Spiral Galaxy



I really liked the last 20 secs as the galaxy merged together. Whats with the random glass man standing on a ball?

@Steve: Thanks. Yeah, the last twenty seconds are actually the first twenty seconds before the smoke sim lights off. I just threw it in there because I liked the physics of it.
“the random glass man standing on a ball” is my channel logo. Actually, it was one of my first mocap experiments.

Well, it was one of my first mocap experiments that didn’t end up with Taffey People or someone stuck in a wall as if they had been part of the Philadelphia experiment…

I had forgotten about the Philadelphia Experiment conspiracy theory! =D MoCap is very difficult. You did pretty well. =) And galaxies are, of course, cool as well, though the stars were a bit big, I think, but that’s the only critique I can think of.

Great work!


Woohoo! Always a great feeling when one of your Heroes Of Sci-Fi Art even watches something you’ve done, even way cooler when he critiques it!
THANKS DAN! Glad you liked.
Yeah, the stars are slightly big relatively speaking. There was a point in this thing when I realized that, no matter what, there probably wasn’t anything I could do to ever make a project like this approach “realism.” After weeks of working on it, I just threw my hands up and said “This is going to look like the cutscene intro from Spore, and there’s nothing I can do about that!”
Anyway, thanks for watching. :slight_smile:

Is that halo surface meshes or particles or smoke or ?

Yes. Exactly.

Alright, well to answer your question without running the risk of being called a horse’s ass…
You’re right. It was all of the above.
I made a Group of little stars with different Emission Strengths and colors. They were all different sizes. On another layer.
Then on the first layer I made one cube to emit them as a group, Pick Random. I didn’t emit a whole bunch of them. Maybe 20000 or something. There was a Vortex force in the center of the cube, along with a Force force, set to a negative number. This was the Black Hole at center of the galaxy. The Vortex force provides the spin of the galaxy.
I spent many whole days playing with the strengths of the Vortex and negative Force, trying to get a happy balance that wouldn’t let the particle stars fly off into space or devour them down the maw of the Hole. I also tinkered A LOT with the mass of the star particles, their size, and each of them had their own attractive force to sim the gravity of stars. This played merry hob with my old processor. Along the way I bought a new computer, called The Beast. It is my now my lovely wife.
Then came the Smoke Sim. Yes, you can imagine.
Without going into painful memory, I’ll suffice to say that these particles affected the flow of the smoke, but not quite to my heart’s content.
Then there was a second mesh, a sphere, a little bit larger than the original cube, emitting even more stars. These stars had nothing to do with the smoke sim, and were just there to provide more stars. I think that was an additonal 30000 stars or something.
Unfortunately, they affect the smoke sim, and there wasn’t much I could figure to stop it.
And, on the outside of those meshes, was the domain of the smoke sim. This is the kicker, and you have to make sure you don’t scale your domain up too much, as it will kill you when you put the damage on. This is why I spent so much time trying to get my stars to orbit decently, without going space psycho. Nothing is uglier than seeing smoke flowing against an invisible wall.
Anyway, that’s it in a nutshell.
I more or less considered the whole thing a fail. My cat was shot by an idiotic neighbor boy, so the only recourse I had was to throw myself into this project and try not to think of the past five years I had my cat, my best (usually only) friend for all that time, and all our adventures.
I moved to a spectacular new house to get away from the sound of random gunfire.
This animation sat on my desktop for a few weeks, and finally, the other day, I edited the vid, and posted it.
I hope this helps you some if you’re thinking of doing a similar sim. Along the way I discovered that it is possible, at least in miniature and roughly, to do the same multiple galaxy collisions that NASA has posting lately, and that was my initial goal for the project. Maybe later… (I have several new things I’m working on at the same time now, and none have anything to do with space physics, but mostly gun physics (and politics))
If you’re planning such a project such as this one, all I can really say more is GOOD LUCK. A convincing galaxy sim vid is not for the faint of heart (nor the faint of processor…)
And, of course, thanks for watching and commenting.
Merry Christmas, Happy Age Of Aquarius :smiley:

Yay! I love physics, they need to add X forces for fields on particles, rather then 2 :frowning: I can’t do gravity, magnitisim and electric fields at once…

Beautiful! Really nice work. And yes, I’ve had my share of problems trying to get the Vortex Force to act like a friggen’ VORTEX and not fling the particles off into space! :wink:

They need to add another set of forces
(Track - rotates particles to face a target)
(Local Particle oriented Forces)<x,y,z>

This way I could emit a particle, have it track, and then fly into a target, or any number of cool things… I wish I knew more about python…

https://www.youtube.com/watch?v=Imy9Aby86k8 is my take on it :slight_smile: gravity is space time curvature, in this case it is a bowl…

Thank you. That’s kind. Yeah, sounds like exactly what consumed a few of my days while on this project. Well, as I said, that’s the reason for the Force force set to a negative strength. It attracted the particles, but it was tough finding a balance. I ended up using figures like -pi for the Force, and phi for the vortex, etc. Then I just started throwing random figures into it, playing with the mass of the particles… etc.
Lots of fun for a lost week. :smiley:

BluePrint, I like that vid. Looks like the beginning of my experiments with making a spiral galaxy.
A couple of tips: turn off gravity. Your particles are falling into a bowl. That’s what’s stopping them from moving freely. So, get rid of gravity, get rid of the bowl, make their emitter invisible, and let them spin in space. (Unless you’re actually trying to make particles falling into a bowl. In that case, GREAT JOB!!! :D)
As for getting particles to track to a target, that’s why you put in a Force, set to Point force, and give it a negative strength. This will attract the particles.
As for getting the particles to always point at the camera, you can actually do that if you set the particles to be emitted as Billboards. There is a setting in Billboards that will make them point at the camera regardless of whatever they do. I haven’t played with that in years (it was actually my first particles experiment, several years ago when I first started playing with Blender) so it’s probably been improved a lot. It’s used heavily in video games. Instead of using particles (as I was stupid enough to do in this vid…) they use Billboards, called “Sprites,” have them always face the camera, and have them show an image on their face, Shadeless, of an explosion, or a laserbolt, or whatever. This is actually an incredibly useful tools for animators, as little Billboard Sprites with little images on them take VERY little memory to render, thus greatly speeding up the render time of an animation. It’s something I’ve decided to start doing a lot more of in the future (but, up till now, I was just too awesome to settle for CHEAP animation tricks. So, I paid for it by trying to get the “real thing,” spend a week on a render, and hate completely when I finally watched the animation for the first time… There is a LOT to be said for Fake Trickery. Not the least of which is that animators who know these kinds of tricks can actually render great-looking animation quickly and enjoy watching the result when they are finished…)

I’m still learning. I’m learning that I hate the way I’ve made animation up till now. I always learn that when I watch the old guys who have been doing it for a long time and know their shit. But, you learn stuff from watching them. So, hopefully I won’t suck so bad soon. I can dream, right?

Like this guy here, TomWalks. THIS guy is a friggin genius. I learn so much just watching one of his videos that I always feel I need to completely scrap everything about the way I’ve ever made animation and just do it the way he does. But he has a very unique approach. Watch all his videos, and tell me you don’t come away from the experience with your head on fire.
For this galaxy project of mine, I did by experiment and trial and error. Then, just after I posted my vid (after weeks of FAIL,) I found this vid of his. I wanted to slap myself.
If you want to make a galaxy, or learn clever things about particles (or anything in Blender) TomWalks is the guy to study!..

I have the “bowl” there to represent gravity, the downward pull of real gravity causes the particles to be pushed together by the bowl :slight_smile:
So I have Force repel on the particles, and I have Vortex on the particles, and the “gravity” is from the mesh collisions, but it demonstrates valency nicely. :slight_smile:

any particles with to much energy, hop up to the next valence.

Huh. Well that’s a pretty neat way to do conceptual physics. Sort of the old “Einstein Trampoline” in 3D animation. Very cool! :smiley:

I’ve also been playing with galaxy of late; only enough to try an get the idea… it seems that to get them really good, you have to spend a lot of time experimenting and the render times (if not using those billboards at least, thanks) can be heavy even on good hardware. Good thread this. Not perfect exults yet but a very good study. Agree TomWalks has some amazing methods / results.

Yes, you’re right, it is a very difficult project.
And keep in mind, this is just ONE galaxy.
For me, the point was not, in the first place, just to make a galaxy. Instead, this little galaxy was just a warm-up. My goal was to see if I could recreate something like the recent sims that NASA has done (with a warehouse full of banks of the newest fast computers) of several galaxies attracting one another and smashing together to form a much, much larger very complex large spiral galaxy like the Milkey Way or Andromeda.
I realized that this could be possible. I found a script to simulate the effect of meshes that have gravity and attract other meshes. I tried it out and it works really well.
The problem was that, while I wanted each little mesh in that script that I found to represent the black hole core of a galaxy, I first needed to practice and learn how the black hole core of a galaxy interacts with the particles that represent the stars of that galaxy. And what about dust and smoke, an integral and obvious part of any decent galaxy?
So, evetually I may go back to the larger project. I may have four or five galaxies like this one, falling around each other, sucking up the stars and gas from each other, colliding to form a colossal giant spiral galaxy like our future AndromedaWay Galaxy.
But first I’ll need to buy a couple of more i7s…

I think that blender could model all of this effectively, the big thing would be to have all of the real forces that are at play make the system, So we have Electric, magnetic, gravity, momentum, and Electro-Magnetic-Waves, and all of these can be stewed down into-neutrons,protons,electrons and photons, and energy exchanges like conduction, convection, radiation, wave propagation and electrons absorbing photons and re-emitting them, in short Particle-Blender.
I can easily balance forces, what we need is to replicate them.

I can model a surface as faces etc, but this will never be physically accurate, defining a volume and the probability ratio of this element to that element define boids that are the bits and pieces of things, it can represent anything,

Currently we may only be able to simulate a single cell this way accurately, and not in real time due to the parallelism of nature, but this is rapidly changing, and object based processing is on its way, just think of a piece of hardware that was tiny, that it’s whole job was to represent a neutron or photon etc, not unlike a transistor, but highly specialized, now build a vast network of these, with a laser based micro solar input/bus ( I know it sounds odd) so it can be infinitely parallel and powered by the laser inputting its data, and it’s data/output emissions were its waste heat turned into light?(LinkToArticle) this grid of specialized processors organized by a traditional cpu and gpu could handle just about any simulation you could throw at it, and could change the very fabric of invention.


Wow, thanks for sharing the TomWalks’ tutorial. It’s even a really cool example of a tutorial let alone the subject :wink: