this point cluster layer to the main ball, hit p for properties for the point cluster layer and add fx emitter, set itīs nozzle to vertices.

MonroePoteet
02-02-2018, 09:03 AM
I may be missing the point, but it looks like what you're after is a fading trail behind each of the balls, maybe something like this:

139876 139877

139879

If that's the case, you can use fading HyperVoxels to do the trick rather than trying to adjust the particle emitter. Sample scene attached.

In the sample scene, there's just a Null as the emitter, and the rotating / spinning Ball is parented to it. This allows the Ball to spin in any way without effecting the emitter, while the EmitterNull can move in any way dragging the Ball along with it. In the sample scene, I just used a Noisy Channel modifier on the Heading and Pitch for the Ball (Noisy Channel is in the Modifiers tab of the Graph Editor).

For the surface of the Ball, I used the Cells procedural on Transparency and Luminosity.

For the EmitterNull, it's just sized down (in my case to .1,.1,.1) to center the emitted particles close to the center of the Ball. Then, HVs are applied with Gradients (in the Texture panel) based upon Particle Age to change their Size, Color, Luminosity, Opacity and Density over time, making the trail fade away. The "shape" of the Gradients can be changed to make the trail fade away faster, slower, or in a particular shape.

Here's the Gradient setup for the HV size, with similar Gradients on the other HV parameters:

139880

Sorry if I missed the point!

mTp

prometheus
02-02-2018, 11:15 AM
I may be missing the point, but it looks like what you're after is a fading trail behind each of the balls, maybe something like this:

139876 139877

139879

If that's the case, you can use fading HyperVoxels to do the trick rather than trying to adjust the particle emitter. Sample scene attached.

In the sample scene, there's just a Null as the emitter, and the rotating / spinning Ball is parented to it. This allows the Ball to spin in any way without effecting the emitter, while the EmitterNull can move in any way dragging the Ball along with it. In the sample scene, I just used a Noisy Channel modifier on the Heading and Pitch for the Ball (Noisy Channel is in the Modifiers tab of the Graph Editor).

For the surface of the Ball, I used the Cells procedural on Transparency and Luminosity.

For the EmitterNull, it's just sized down (in my case to .1,.1,.1) to center the emitted particles close to the center of the Ball. Then, HVs are applied with Gradients (in the Texture panel) based upon Particle Age to change their Size, Color, Luminosity, Opacity and Density over time, making the trail fade away. The "shape" of the Gradients can be changed to make the trail fade away faster, slower, or in a particular shape.

Here's the Gradient setup for the HV size, with similar Gradients on the other HV parameters:

139880

Sorry if I missed the point!

mTp

I donīt think that is what he wants, he wanted thicker density for inner particles, yet having lower density around that, and if you would to do that with one emitter only and hv shading only, you would need the outer part of the trail be thin in density, while having inner most trail as thicker density, that may be doable as well though, with for example a local denisty gradient in the dissolve channel.
Your example is only fadint the size away at particle end...showcasing a sort of tapered end, but not a combination of inner thickness and outer thinner density.

MonroePoteet
02-02-2018, 02:25 PM
I donīt think that is what he wants, he wanted thicker density for inner particles, yet having lower density around that...

OK. In that case, I'd just clone the Emitter from my sample scene, reduce the size of one of the emitters to create the center dense trail, and then modify the Gradients on the HVs for the other emitter to have the maximum Luminosity, Density and Opacity at something like 20% or 30%. Sample scene attached with various modifications.

139882

mTp

4dartist
02-02-2018, 02:48 PM
I thought I'd give this a shot. I just copied a sphere a bunch of times making it smaller and smaller, then used it as an emitter. It basically makes the trail have more density at the center. It seems to work good.

prometheus
02-02-2018, 03:08 PM
I thought I'd give this a shot. I just copied a sphere a bunch of times making it smaller and smaller, then used it as an emitter. It basically makes the trail have more density at the center. It seems to work good.

Yes..that works well too, typicly density is compressed, as you scale down any object emitter.

4dartist
02-02-2018, 04:03 PM
Yes..that works well too, typicly density is compressed, as you scale down any object emitter.

Oh, well I didn't scale the emitter, I made a dozen spheres on the same object layer that are smaller and smaller, then used that one object as an emitter. I wasn't sure if you thought I cloned the emitter and scaled them down, which would work but the hassle of many emitters and such would be bothersome.

pekka varis
02-03-2018, 01:33 AM
SO good tips! thanks people.

I shall try copying the ball to same layer by itself ( so clean and fast solution !) and I also try this hypervoxel tech. Together they shall make the scene so much better!!

pekka varis
02-05-2018, 12:11 AM
Thank you! I made it using the multiple spheres inside each other:

http://www.catchline.fi/toveri/loikka-temp5_000.mp4

Since I am going to use many more balls and Moton blur and DOF - I decided the fading HyperVoxels tech was too much for me this time since I cannot control the emitter or hypervoxel settings through groups and must use copy paste for each ball. Now I managed to have only one particle emitter per ball and thatīs cool for me now. Great support again from this forum!

pekka varis
02-06-2018, 01:00 AM
I used the hyperfoxel soluotio that 4dartist made after all :)
But since motion blur & DOF I left the particles sharp.

This topic continues here:
http://forums.newtek.com/showthread.php?155978-Small-overall-motion-to-particles&p=1536271#post1536271