lighting a point cloud

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Hello,

Can someone explain how adding normals to point clouds alters the way a point cloud will render? Is there any discussion threads of this anyone knows of?

Thanks!

Pip.
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depends how you render points but N might be used for shading
Albert
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So, this is for a project, I have a particle simulation of spray off a wave, and my lecturer says I need to have normals on the particles/the point cloud to pass it to my partner who is lighting it. At the moment I can't get hold of either of them, so is it as simple as adding N with a facet sop and that's it?

I'm not sure about the concept?
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not really. Facet would calculate normals based on geometry but in your case, You do not have any geometry so facet won't work.

Normals would help shade particles as “volume shape” so direction is quite important. You could get some sdf volume (maybe create one from those particles if you don't have any), calculate gradient from that sdf and pass it onto your particles.
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What about pointSop and add normal. Delete the channel and add a number to get the normals facing the direction you want. There are also numerous ways to manipulate normals via vops, pointWrangle, etc.

Also search around…I think Jeff Wagner has an example of a good krakatoa like point shader. I will post one when I get st my computer.
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sl0throp
What about pointSop and add normal. Delete the channel and add a number to get the normals facing the direction you want. There are also numerous ways to manipulate normals via vops, pointWrangle, etc.

Also search around…I think Jeff Wagner has an example of a good krakatoa like point shader. I will post one when I get st my computer.


no matter if you use point sop or add attrubute or vopsop, if your normals will point one direction, your lighting will also treat it as flat surface (pointing in direction of your normals)
So to get good looking shading of your pointcloud, you should create normals that represent general shape.
Albert
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pip31
So, this is for a project, I have a particle simulation of spray off a wave, and my lecturer says I need to have normals on the particles/the point cloud to pass it to my partner who is lighting it. At the moment I can't get hold of either of them, so is it as simple as adding N with a facet sop and that's it?

I'm not sure about the concept?


HI! pip31.
It may help. I saw form "https://vimeo.com/47004433 [vimeo.com]“ by Igor Zanic.
A master of fluid.
”Also try to add specualar to splash, you will get much better resault, you realy need that, this is what peoples don't use when they render splash or foam particles.
For specular on splash you need normals, for example you can mesh splash particles and transfer normals from mesh to particles, and then render particles with PBR with surface model, there is option on geo level use point normal for render. You can also tweka normal with your shader like read part normal add noise on it, so you can break spec little more"


For now i also lack a nice way to render the foam or spary.
If you get any skills, help me please!
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