Requesting suggestions on how to model energy and flows

Support Animation and Rigging
#1

I’m new to blender however I’ve done a number of animations with just ray traced frames. I’ve just finished an animation for a professor friend as an intro to the concepts in one of his classes. At one point he wanted a model of static electricity moving along the surface of sphere. I wrote a python program to generate a couple million tiny spheres which were then plotted along the curve of the sphere. This looked ok but I’m not happy with it (it looks like what it is). I’ve played with particles in blender however all I can seem to create is a smoke effect which tends to react to wind and gravity (static charge does not behave that way). Can anyone suggest another approach that could be taken?

A perhaps related question is my friend has asked for an animation of a hubble telescope image of a black hole (including the movement of the gases int o it). If I could get particles to strictly move around an object, and not interact with wind and gravity, I think I could do this with blender.

Any recommendations/suggestions/pointers appreaciated.

Thanks,
WIlliam.

#2

Check what Ammusionist did here:

https://blenderartists.org/forum/viewtopic.php?t=56972

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#3

Thanks for the suggestion Fligh%. I had searched and looked at that post, even downloaded and played with it. It doesn’t quite achieve the effect we’re looking for, or perhaps I’m dense (btw, I’m a programmer, not an artist, my materials tend to all look like variations on pastel colors).

Anyway perhaps a more detailed explanation will trigger some other ideas. When charged particles leave an emitter they tend to flow out uniformly over the surface of a neutral or slightly oppositely charged object, like glass. The uniformity is due to them repelling similarly charged objects and attracting to main object. Now introduce a collector and the particles will flow over and be absorbed by the collector, a strongly oppositly charged object. Add in a rotational swirl effect and that’s what I’ve been asked to produce. It seems to me that the forces and deflection capabilities of particles (perhaps even the curve guides) would solve this. I found the animation of particles on the blender 2.40 announcement to be intriguing however I’ve not been able to get a similiar result in my own trials. Does anyone know if/where the .blend file for that animation exists? Or better a tutorial on how that was done? (There seems to be alot of interest in hair modeling and I’ve done those tutorials to expand my skills).

Humm…I recall another post about animating a particle emitter, I’ll have to go find it.

Anyway thanks again, I see that you frequently help and are reference in this forum. I’m used to mailing lists which tend to download the archives of and scour for solutions. Does phpBB have a similar capability? I’ve tried the search function however it returns “can’t connect to database”.

#4

wkv,

as a programmer it might just be easier for you to dig into the particle emitter source and add a new field type.

LetterRip

#5

Well I guess I was concerned that I end up creating what I have now :smiley:
Before charging in and hacking it would be nice to understand a little bit about what the capabilities of the existing system are and since my experiments have not been able to reproduce the example animation it’s clear that I’m missing something. Also the mathamatical concepts involved are just dim memories, I haven’t seen or thought about algabra or geometry in 30 years. Even my good friend with a PHD in advanced calculus couldn’t recall how to evenly distribute points on a sphere, pretty embarassing; however, as they say, if you don’t use it you lose it.

On a side note there appears to be a degeneration in the random value selection when there are more than one emitter in a scene. I’ve been following the “Creating Star fields and Nebula” tutorial on the cogfilms site and whereas the Nebula turns out fine, both the Star and Glow emitter planes are plotting mostly lines. I’ve tried changing the seed values with very little effect. Is there something I’ve missed?

#6

You might contact jahka,

Janne Karhu <janne DO karhu AT palvelut DOT net>

He did the particle update

are you talking about texture controlled particle emissivity?

LetterRip