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Cascade Particle Location Question

I am trying to figure out the best ways to create different shapes using the the Cascade Particle Location modules.
I have some great looking clouds in the works and the only issue is making a good cloud shape.
I actually built these clouds in Unity before, and I was able to get a great fluffy cloud shape using the basic sphere emitter with non-uniform scaling.
Unfortunately in Unreal it seems that the Sphere location module only allows a sections of a uniform sphere.
I have tried using a few duplicate shared sphere shaped emitters in the same particle system to build the shape, but it is clunky and there are some sorting issues that arise.
What am I missing here? Is there a way to build up the locations to make more detailed shapes?
Any suggestions would be greatly appreciated.
Thanks so much
~Ben

Show us what you’ve got so far.

Alright this is the shape of the emitter I used in the original Unity build of this project and it worked perfectly for the clouds we are going for:
fae44898efc5f736add664342d1ef29b2cadcb69.jpeg

With a long squashed oval we go the coverage and shape we needed for viewing from all the angles we needed.
With the Unreal Location modules, Sphere is too…spherical. And the Cylinder is too cylindrical…I have tried add both and get some unpredictable and possibly bug-driven shapes that are closer but it is really hard to create shape variations that i need.
The clouds themselves look much much better…oy but the shape :frowning:
dc8f8f0dfd32f69672b5e444024fc456cbcb1ce5.jpeg

Do I need to do some crazy initial location blueprint magic?
Do I need to try to emit from a surface that is the shape I want? (But that will be empty in the middle…and seems overkill here)
Do I just need to open my eyes and see the control that lets me scale the sphere location module non-uniformly!

Make the initial sphere location size different to represent what you really want, Change particles to more shape variations, Make a better material that gives more shapes or a better texture. Those are the initial thoughts.

What I would do is go down to fumeFX and start creating about 64 different cloud shapes then put all of them in 1 sheet of 2k and use randomly those shapes with each other, With a few tricks i would also extract an accurate Normal map in case i ever needed it (since clouds are distant from camera this kind of lighting is usually not needed) but for making the clouds light even more epic i would make those normals and screw the extra cost. Anyway that would be my approach.

PS: After paying attention to the 2 images i can tell you that 1st one looks like a smoke cloud than a sky cloud and 2nd is getting there but some edges. You do not want to have obvious repetition in particle textures like sharp edges or any kind of tileability.

Those are all great tips…but not quite the info I am looking for at this point.
Thanks for taking the time to run through those steps.
I am not worried about the actual look of the clouds as I have all of those elements already built just as you suggested. (But in Houdini)

I just don’t have a way to make an emitter the shape I need.
The first image shows the shape of an emitter that I used in Unity that worked great as a base for the cloud shape that we need.
Again, don’t worry about the render of the the cloud…I am just wondering if is there a way to make an oval shaped emitter in Unreal?

“Make the initial sphere location size different to represent what you really want”

How do I make it not a sphere?

Give them more velocity on +/- X and Y coordinates and less on Z axis.

Edit: Hmm, clouds. I’ll take another look if this doesnt fix your problem.

use a cylinder and an initial location should get you in that shape because spheres cannot be non uniform same applies for all location primitives.

PS: We should request that as a feature really, Sometimes we need non uniform shapes on locations and initial location wont cut it.

Jacky, good thinking about the velocity, but as you mentioned later, this could give me the shape I need but not over the long term.
DieByZer0 that is the confirmation I was looking for, that you cant actually create a non-uniform primitive location emitter…which does indeed seem limiting.
Definitely a feature worth requesting.
It worked well for a great project we did with Unity to make an oval shaped emitter and emit a burst of never dying particles with a bit of initial velocity and rotation to get drifting evolving cloud.
The basic setup of the shape and movement was a piece of cake. I was hoping for the same thing here so I could just spend my time getting the look right…but now I need to work just to get the shape I need first.
Thanks a lot for the info!
~Ben

Animatedfox, Given you are working in houdini anyway, why not create a non uniform point cloud in the shape you want, in houdini, and then convert that to a polygon object, where you end up with a vertex at each particle point. Export that mesh and an fbx. it wouldnt be a very pretty mesh, but it doesnt matter, you would never see it. All you would then need to do is use that mesh with a skel mesh / surf loc location module on your emitter and emit your particles from the mesh vertices. you could get any cloud shape you ever wanted with that approach, by building the cloud shapes in houdini first.

Sandmeister.
Sorry I never responded to your suggestion. Definitely a good idea.
Thanks so much for the suggestion. The bummer is really that we still don’t have more control over the location shapes.

I wonder if you could create a transparent shape (geom) and spawn from it’s “surface / vert” from the locations tab. Have you tried that?