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randysolo
04-11-2006, 12:38 PM
I'm having a problem with holes. Not round holes, but square holes. I need several square holes in the top of a metal cap or cover. I can make the holes but with I hit tab, it makes them round. I tried bandsawing but it doesn't help.

any ideas?

Powersolo

randysolo
04-11-2006, 01:12 PM
here is the sequence.

randysolo
04-11-2006, 01:56 PM
AMAZING!! That worked like a charm. The edges come out a little rough but I need to work on my geometry a little too. I had no idea you could do that. I use Silo on occasion and Wings. Is this sortof equal to "Hard edges" Is there anything about the map I should know or do I need to expect any surprises? I like this!! I learned something today!! Thanks!!

Powersolo

soioartist
04-12-2006, 01:00 AM
thanks bryphi!
i was just browsing trough the forums when i discovered that handy tip!
greetings

randysolo
04-13-2006, 06:22 AM
Hey... I've got another modeling problem... can you help with it too?
thanks,

Powersolo

Captain Obvious
04-13-2006, 09:09 AM
You can also add extra geometry around the edges to tighten them. Like this:

randysolo
04-13-2006, 09:26 AM
..that's true. I tried adding geometry but I kept creating more work. I'm wondering if the booleans in LW9 are going to handle a lot of these hole issues without so much patching. I'll be happy!! I need to make a photo of something else I need help with. It's also hole related. I'll do it after lunch. Thanks for your help.

Powersolo

Captain Obvious
04-13-2006, 10:06 AM
Well, LW9 will have CC subd's and they support ngons, so that would have definitely made life easier for you...
Not all that much easier. Ngons are still best avoided, as they can produce funky-looking geometry. I'm also told they animate poorly.

eblu
04-13-2006, 10:30 AM
and there are MANY ways to add geometry to your model than what it sounds like you've tried.

you could bevel the polys inside the hole. you could smooth shift the inside polys and scale them down slightly. you could edge bevel the corners. I haven't covered all of them by any means, but Any one of them will be better for you than using subpatch weights. that can cause an unwanted sharpening in other places, on the model.

randysolo
04-13-2006, 01:39 PM
Here's my other problem. I'm really learning alot this week. Except for spelling. Anywho, I'm posting 3 images. the first 2 are photos of the product. I'm trying to get the holes that are in the curve surface. Again, I think booleans in 9 would help with this. Where I'm using these holes, the are won't be very large. I wan't to add animation to these, but in some cases they will be covered up. Never the less, I'd like to experiment with different methods and try to get my geometry cleaner (I'm a mess with it!!) That will take time I suppose.

thanks for your help,

Powersolo

randysolo
04-13-2006, 02:16 PM
I'm still a rookie. I forgot about splines - thank you! I get in the sub-d mode and can't get out sometimes. I'll try the splines and see how it works. I guess I haven't really worked out a work-flow for splines - like you said - plan out the model. That happened to me twice today. I modeled something from a cube, trashed it, then from a disc, trashed it, then and spline and lathe - perfect. I never know which method is the best until it doesn't work. I guess experience is the only medicine for that. Thanks for the advice though. I'll try to post the results.

Powersolo

Captain Obvious
04-13-2006, 02:17 PM
One lazy way of creating that is to model the whole thing except the holes with subpatches, then freeze the model and boolean out the holes. It makes it really hard to edit afterwards, but it's a piece of cake to model.

randysolo
04-13-2006, 02:22 PM
Thanks captain, I'll try that method too. I wish I could model vases or something.... cheers all,

Powersolo

Captain Obvious
04-13-2006, 02:48 PM
Remember to save a backup of the un-frozen mesh! ;)

randysolo
04-13-2006, 03:21 PM
Sure give it a whirl. I had to reduce the size of the top photo. It should be the same width as the front.

thanks for the help,

Powersolo

randysolo
04-13-2006, 03:26 PM
I'm having trouble uploading.

randysolo
04-16-2006, 07:06 AM
Any luck Bry? I haven't had a chance to get back to it this weekend. I was going to just do a spline patch of just the cup with the hole going side-ways. Now I'm thinking of doing the whole thing as a spline patch.

thanks,

Powersolo

eblu
04-17-2006, 12:36 PM
ok, you're modeling an organic object and you find the need for some sharp creases, edges, or well defined shape. You instinctively know that Sub-Ds aren't necessarily the Best approach to these shapes, but you have your reasons for doing it this way, and you know that there Must be a way to get out of this corner you painted yourself into.

what can you do?

well lets explore that. I myself would model the object's shape, and then freeze it, and boolean out the sharp parts, but there is something very nice about modeling in those details. I've used the sub patch weight thing in the past and I feel that it has limits to its utility, and to my eye, its not as good a render than actually modeling in the detail itself.

so you go through the motions and you get a square hole in your surface (fig a), all made from quads (so that it will sub-D) then you hit the tab, and your nice square hole becomes a circle (fig b). We all know how to fix that right? just add a knife mark, ever so close to the edge of the hole (1 knife mark on each edge) and that will smarten the walls of that hole right up. But what if you have multiple holes all lined up in a grid? that can make a heck of a dense mesh, and it may not even solve the problem at all...
lets see what else we can come up with...

First, I have to say that relying on N-gons, is a mistake. the best surface you can build for sub-Ds is a quad surface. 4 point polys ALWAYS work the way they should. in a pinch yopu could use 3 point polys, but they can have issues on some complex surfaces. It is ALWAY possible, and GOOD to exclusively use 4 point polygons with sub-D surfaces. Obviously in the real world its not always worth it to fuss, but if you are learning... you can do no better than to get in the habit of using 4 point polys exclusively.

fig C.
select the interior polys of the hole and multishift them, a very little bit, and you get a round hole, with a defined edge. interesting but we wanted a square hole didn't we? well, at least we didn't generate a trail of polygons all the way around the model.

fig D.
ok, take the model from fig C. now select the points on a corner of the shifted polys (a total of 2 points) and edge bevel them, a very tiny amount. This leaves you with triangular polys at the corners, so its not ideal, but it is very effective. (triangular polys sub-d just fine, but they don't always look good)

fig G. (yeah I know its out of order, sue me)
if you just take the original hole, and bevel it, you can get "passable" results by beveling the inside polygons. you can see the obvious dimpling in the corners, so I'd only use this on something I'm never getting that close to.

fig. E
now we're getting somewhere! this is pretty interesting.
What you see here, is a multishift. 4 of them actually. select an interior polygon of the hole, and a polygon on either side, and multishift it, ever so slightly. the less you shift, the more sharp the crease. then do the same thing to the remaining 3 sides, you'll find that you can get some respectable corners rather quickly. The only problem is... that the hole doesn't have a nice flat interior....

fig F.
if you take the hole from fig E and select the interior polys, you can then multishift them, and get a really nice hole.

Why is this better than subPatchWeight maps? presumably, you will NEVER model this kind of detail UNLESS you are right on top of it with the camera, its just not worth it in the long run. So, if the camera is going to be right on top of it, you want the best specular highlights, shading, and smoothness you can get, subPatchWeights, create render glitches, they are difficult to control (sometimes creating radial tension, where you can't fix it) and they always lack the sexy specular hits you WILL get by modeling in the detail.

randysolo
04-17-2006, 12:54 PM
Wow! I'm amazed at the all the help at this place. I'll give that a try also.
Thanks again,

Powersolo

randysolo
04-17-2006, 06:02 PM
Actually the results of F look fine. Especially if they will a.render without glitches and b.give sexy speculars. I haven't tried to render the subpatch weights yet (still or animated) but I want to compare the two. For what I'm using this for it may not make a difference. This cap or lid is part of a larger machine with about 20 or 30 other parts. If, like you say, there will be glitches, it might not be what I want if it's too distracting when the machine moves. Is there a way to render, with subpatch weights, and keep this to a minimum? Or am I better off redoing the cap and modeling in the detail. I'm really enjoying this project! I didn't expect this amount of response.

thanks,

Powersolo