3ds Max: Evenly Distributed Polar Array

[Sassmouth]

Hi, all.

 

I am trying to create something similar to the attached image. I thought it could be done simply using the array tool to make a polar array. I tried several combinations, but the circular patterns of the array were always visible in the final result; I could never get an even distribution of elements across the sphere (they always bunch up near the ends, with the space between them shrinking as the elements approach the array's origin).

 

After looking closely at the attached image, I was able to see the pattern--the green "trees" are each surrounded by 6 yellow rods, which form a hexagon. What I'd like to know is how I can take that simple module, 1 element surrounded by 6, and evenly distribute it in an array across the surface of the sphere. AutoDesk's help pointed me toward Particle Array, but I couldn't seem to make order out of its chaos.

 

I'd appreciate any insight.

 

Thanks,

Steve

[Bruce Hart]

Here's one way:

create a geosphere in Icosa mode with say 3 segments. Use "compound objects scatter" to scatter the first object along all vertex points. Extract the operand sphere and use polygon inset (by polygon) to create faces in between the newly created scatter objects and detach them (see polys in red in image). Get your second array object and scatter them on these new detached faces, this time by face centers. This should give you the array you are looking for.

 

Edit: as pointed out below you could just skip the inset part and use face centers.

Edited May 26, 2010 by Bruce Hart

[mattclinch]

...Extract the operand sphere and use polygon inset (by polygon) to create faces in between the newly created scatter objects and detach them (see polys in red in image). Get your second array object and scatter them on these new detached faces, this time by face centers...

 

could you not use the same operand sphere and just do the second scatter by "all edge midpoints" instead of having to inset them?

[Bruce Hart]

Yes you could - sorry. It's been a long day.

[Sassmouth]

Thanks very much, Bruce (and Matt).

 

Steve

[Sassmouth]

Hi, Bruce. Can I bother you with one more question about this?

 

I was easily able to create this shape using "scatter," arraying objects on midpoints and vertices. But I've noticed that there seems to be two subtle things I can't get rid of. As you can see in the attached image, the green boxes become compressed around the middle of the geosphere, and stretched at the top and bottom. They are set to a uniform scale though. Do you know how to make them all appear uniform?

 

The second thing is that as they are set to perpendicular, because they're perpendicular to the faceted geosphere, their resulting orientation is slightly wonky angles. When I tried to first smooth the sphere, it created too much extra geometry.

 

Thanks again, I appreciate the input.

 

Steve

 

[ATTACH=CONFIG]37321[/ATTACH]

[Bruce Hart]

Hey Steve,

I'm not sure what's going on here. I was just using regular box and pyramid primitives to scatter. There was no distortion evident. I see your blue pyramids are OK. I only got distortion similar to your picture, when I scaled the scatter box in one axis. If I applied a reset Xform to the scaled box it scattered perfectly fine with no wonky angles. You may wish to try this on your scatter objects.

 

What's this for anyway? I'm guessing you're making a modern sphere lamp, a sea mine, or your doing something with microbiology

 

Hope this helps

[Sassmouth]

Hi Bruce.

 

Thanks for getting back to me. I think I figured it out, but I'm not sure why it's happening. When I just draw a geosphere, then a box, then scatter that box over the sphere, it arrays perfectly spherical with no distortion. BUT, if I then edit that box, it goes haywire. Also, if I simply "undo," and revert to just box and geosphere and re-try... it comes out distorted again. It seems like it only works as a one-off. I tried applying a reset Xform, but no luck. Maybe it's my computer? Graphics card? Shouldn't be though.

 

Anyway, I like that modern lamp idea, and if there were a market for marine mines, I'd be set. Your 3rd guess is right--it's a flu virus. I'm just making the image for fun (I'm an unemployed architectural renderer whose trying to expand his marketability). This is the near-final image, attached. Thanks again for your input, I do appreciate it.

 

Steve [ATTACH=CONFIG]37338[/ATTACH]

[Bruce Hart]

Hey Steve,

yeah the distortion will always happen if you try to alter the box after you scatter it (being an instance copy). I guess that's just how it works with the vertex movement, being relative to the orientation of the first scatter box made. I was editing the box and resetting the geometry before doing a completely new scatter operation. It's not your computer or graphics card, I think it's a case of the vertex movement being relative to World Space as it is arrayed, as opposed to moving with the local object space orientation of the box - hence the distortion. (if that makes sense)

 

It's good to try unusual stuff like that. I've done some character and car models myself just to improve my poly modelling skills. You can always discover new little tricks that are useful in your day-to-day Arch Viz work. Next time you need to make a funky sphere lamp - it'll be a breeze

 

Your virus looks cool with the DOF and quite deadly.

 

Cheers

[Koper]

a bit OT

 

So how do you fix the current transforms pivot of an object without attaching to a new object? If I scale an object by 200 units and looking in the hierarchy tab you have two reset options - reset pivot and reset transforms,scale, and the latter works, but I want the reset pivot to be the same, as when you use reset pivot you'll find that the scale is back to 200. I want the new scaled transforms fixed to the object.