Peg Distribution on Object?

[Donald2B]

I seem to be struggling with something that I think should be easy. I would like make the continents of earth made up of evenly spaced pegs. I can't seem to be able to do this easily.

I have the continents already modeled from a previous project, but don't seem to be able to distribute objects across the surface properly. I may be Forest Pro a go, but thought I would throw this out here if anyone else had any ideas?

Thanks!

[beestee]

They do it with pencils with this similar utility:
http://www.ak3d.de/all/scatterfx/

The method they they show in use is distribution by map, which seems would be the easiest way to accomplish this with Forest Pro.

[Donald2B]

Thanks for the link, I had not come across that one yet.

I'm getting close to what I want with Forest, I just don't know how much I will be able to animate, if at all. I was hoping to get better results with particles, so I would have more options for animation...but this may work too.

[cheerioboy]

My first thought on keeping the pegs evenly spaced is to use particles where they attach at vertices points. So your geometry would need an evenly spaced quad mesh. And then a texture map to tell them where not to spawn.

[Donald2B]

Hmm...I may have to give that a go. I don't think I tried that since I am now using a Geosphere with evenly space verts.

[Donald2B]

Attaching particles to vertices works, but there are some issues.

The only way to mask what vertices get used, I have to use random verticies...then crank up the number of particles to a rediculous amount to cover the area needed. It would be easier if I could set the number of particles the same as the number of vertices. Then apply a mask to hide those particles that are in black areas on the map.

Any thoughts? Little rusty on particle flow setups. :/

[cheerioboy]

here's a 2012 max file, https://www.dropbox.com/s/8itujgi71v...stribution.max

I think if you place a black & white texture on the sphere, you can call out to it from the 'position object' node - tick Density By Material, greyscale.
But depending on how many pegs you have, this method seems to get bogged down.

[Donald2B]

Thanks for the file, that's pretty much what I was doing. Only I needed to offset the particles from the surface. Once you do that, there end up being 3-4 particles per vertex.

I am now going with a birth script I found while searching....gets me what what I need. I just need to apply a vol select on my geosphere and then select vertices by map to get a vertex selection. Pipe that into pflow and good to go there....now just need to get that surface offset working.

[cheerioboy]

Thanks for the file, that's pretty much what I was doing. Only I needed to offset the particles from the surface. Once you do that, there end up being 3-4 particles per vertex.

I am now going with a birth script I found while searching....gets me what what I need. I just need to apply a vol select on my geosphere and then select vertices by map to get a vertex selection. Pipe that into pflow and good to go there....now just need to get that surface offset working.

Hmm, I don't see that happening for me. Did you try from the Position Object, checking 'Separation' and also checking Delete particles if invalid?
I also selected my sphere by vertices to see how many were there, and then only birthed that amount so I didn't have exta

https://www.dropbox.com/s/3jnt79w40c...egs_offset.JPG

ah, but that sounds good using a vol select

[Donald2B]

I'm using 2014...I wonder if that is what's causing issues?

Also looking at your image, you have the two offsets the same. Make the first number negative and you will see that there are 3-4 particles per vertex, because the particle count doesn't change, so they are just stacked on top of each other.

[Donald2B]

Finally!

I did some more digging and found that using the Birth Texture set to vertices/edges worked perfectly. Gives me one particle per vertex and then I just spawn particles at -1. Geosphere still has the vol select with texture to select the vertices. The I use the speed by surface to offset the surface of the particles a little, then immediately stop them in frame 0.

[cheerioboy]

Finally!

I did some more digging and found that using the Birth Texture set to vertices/edges worked perfectly. Gives me one particle per vertex and then I just spawn particles at -1. Geosphere still has the vol select with texture to select the vertices. The I use the speed by surface to offset the surface of the particles a little, then immediately stop them in frame 0.

very cool, thanks for sharing that!