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Tony3d
04-16-2010, 07:33 AM
Ok, this is driving me crazy. I can't for the life of me get these results. How does one model these spheres to go up into that spider design evenly, so they all look exactly the same. this is driving me nuts! Can anyone help me with this? I've been modeling for many years, and it suprises me sometimes how little I actually know.

eblu
04-16-2010, 09:17 AM
I would probably bridge two sets of edges (one a deleted poly in the sphere, the other a deleted poly in the triangular hub) for each arc, then use bandsaw pro to subdivide it once and then pull the new points up to add the arc.

assuming I'd be using Sub-ds or maybe subdividing in some other way, down the road.

sandman300
04-16-2010, 11:04 AM
If I were trying to model what you have in the picture. I'd model 1/3 of it and them radial array it.

Tony3d
04-18-2010, 09:51 AM
I would probably bridge two sets of edges (one a deleted poly in the sphere, the other a deleted poly in the triangular hub) for each arc, then use bandsaw pro to subdivide it once and then pull the new points up to add the arc.

assuming I'd be using Sub-ds or maybe subdividing in some other way, down the road.
I really like this idea, but am not quite following the bandsaw thing. Can you elaborate on that a bit with maybe a sample or two. Thanks much.

Tony3d
04-19-2010, 01:23 PM
I really like this idea, but am not quite following the bandsaw thing. Can you elaborate on that a bit with maybe a sample or two. Thanks much.

I don't get it, and this looks like crap. Need a Tutorial I guess.

JeffrySG
04-19-2010, 03:02 PM
Something like this might get you started. You could make the balls bigger or smaller and adjust the bridges as well.

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probiner
04-19-2010, 07:40 PM
I think this video Jeffry did has the right mentality. http://www.pixelandpoly.com/video012.html.
Subdivision modeling can be very tricky since shape and topology are two concerns you need to cover and when you work for one, the other is probably getting wrong so you need to keep correcting it. That's why Retopology is great, because you can worry about the shape and then about the topology.

84185

For the Semi-Sphere i would do something like in the first 2 images. Keep the Sphere centered to the origin, edit all you want in the connection area (topology), then run 'Spherize' (you better use 1m sphere) to keep whatever you have done as a sphere (shape).
I would avoid to have any 5 polygon vertices in those areas where shapes blend (spokes, central cylinder), so i keep them away with and extra edge loop.

I used patches for the spokes, seemed to me the most controlable solution.

For the patches (internal points) and some other situations (edge loops), 'Smooth' can be great to correct shape after you are done with topology, but keep an eye on everything cause it can mess with points in way you didn't intended.
Swift Edge Loop from TrueArt.pt (http://www.trueart.pl/?URIType=Directory&URI=Products/Plug-Ins/SwiftEdgeLoop) can also be great to edit the control edges without messing with the shape.
Line Up Points (http://www.artssphere.com/plugins.php) is also nice, again, to make some shape clean-up.

Here is a quick try.
84184
84187

Cheers

Tony3d
04-20-2010, 12:58 PM
Thanks this was very helpful. It's not perfect, but much better than what I did the first time. Thanks Again.



I think this video Jeffry did has the right mentality. http://www.pixelandpoly.com/video012.html.
Subdivision modeling can be very tricky since shape and topology are two concerns you need to cover and when you work for one, the other is probably getting wrong so you need to keep correcting it. That's why Retopology is great, because you can worry about the shape and then about the topology.

84185

For the Semi-Sphere i would do something like in the first 2 images. Keep the Sphere centered to the origin, edit all you want in the connection area (topology), then run 'Spherize' (you better use 1m sphere) to keep whatever you have done as a sphere (shape).
I would avoid to have any 5 polygon vertices in those areas where shapes blend (spokes, central cylinder), so i keep them away with and extra edge loop.

I used patches for the spokes, seemed to me the most controlable solution.

For the patches (internal points) and some other situations (edge loops), 'Smooth' can be great to correct shape after you are done with topology, but keep an eye on everything cause it can mess with points in way you didn't intended.
Swift Edge Loop from TrueArt.pt (http://www.trueart.pl/?URIType=Directory&URI=Products/Plug-Ins/SwiftEdgeLoop) can also be great to edit the control edges without messing with the shape.
Line Up Points (http://www.artssphere.com/plugins.php) is also nice, again, to make some shape clean-up.

Here is a quick try.
84184
84187

Cheers

eblu
04-21-2010, 03:07 PM
tony3d,
I made a real quick LWO that shows a progression of MY approach to this challenge. each layer is labeled with the modeling procedure, download. play. ask.

ps. Catmull Clark sub-ds for this one, gentlemen.

eblu
04-21-2010, 08:59 PM
ps. I took it a little farther, and found that when I built the top for the hexagonal center, I really wanted to NOT have the beveled arches. I could get a really clean line by selecting a few of the side polys on the arch and then running bandsaw pro, with 2 divisions (one at 10, the other at 90) this crisped up the edge of the top, the arches, and made really nice transitions out of the spots where the arches meets the "feet"

Tony3d
04-21-2010, 10:06 PM
Thanks so much for taking the time to do this. I will check it out the first chance I get.



tony3d,
I made a real quick LWO that shows a progression of MY approach to this challenge. each layer is labeled with the modeling procedure, download. play. ask.

ps. Catmull Clark sub-ds for this one, gentlemen.

probiner
04-22-2010, 04:19 AM
I like your approach eblu, it's light. CC rocks =)

Anyway Im just going to restate why the approach on Jeffry's video is so cool because i think it's usable for many other situations.
Basicly if you want a shape to fuse into another in Subdivision, you have to adapt the topology of each in the connection zone and also make space for 2 extra control loops to give the intersection some sharpness. With this mentality you can connect lots of stuff.

In this example i had to use a boolean first. After getting that sharp look, control loops can be loosen, or even deleted to change the smoothness of the connection.
Spherize again had a important part in keeping the sphere correct after tweaks.
I wish there was a way to edit a shape and then hit a button and snap the new topology back into the original shape.
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http://i153.photobucket.com/albums/s202/animatics/Lightwave/th_cube-shoved-into-a-sphere.png (http://i153.photobucket.com/albums/s202/animatics/Lightwave/cube-shoved-into-a-sphere.png)

Cheers

eblu
04-22-2010, 09:49 AM
Hey Probiner,
I just watched Jeffery's vid. Lots of neat info in there. I don't think it would have changed my approach, though. I just don't see this object as "Pushing different shapes together." To me its a "connect two shapes with a bridge." kind of challenge. and While you Can use part of Jeffery's technique to control the cross section of the bridge, in this case I feel its unnecessary.

heres an image of my slightly more advanced object:

Tony3d
04-22-2010, 01:10 PM
Hey Probiner,
I just watched Jeffery's vid. Lots of neat info in there. I don't think it would have changed my approach, though. I just don't see this object as "Pushing different shapes together." To me its a "connect two shapes with a bridge." kind of challenge. and While you Can use part of Jeffery's technique to control the cross section of the bridge, in this case I feel its unnecessary.

heres an image of my slightly more advanced object:

Yes, this was a big help. I can't wait till 9.6.1 comes out. thanks again for your help. using nurbs is very new to me, and I find it fascinating.

eblu
04-22-2010, 01:43 PM
no problem tony,
the main thing to keep in mind when sub-d modeling is the idea that you are actually building a "generalized cage" and that through a process of "erosion" it will get more complex, and smoother.

This makes it easy to Imply shapes with very few polys, Unless you need to crease something sharply.

It also means that your sub-d object will be slightly smaller. The Smoothing process averages out all the points to generate the subdivided mesh, and in doing so, takes away some of the significant values in your mesh.

being a "cage", sub-ds work Better when tied off in a grid. triangles work too, but you get better results if you stick with quad polys.

and finally, point order Matters. when you draw a poly with the pen tool, it Matters which way you draw it (right handed or left). That indicates which side of the poly gets the normal (which side renders... unless you cheat). There is a similar thing in subDs. in a mesh, you may have a nasty looking topology that can be fixed by "spinning the quads" this is just a function of changing which point is the First point, in the poly. and it Matters with a capital M.

the rest is just technique.

Tony3d
04-22-2010, 02:01 PM
Thanks again. If I have other questions, do you mind if I PM you? I can model almost anything if it's not organic in nature, but I have trouble with this sort of thing. What did you think of my attempt at it up the tread a bit?


no problem tony,
the main thing to keep in mind when sub-d modeling is the idea that you are actually building a "generalized cage" and that through a process of "erosion" it will get more complex, and smoother.

This makes it easy to Imply shapes with very few polys, Unless you need to crease something sharply.

It also means that your sub-d object will be slightly smaller. The Smoothing process averages out all the points to generate the subdivided mesh, and in doing so, takes away some of the significant values in your mesh.

being a "cage", sub-ds work Better when tied off in a grid. triangles work too, but you get better results if you stick with quad polys.

and finally, point order Matters. when you draw a poly with the pen tool, it Matters which way you draw it (right handed or left). That indicates which side of the poly gets the normal (which side renders... unless you cheat). There is a similar thing in subDs. in a mesh, you may have a nasty looking topology that can be fixed by "spinning the quads" this is just a function of changing which point is the First point, in the poly. and it Matters with a capital M.

the rest is just technique.

probiner
04-22-2010, 02:36 PM
Eblu, what i liked in your previous example was the fact you used beveled corners instead of sharp i used, and your mesh was very light.
Well it's normal we see things differently.
I used spline guide over a tube this time to control the curve of the spokes.

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84277

Cheers

eblu
04-23-2010, 07:19 AM
Thanks probiner!
I like to see how different people approach the same problem too. In 3d theres's always something to learn from others.