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madno
10-18-2015, 01:50 AM
Hi,

does anybody know a web place where I can study mesh examples from sub-d models with window insets? You know something like car doors or space ship things. I know about the basics like stabilitzation edges etc., but would like to "borrow" some ideas from those who really know.

130397

Oedo 808
10-18-2015, 01:59 AM
I'm not sure about specific examples, but you might take a look at Surrealist's Fundametals of Subpatch Modelling (http://lightwiki.pro/wiki/Fundamentals_of_Subpatch_Modeling) tutorial on LightWiki. Part two with the loops on lettering might be of particular interest.

madno
10-18-2015, 03:34 AM
Thanks for that one.
I like to explain where I am struggeling. My idea in the sketch is a curve for the front side of the vehicle, but looking at my first model attempt I don't think I will get there. So I thought I can watch solutions of others. I have seen some so far, but those are mostly very highres and often with tris. I am trying to find a lowres start that is suitable for the sketch.

130400

raw-m
10-18-2015, 03:39 AM
I would suggest setting yourself up a Pinterest account. Do a search, loads of fantastic inspiration. It can be general to all 3D apps and a lot of meshes are posted, too.

madno
10-18-2015, 04:19 AM
Yep,
definitely a lot of pins there,
thanks.

JoePoe
10-18-2015, 09:02 AM
I think you're fine for that to be a smooth curve. What happened when you hit SubD??

See? A smooth curve.... 130407. The problem is the bulge in the front from the highlighted edge. Actually it's the proximity of all three of those front edges. Or maybe that works for you with the window in the front...

Ideally though, (and in order to fix the bulge) I would.....

add these.... 130408

dissolve these.... 130409

then Multishift... 130410. But you can do the fix after the multishift too.

Edit: Also, It does look like you're missing the other side of the control loop pairs at a bunch of corners.

jeric_synergy
10-18-2015, 11:30 AM
JoePoe is a past master at fitting subds in, but a more general question, si vous plait: Since the holes in a mesh are often the sticking point, wouldn't it make sense to start with the windows and model outward? It's the retro-fitting of holes (or near-holes, like the windows) that take a lot of head scratching, whereas making a nice subd hole or recess without the bulk of the mesh is a breeze.

I suspect we are so used to the physical world and "roughing in" a shape with clay or wood and proceeding to details that we neglect the particular needs/properties of the virtual world. Putting up a big wad of material is tough in the real world, all too easy in the virtual world, whereas drilling a smooth hole is a piece of cake in the real world, but can be hair-tearingly frustrating in the virtual world. (Or at least a bit of a puzzle, as above.)

Surrealist.
10-18-2015, 12:02 PM
Additionally you can look here for examples:

http://forums.newtek.com/showthread.php?83878-Subdivision-Modeling-Workshop

on Page two we started talking about car modeling:

http://forums.newtek.com/attachment.php?attachmentid=58805&d=1210706084
http://forums.newtek.com/attachment.php?attachmentid=58806&d=1210706090
http://forums.newtek.com/attachment.php?attachmentid=60124&d=1214278242

Lewis
10-18-2015, 03:01 PM
Well for a start you have too low geometry and it will cause you problems and visible pinching when you start adding cuts/seams and sharper edges. People often make mistake and start with subDs from Biggest flat arweas (whcih is cool at first since you see progress much quicker at beggining) instead starting form most dense areas to se ehow much polygons/details you need there. It's easier to remove detial/polys in later than add them on to already msooth areas/mesh. For isntance for a car models i usually start polygons form a wheel arches and then i can see how much polys will my fender and bonnet have. If i start from Bonnet i need very little density but then that makes the problem on wheel arches sinc there is not enough polys to make it properly circulaar wihtout visible segmentation and problems.

So in your case I'd subdivide all once to ge tmore density and then go form there. Gratned it woudl be better if it was more density form start but it's doable this way also with some polyogn flatening/smoothign after subdividing.

Surrealist.
10-18-2015, 06:58 PM
Yeah good tips.

Also another one. Model things as they are in the real world. In many cases an object like that would not even be one piece, but made up of various panels etc.

jeric_synergy
10-18-2015, 07:13 PM
In many cases an object like that would not even be one piece, but made up of various panels etc.
MOST cases, most likely.

Surrealist.
10-18-2015, 09:26 PM
Yes, and quite unlike my car example above ;)

Which would be separated in to a few different panels. I think at the time I was mainly just trying to teach the basics of poly flow on a shape.

But the thing is, when doing it as it is in real life, it is actually easier in a lot of ways than trying to make everything as one.

Surrealist.
10-18-2015, 09:27 PM
Yes, and quite unlike my car example above ;)

Which would be separated in to a few different panels. I think at the time I was mainly just trying to teach the basics of poly flow on a shape.

But the thing is, when doing it as it is in real life, it is actually easier in a lot of ways than trying to make everything as one.

Farhad_azer
10-18-2015, 10:12 PM
Thank you so much Richard for mentioning the workshop discussion. I had not seen it and I just found that there are other dark sides in this forum that I and lots of others are missing. I am familiar with your lightwiki page on subdiv and will definitely recommend it, as raw-m, to our friend madno. unfortunately I have not been able to read ur whole lightwiki subd tour but I should do it very soon.

jeric_synergy
10-19-2015, 12:32 AM
I wish very strongly there was an explicit "MODELING" forum here, rather than the "GENERAL" category. Seems like a big oversight.

madno
10-19-2015, 01:06 AM
Thank you all,
great advice. Time to digest :-)
By the way, when symmetry works, the new (LW 11.x) tweek tool is really nice.

Surrealist.
10-19-2015, 08:17 AM
Agreed Jerric


Thank you so much Richard for mentioning the workshop discussion. I had not seen it and I just found that there are other dark sides in this forum that I and lots of others are missing. I am familiar with your lightwiki page on subdiv and will definitely recommend it, as raw-m, to our friend madno. unfortunately I have not been able to read ur whole lightwiki subd tour but I should do it very soon.

Yeah I used to have it in my sig. I'll see if I can fit it again.

One of the problems is the forum search and links have been borked for a long time, baring users from getting at earlier data. To get these threads I have to use Google.

There is a trick to get the old links to work, but I forget what it is. I think Spherical knows.

madno
10-19-2015, 10:11 PM
I think it was about the url:

http://forums.newtek.com/showthread.php

The word "forums" must be in front - in the old threads it is placed somewhere else.

madno
10-19-2015, 11:50 PM
Just want to say thanks again.
I am slowly getting somewhere.

130441

Surrealist.
10-20-2015, 12:46 AM
Wires?

A few things stand out right off the bat. The windows. Looks like they are connected. I would make them separate. And even consider a separate layer with SubD turned off. Like a simple spline cage or something. I mean it does not have to be subD.

And then also it seems as if your vertical and horizontal edge loops are defining the shape too much, making it kind of blocky. If that is intended disregard. But usually you want to stop those loops from defining the shape by spreading them out from the source.

Wires would be enough to advise more specifically.

madno
10-21-2015, 01:30 AM
Thanks for the comments. I fully agree. At the moment the whole thing is "hacked" to get a feeling for the edge loops and how they define the shape. I am sure you gals and guys have a topology already in your mind even before you start to model. I am sitting here and need half an hour to get rid of a tri and then another half an hour to get rid of the ngon I have created by eliminating the tri :-)

My idea for the model is to let it look technical but also with some curves (I am not yet sure if I like the edgy look or not). Later on I like to split it into panels and also separate the windows and doors (hope I ever come to the doors). A long way to go.
If I don't give up and if you don't mind I like to bring it into the WIP forum for more advice ?

130453

Surrealist.
10-21-2015, 12:32 PM
Thanks for the wires. It is good to have a plan. And try to understand that for you this is a process. And even if you are approaching it differently than, say I would, you will come out of the project having learned a ton of things you take on to the next project. And the most sage advice I can give is that modeling requires you do it a lot. Dozens of models at least before things start to click.

But as far as planning goes. It will save you time in the long run to plan in advance what you will model. Another tip is to look at reference images. Even if you are modeling a fantasy vehicle, prop or character, use references in the real world that are similar. Base everything off of something that already exists in how it is constructed or in the case of the character a similar anatomy.

And in most cases this will leave you easier modeling tasks rather than harder. The most common rookie mistake is to make things all connected. (Been there done that). And it is far more difficult to manage edge flow if you do that.

madno
10-24-2015, 10:36 AM
Hi,

sorry, still fighting with the insets. Maybe somebody has an idea how to get rid of the pinching shown in the screenshot? I tried millions of additional edges but have not found the right solution. Appreciate any input you might have.

130539

Relevant geometry is in layer 1 and 2

Lewis
10-24-2015, 10:44 AM
you have too little geometry for such cuts/sharpenings, that will never work without pinching, you'll need to up the resolution of mesh by 1 level or manually add detials/rows of edges before you want to tighten corners.

Check this example. It's old model (i made it 9 years ago) but shows how many areas have increased density for adding details.

madno
10-24-2015, 12:24 PM
Yea,
I finally saw the problem. It needed one more main edge to stabalize the hard angle but still letting me control the smooth bow with the remaining edges. Damn it was so easy, but I needed a day to find it out. I know, still not perfect, but hey, at least a little success :-)

130544

Thanks

Surrealist.
10-24-2015, 03:08 PM
That is actually not ideal poly flow for that set up. Your solution while works is more like a Bandaid. And it also is causing other issues in your model.

You want to follow these basic rules:

http://lightwiki.pro/mediawiki/images/9/9b/LetterA.gif

Found here:

http://lightwiki.pro/wiki/Fundamentals_of_Subpatch_Modeling_Part_Two

And avoid these:

http://lightwiki.pro/mediawiki/images/9/92/LetterA4.gif

You want it like this:

http://lightwiki.pro/mediawiki/images/5/52/LetterA6.gif

And if you look at the edges in the first pick how I sort of fanned them out from the edge. And do like Lewis says, add more general geometry you will have better luck all around.

If you follow the basic principles I outlined here your model will be more efficient and you can control the overall shape much better.

I discuss the solution Lewis is talking about here:

http://lightwiki.pro/wiki/Fundamentals_of_Subpatch_Modeling_Part_Five

Down the page somewhat. Using a 16 sided cylinder as opposed to an 8 sided one.

jwiede
10-24-2015, 03:43 PM
That's the nice thing about sub-d edge weighting, it lets the user restrain geo density where they actually need it for the model, and separates hold/curvature management into its own thing (via edge weighting). In particular, not having to deal with hold edges all over the place generally makes poly flow management a more efficient proposition.

JoePoe
10-24-2015, 03:52 PM
That's the nice thing about sub-d edge weighting,

Yeah. Too bad they're an utter mess (imho) to work with effectively in LW. Unless it's the very very very very last button you hit. Or if it's something super simple (but then you probably don't need them anyway).

Surrealist.
10-25-2015, 12:04 AM
I have not had much luck with it in Lightwave. It is a different technique to be fair. The later versions of pixar subdivision surfaces this has been improved. Maybe this will come to LightWave down the road.

madno
10-25-2015, 11:17 AM
Yep,
go the idea, I think.

130555

But need to start from scratch. The way I made the base shape was wrong. It must have had created non planars (needed to take a sheet of paper and fold it, to see where I went wrong).

Surrealist.
10-25-2015, 02:40 PM
Good Job. I think that polyflow will work much better for you. :)