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madno
08-05-2017, 02:44 AM
Hi,

again a modeling question.
Difficult to explain.

I have a cockpit hull which now needs to be detailed.
As it is a sub-d object it has nice curvature.

Now I want to make the window frame by deleting inner polygons from part of the hull.
But because the model is low poly at the moment, I only have one loop left after deleting the inner polygons.
That of course kills the nice subtle curvature.

137574

So question is, what is the best way to keep the curvature without getting to much geometry?
The only solution I found is "Subdevide with Metaform option enabled".

Just like to ask are there other ways?

hrgiger
08-05-2017, 02:52 AM
In Lightwave, there is nothing built in to deal with this. Other tools like Modo (and maya maybe?), have a preserve curvature function built in. If I am doing this in LW, its pretty much just tweaking it manually.

https://media.giphy.com/media/l41JMvoxU9VxsEOBy/giphy.gif

pinkmouse
08-05-2017, 03:15 AM
There was a plugin for windoze that helped with this, but it never had a mac version so I don't know if it's still around or working with current LW releases.

Ztreem
08-05-2017, 04:18 AM
This is why you use Nurbs when modeling things like this for real products. But if you want to add details in sub D and try to keep the curvature ( it will never be exact as that is almost impossible with this tech). you can freeze your geometry to another layer and use heatshrink to move the points of your new more detailed subD model to the same position and then you have to tweak it by hand.

prometheus
08-05-2017, 04:25 AM
lwcads new tools perhaps, additionall cost, otherwise not sure..maybe edit edges.

Reco
08-05-2017, 05:04 AM
LW cad nurbs does not support Boolean at the moment.
Best option inside LW is Catmull Clark using edge sharpness, but it will only work inside LW.

This is a good example where Open Subdiv would have been useful. (Max video below from 7:15)
https://www.youtube.com/watch?v=QFckVSyvVy4

Reco

madno
08-05-2017, 05:29 AM
Thanks for input. In the end it was the subdevision tool with metaform option and then pushing points and edges like a mad man. At least I have a starting point now (took me ages to get there).

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Surrealist.
08-05-2017, 05:55 AM
Hi,

again a modeling question.
Difficult to explain.

I have a cockpit hull which now needs to be detailed.
As it is a sub-d object it has nice curvature.

Now I want to make the window frame by deleting inner polygons from part of the hull.
But because the model is low poly at the moment, I only have one loop left after deleting the inner polygons.
That of course kills the nice subtle curvature.

137574

So question is, what is the best way to keep the curvature without getting to much geometry?
The only solution I found is "Subdevide with Metaform option enabled".

Just like to ask are there other ways?

I find there are a lot of issues other than just this when it comes to making complex objects with subD. Planning in advance is the best way. Hand adjustments where needed, as hrgiger points out. Part of the advance planning is to try and determine the level of density you will need in your base mesh.

For example. If you are making just a small cylinder, you can get away with something like 8 to 12 sides. But with a large hull of an aircraft you would want to start with something like 32. Depends on the detail you will make. This gives you more options to step down your high detail to the base grid mesh.

Here is a simple example:

A lower dense base mesh has some other issues:

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The above example will give you problems that look like this:

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But if you start with a more dense mesh:

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The result will be much more stable:

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Another thing to keep in mind is to model things as they are in the real world. In parts. This way you are not trying to connect everything. Faster and much more stable.

Edit: I see you are moving in the right direction. Hope this helps.

madno
08-05-2017, 10:31 AM
Thanks Surrealist,

you mentioned to model in parts some time ago in another thread. Without doing that I would'nt have been able to get to this point at all.

Surrealist.
08-05-2017, 10:43 AM
Great. Good to know. Thanks for the update. Model looks real good. :)

jeric_synergy
08-05-2017, 10:53 AM
BTW: IIRC user Probiner has a number of extremely helpful graphics on his site that illustrate various configurations of quads to make nice transitions, and that show how to step up/step down from various levels of subdivision to other levels.

URL most likely in his .sig.

djwaterman
08-05-2017, 11:15 AM
I like that space ship, looks like you learned fast.

madno
08-06-2017, 01:19 AM
BTW: IIRC user Probiner has a number of extremely helpful graphics on his site ....

Thanks, found them. He even made SWF files out of them. Now part of my desktop looks like this ;-)

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jeric_synergy
08-06-2017, 09:07 AM
Awesome! They are very helpful, rather than having to 'reinvent the wheel' over and over.

Surrealist.
08-06-2017, 10:13 AM
Yeah I agree. After a while it becomes second nature but it is real handy to have them. I think there are some links to things like this in the workshop in my sig as well.

Here is another resource:

https://pixelandpoly.com/video.html