Deep Space WIPs

[parkdalegardener]

Well maybe the deep space between my ears that keeps them from banging together. At any rate I posted a nebulae frame from an anim I was working on in the gallery a month or so back. That started a conversation in the Coffee Shop. Now I can't post anim WIPs to the gallery as off site links wont work from there. Fafnir's ladies are keeping an eye on me after I ran out of paper and crayons over at my little table in the Coffee Shop. They are afraid I'm gonna start carving rotational vector math equations into the table top with my trowel. That and I'm encouraging others to draw on the walls there along with me. My WIPs are littering the gallery floors and The Nurse is gonna think I'm off my meds wandering the hallways looking for a corner to hide in and play with myself. (No not like that.) At any rate the lovely Aelin pointed me over here to a vacant room where I can hide out and play.


Now; I'm going to work on a side project in here. Not my normal gig. I am using Blender, but as per our discussion in the Coffee Shop; it's concepts and results, not software, computer power, or render engine that we are looking at. We want to build a Deep Space environment. That is the aim. This is not going to be a Blender tutorial showing you click by click how to do make your own. I am just a guy not a guru. I don't care if you draw on the walls in here to show what and how you are doing but NO FULL SIZE IMAGES. If you have something that really deserves to be seen, it probably won't get noticed here. Post it in the Gallery. I'm not about sucking bandwith and bypassing the posting limits here on the Forum. Participation is welcome however. No judgments.

[parkdalegardener]

Ok. Here is a size and if it's too large TL can let me know. I'm not going over what's happened up till now in detail but, the last thing I did was set up an asteroid field to begin the make up a planetary ring system. I made up a bunch of meteoroids from spheres with a displaced noise texture on them and then hit them with another noise on top to make craters. The meteors were scattered as particles throughout the volume of a torus primitive and given random rotations and scales so as to provide variety.  Then the torus containing the particles was set in motion to provide an overall volume and rotation to the particles. We've seen that result.


Looked pretty good. But. There is a problem. We need more details. Rings have collisions between particles. That's where the rotational vector math calculations come from. I don't have a supercomputer and the deep space between my ears can only handle so much 3d vector visualization without running simulations.


It's screaming hot here today and I can only exchange so much heat here before I fry something. The box doing the sims is clocked hot and liquid cooled but climate change doesn't care. That means I went at it a bit differently. The meteors in the following image are the same rocks as yesterday but I reconsidered calculating them in a volume. This is hair on a plane I cut into a flat disk with no center. Have to put the planet somewhere. A noise with a huge amount of distortion was placed on the plane and the hair generated on the vertices instead of the polygon faces.


This should make the math easier doing close up collisions between particles. After all. The meteors have to break apart upon impact in the beauty shots that will happen as our ship (nope haven't made one yet) moves through the rings.


The planet in the centre is only a place holder despite it's rotation. After all, the surface isn't boiling in this image and there are no solar flares. It's just a light.

[Wizzard]

Heres hoping for an arctic cold snap.  For heat removal of course. 8 )
I like the look of scale you got. the movement of individual rocks is quite impressive, keeping in mind heat limitations.  Sounds like building a comp inside a freezer wasnt that bad an idea, 8 )   thanx for the look in.   Cheers

[parkdalegardener]

I think that the change from volumetric placement of the particles to planar with distortion is the way to go with this. Parallel to this playing around there is a background project I decided upon last night. I am going to turn this into a generator via geometry nodes. In other words a stack modifier that will allow me to add everything procedurally. For this "ringed planet" part of the project I built the geonodes that can display the number and size of rings I wish and populate them with particles (meteors). I haven't got past that yet. I will.


So next up will be the beauty shot collisions. Meteors bang into each other, break apart and the fragments move off in directions determined by the application of the original force parameters. This brings up a need to speak of instances.


The particles are not real geometry. This is important. It means that they are much less taxing upon your hardware than actualized geometry. The simple plane test above has ONE uv sphere that textured with displaced noise to provide shape and a simple voronoi used to add the craters. Slight scaling on the x, y, or z to a couple of duplicates and that group of meteors are used to create thousands of particles. Thousands of particles that are really just the one original. This is good. The bad is that there are thousands of particles that are really just the one original. If I change one, they all change.


Poser people. You have something similar. If you duplicate something in Poser you just reference the original geometry and whatever is associated with it. If I load an object in Poser and repeatedly load that object from Import or Library I can rapidly fill up my available RAM. Load the object and repeatedly duplicate it via menu command and the original you loaded is referenced repeatedly. My RAM load stays low. Unlike Blender though, you can modify duplicates without modification of the original geometry.


That means that in Poser you can also generate a crapload of duplicates upon a plane which you distort with a noise. The same way I did with Blender. Issue in Poser that there is no way to automate the process without using something like Ken1171's Scatter Tool which he sells in two versions, one for P11 and one for P12. They are not interchangable though the results are. I am not pumping his products. I don't know the man and I don't use his tools, but; he has exploited this feature and made it easier for Poser people to take advantage of.

[parkdalegardener]

This brings us to today's problem. I'm working with unrealized instances for my meteors. How do we have collisions between things that are not there? Stay tuned.

[parkdalegardener]

Heres hoping for an arctic cold snap.  For heat removal of course. 8 )
I like the look of scale you got. the movement of individual rocks is quite impressive, keeping in mind heat limitations.  Sounds like building a comp inside a freezer wasnt that bad an idea, 8 )   thanx for the look in.   Cheers

I'm waiting for TL's rain. Supposed to come today. The version of that done inside a volume is really what I want, but the math for collisions is tedious so I dropped it to the 2d surface you saw for the math. If I add the displacement of the noise on the 2d plane to the position of the particle on that plane I can calculate the position of that particle in 3d space. I need that to be able to call for a collision. Remember, all this is virtual. No realized geometry. That is why it is so important to be able to know where and two particles are at any given time. Remember; what I do to one, I do to all. This means I will need to make specific particles real before they can collide and break apart.

[thelufias]

Hope you just get the rain PDG and not the rest of it.  Good job setting up the thread...

[Wizzard]

In theory, instancing duplicates the object with parametres, weight, collision etc.
At least in "high end" proggies like XSI or Maya, they do that. Then again, both do "realistic" hair simulations  after churning away for some time.

Like the differance twixt a 2CV and a Veyron in power. 8 )
Cheers

[McGrandpa]

Interesting exercises in real physics, PDG.   I like  the anim of the ring field particle motion.   So, in that one, each particle is a real instance, not duped ?  Then will come the orbital path later.   Sounds like fun.   

[parkdalegardener]

There are no real instances in any of the posted images or animations. They are all  random scale and rotation manipulations of the original uv sphere mesh currently sitting inside the "sun."


The sphere to be instanced inside the "sun" has been given two textures. The first is a displacement/bump to give shape and the second is a surface noise to give the craters. 



The best results I come up with are if I place the particles inside a volume. The torus for instance gives me a volume shape that is perfect for orbiting rocks. Random placement inside the torus and then rotating the torus results in a "ring" which in turn gives a 3d environment of rocks in motion around a central point. The "sun". All the particles are in their own random rotations separate from each other and the rotation of the torus.


All that works fine. Perfectly. So I scrapped it and started over. Yeppers. Trashed it. The  solution imaged above is a different setup. I want to dump all this together into a single generator for ease of reuse and environmental continuity across shots.


Generators are exactly like they sound. They are stacks of instructions to execute on an item and give a predictable result. Unlike morphs they can create, alter, or destroy geometry.


That leads to where I am now. Eye glazing time:


Using geometry nodes I started with a vertex.


The vertex is moved a distance from world origin.


That vertex was given a distance to travel resulting in a line of fixed length.


That line was extruded on a curve resulting in a 2D disk with an empty centre where the planet, sun, or what have you will go.


The disk is then subdivided.


A small uv sphere was generated at world centre. The particle instance. I leave it there so I know a reliable x,y,z co-ordinate system for the rotations.


Next up generate a particle system on the disk and use our sphere as the instance and the disk vertices as the placement points. One could probably use the faces.


With a known fixed origin (0,0,0) for each instance I can set up random rotations.


A noise texture is placed upon the disk. The resulting distortion moves the vertices of the disk around in 3D space and the instances with them.


Rotate the disk around it's origin and the instances all rotate with it while rotating on their own axis. Wheels within wheels.


The noise texture gives me a reliable positional map of the particles. After all; each particle believes it lives at 0,0,0. I need to keep the math reasonable. Volumetric  placement of the particles made that a nightmare when I started to figure out intersections.