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CarlBjorndal

Smooth subdivision on one axis only

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Hi. I have tried to find a way to do a smooth subdivision on one axis only.

 

For example, say you have a cylinder and you want to do a smooth subdivision on only the polygons that... hm how to explain, I add a screenshot for clarity.

 

Thanks in advance,

Carl

smooth_on_one_axis_only.jpg

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Rectro    475

Hi

 

Sub division is not what your after, it will always sub divide by 4x on all axises.  You need to use the Loop path cut modeling tool, or put the correct segments while its still a primitive object from the Object manager.

 

Dan

loop slice c4d.jpg

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Thanks Dan for the reply.

 

Well, smooth  subdivision is actually what I am after. The cylinder in my example was only a simplified visualization showing the issue.

Doing for example the edge cut tool (ngons unselected), one can subdivide, but not in a smooth manner. What I am thinking about is in a more complex situation, 

I have seen this question asked trough out the years on different forums, but I can not seem to find a adequate  answer.

 

Carl

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Rectro    475

If smoothing is what your after but with a certain control over the topology, maybe try to the smooth modifier allow with cut tool?

 

Dan

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Thanks for your effort Dan. You know, it is basically a full object smooth subdivision where one can control the subdivision on V or U direction.

But perhaps that is impossible within the smooth subdivision algorithms.

 

 

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Rectro    475

Im trying to work out why would you would need to smooth on one axis only for, in what situation?  When I want smoothing in one axis I use bevel.  You can use a vertex map to control the smooth modifier as a stiffness map.

 

Dan

smooth modifier.jpg

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In any given situation where the topology is smooth enough in one direction but not the other.

I mean, sometimes you do a full object smooth subdivision and perhaps you  get way to many polygons, so you manually delete/melt them.

Where as if you could control the smooth subdivision on the different directions you would not need to do all the manual work afterwards.

 

But maybe this is not possible to solve, you see, I have read post from 2005 or earlier asking about this, and I have always wondered why this seems so hard to implement.

 

It is basically a timesaver in situations where your object needs a smooth subdivision, but as in my simplified example, you only really need it in one direction, or perhaps you want to subdivide more in one direction then the other...

 

The added image is trying to show what I mean, the red line is sufficient and smooth, the blue one does look a bit corse, so, If I want to do a smooth subdivision on this object, it will fix the coarseness of the blue but it will make to many polygons in the red direction...

 

/C

smooth_on_one_axis_only2.jpg

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Cerbera    1,023
23 minutes ago, CarlBjorndal said:

The added image is trying to show what I mean, the red line is sufficient and smooth, the blue one does look a bit corse, so, If I want to do a smooth subdivision on this object, it will fix the coarseness of the blue but it will make to many polygons in the red direction...

 

/C

smooth_on_one_axis_only2.jpg

As has been said, this problem is arising because there is far too much topology in one direction - in the example above roughly 50 times the amount required to hold the shape I'd guess. Coupled with the insufficient segmentation in the other direction, any further subdivision is doomed to fail for the reasons you mentioned. This is a very good illustration of why even segment modelling is so important. Because there is simply too much topology here to practically manage, the best option in this example would be to start again, using a swept spline with an n-side as the profile and doing the scale variation with sweep scaling, allowing you to precisely adjust segmentation in both directions.

 

CBR

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Yes, CBR, I agree on your points.

 

But you should see this specific shape as an exaggerated illustrated example only, as the image on the first post, also very simple form to try to explain what I am meaning with the different directions.

 

The question is if it is possible to do a smooth subdivision in one direction only, or different amounts on different directions.

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Cerbera    1,023
1 minute ago, CarlBjorndal said:

The question is if it is possible to do a smooth subdivision in one direction only, or different amounts on different directions.

Well the answer to that is no, or at least not automatically. When I inadvertently find myself in this situation I just go in with the loop tool and add loops where I need to in order to even things up. Doesn't usually take that long, so I don't find myself yearning for better ways...

 

CBR

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bezo    400

just few clicks...

59bed59735746_1direction_smooth.thumb.png.cd009b57969311aafb4ded5540829df2.png

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