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View Full Version : Particle FX - Flat Cone?



Chrusion
11-16-2012, 07:55 PM
Is there any way of getting PFX to emit a fan blade type of particle stream... basically a flattened cone?

I know that the Cone emitter is identical to Box, thus the only way to get a conical fountain is to spew the particles out with an initial velocity on a desired axis from a very small box or sphere type emitter and then control the "cone angle" using Vibration, instead of a Cone Angle parameter one should expect to appear upon selecting the Cone emitter type. Using Vibration obviously generates a circular cone of particles. What I need is to flatten that cone way down on one axis in order to simulate a water jet nozzle that has a flat fan shape to it... think of self-serve car wash fan-tip sprayers.

jwiede
11-16-2012, 08:01 PM
Perhaps use multiple narrow-angle emitters in a row? Being better-able to "shape" the output stream from emitters would definitely be welcome, though.

XswampyX
11-17-2012, 12:07 PM
Try a 2 point poly chain bent into shape and the use the nodes to adjust the particle vectors.


http://youtu.be/Moem6IMzGjk

jeric_synergy
11-17-2012, 12:58 PM
The burning question in my mind is: how come after Swampy's videos YouTube always puts up a bunch of girly-girl DIY fashion/makeup/costume videos??? :boogiedow

Not that I'm complaining. :: popcorn::

Two-point polychains as emitters!!! :foreheads Interesting.... very innovative. How the hell do you find all these things out, Swampy?

EDIT: even without ANY nodal magic, using Swampy's emitter you get a good pattern using just the simpleminded FX controls. This is the particle dispersal pattern I got with Explosion AND Vibration set to 1.0:
109230

XswampyX
11-17-2012, 01:02 PM
The burning question in my mind is: how come after Swampy's videos YouTube always puts up a bunch of girly-girl DIY fashion/makeup/costume videos??? :boogiedow

Not that I'm complaining. :: popcorn::

Two-point polychains as emitters!!! :foreheads Interesting.... very innovative. How the hell do you find all these things out, Swampy?

Ha hah. It's your fault!

I posted the snowflakes and added the tag sparkles. Ever since then I've got all the girlie stuff!

Trial and error, or trial error, error, error.

jeric_synergy
11-17-2012, 01:09 PM
Ha hah. It's your fault!

I posted the snowflakes and added the tag sparkles. Ever since then I've got all the girlie stuff!
HA! I'll take that blame/credit: those girls are super-cute. Plus, creative!

Check out the screen grab in my edited post above: nodes not required.

XswampyX
11-17-2012, 01:19 PM
Looks good. Would make a good garden sprinkler.

Chrusion
11-18-2012, 07:05 PM
Thanks for the tricks. They may come in handy in the future, but for this project, particle sprays may not be the way to go due to the extremely high velocity needed. Thus I've settled on simple flat tapered UV mapped planes to create the look of high-velocity, high-pressure water jet sprays (using the new? cycle animated UV feature and a simple transparency image map). This will render LOTS faster and look MUCH better than HVs.

The question now becomes, how to get the spray to look like it's impacting the walls of the container it's cleaning?

My first approach works, but PFX seems highly inaccurate. This is what I'm doing.

I've clip mapped the fanned-shaped water spray planes so that they don't render on the outside of the oblong container as they swivel and circle around inside. I added an emitter parented to the rotating spray nozzle object so it shoots out a stream of high-velocity particles that hit a collision object mesh (simplified container geometry) set to erase the particles and change them from a Parent group to a Child group. The idea is to treat these parent particles as "light rays" in order to determine where the intersection of the spray object and container object is and have a child emitter explode new particle at each particle collision point to simulate the high-impact splash. These splash child particles are in the Child group so they don't collide with the erasing container collision object, but only collide with a second copy of the container collider mesh set to a 300% Bounce.

Upon hitting CALCULATE, this setup sort of works, however, as mentioned earlier, PFX appears to be highly inaccurate, even with the resolution option set to 3mm (default is 100mm). Particles from the parent emitter are not being erased during portions of the rotational arc and shoot right thru. It appears these particles, though not being erased, are being switched into the Child group and thus are immediately colliding with the Bounce collider. The result is becoming a mess. Some parent particles are colliding and thus spawning children splashes, some are not and bouncing around inside the container and hitting the other side where they are erased and thus spawn children that are no where close to the intersecting geometry.

So here's an idea... if the particle velocity is causing the non-collision/non-erasing/non-spawning effects AND because they can't be made fast enough to arrive at the geometry intersection point at the same "time" as the intersecting geometry (the flat planes are basically infinitely fast "rays"), I'm wondering if there is a way to nodally determine the point where two objects intersect and nodally emit particles from such "points?"

Chrusion
11-18-2012, 07:23 PM
Hmmm... well, scratch the above.

I found this post ( Particle Collision Event Question post 192584 ) (http://forums.newtek.com/showthread.php?25255-Particle-Collision-Event-Question&p=192584&viewfull=1#post192584) and changed the child emitter parent from the parent emitter to the first collision object and am now getting far more accurate child spawning without the adverse effects mentioned above (parent particles not erasing but changing groups and thus immediately hitting the second collision bounce object meant for only the children). And even with the parent particle velocity jacked way up!!

jeric_synergy
11-18-2012, 11:18 PM
Wow, that was some dense verbiage-- I think we need some pix.

Trying to get this straight: So, now you have TWO emitter objects (a sprayer and a container??) and the second emits the child/spawned particles? So, the 2nd emitter (the container) is emitting particles by Collision, right?

(Sounds fun!)

Chrusion
11-19-2012, 11:49 AM
Yeah, I can pack 'em in there. :p

Try the pix below on for size.

The parent emitters are the "light rays" shooting out to intersect with the container. The child emitters take the Recorded Center Point of each parent particle collision and spawn 20 particles/frame.

Since there are two spray jets per rotating assembly, each parent needs it's own collider mesh and subsequent child emitter.

Now all I have to do is multiply this 2 more times for the other 2 rotating nozzle assemblies. That's 6 clones of the collider mesh, 7 including the child bounce.

If I recall, single point polys don't render with motion blur trails like they use to in LW prior to 8 or 9, right? That this was due to the change in camera types... classic vs. perspective? But to do so requires enabling the multipass motion blur in the advanced cameras? At any rate, render times are expected to be very long due to the number of MB passes to get those once smooth long trailing lines. Or, just switch to classic, but what would the rendering drawbacks be?

jeric_synergy
11-19-2012, 01:35 PM
I have project-envy. ;)

Dean, so what settings are used on the secondary/child emitters' particle controls? Is it "birth by collision"? (trying to ask this 'by memory'...)

Probably a screen grab would explain it fastest.

Chrusion
11-19-2012, 02:20 PM
Child emitters (parented to collision mesh with Record CP checked on) have nozzle type Parent-Collision and emit 20 particles/frm at 3m/sec Vibration.