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[Blender] Why won't subdividing smooth my mesh?

polycounter lvl 11
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daniellooartist polycounter lvl 11

I'm using a subdivide modifier. I set my edge creasing to be a factor of 0.5 to give the edges of my bevel a little bit of smoothness. When I add the subdivision modifier and use the catmul clark method, all I see is geometry being added. It does not smooth my geo like it would in Maya. How do I do this?


UPDATE

The issue is not yet solved because I don't understand the solution. My solution was to just play around with the quality and the viewport options. I don't understand what quality actually does. According to the doc,

When Use Limit Surface is enabled this property controls how precisely vertices are positioned on the limit surface (relatively to their theoretical position of an infinitely subdivided mesh). It can be lowered to get a better performance.

Using higher values does not necessarily mean real improvement in quality, ideal results might be reached well before the maximum Quality value.


So who is good at explaining this? I know I'm asking for a lot, but is there some visual aid that can explain how these two settings should be thought of in terms of how they quarilate with each other. Because it just feels like I'm throwing darts at the wall until something sticks. Thanks :)

Replies

  • okidoki
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    okidoki triangle

    To be honest: your screenshot doesn't tell me anything (and i also don't understand like it would in maya...). I even don't understand your workflow because any bevel modifier and subdivision modifier would not produce such a topology on a cube.. (different grid on main faces and smaller on side ???) I also do not see any creases (shown in violet in my screenshot).. and it doesn't make any sense to set the subdivision to 8 in the viewport and 1 in the render (which defaults to 1 and 2).. 🤷 Maybe a screenshot from your original mesh and the creases can show the problem and/or your original intention or the wanted result is better described with another image.

    From left to right Cube, beveled Cube ( in front simple subdiv'd beveled Cube ), subdiv'd (catmull-clark) beveled Cube, subdiv'd beveled Cube with creases 0.5 (Using blender 3.2.2 under linux but 3.3 shows the same UI):


  • lluc21
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    lluc21 polycounter lvl 4

    My only idea on what is happening is that you have a crease value of 1 added to every edge. Try disabling Use Creases in the subdivision modifier and see if that fixes the issue. I you have a crease value of 1 in an edge you will see it highlighted in purple/pink when in edit mode.

  • daniellooartist
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    daniellooartist polycounter lvl 11

    Short version of the question. What is the subdivide modifier quality parameter actually DOING?

    Long version of the question. If I want an edge crease in my model, why do I have to fudge with both the crease tool AND the quality tool to get the results I want? I don't know how much experience you have in Maya, but if you want rounded edges in Maya, you use a low crease and subdivide. If you want sharp edges, you would add a high crease value and subdivide. It's literally that simple.


    I don't have much experience in Blender so I don't understand why this extra step of setting a "Quality" is even necessary. Low quality values make things smoother apparently but why would you NOT want your edge roundness to match the set crease value exclusively?

  • daniellooartist
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    daniellooartist polycounter lvl 11

    Here is a second image to further illustrate my confusion. My monkey brain is too stupid to figure out the pattern here. Can anyone else explain the pattern between different subdiv quality values at different crease factor values?



  • okidoki
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    okidoki triangle

    First: if you have a subdiv of 5 then the quality is irrelevant and if you have no creases then you don't get cubes like you showed and if you have crease of 1 then this means no catmull clark smoothing at all... so what do you want to show here ??? 🤷 (Maybe you are overthinking this??)

    Anyway: Why bother about any advanced features if your result may be better done by just using a simple bevel (shift-b) with segments (mouse wheel).. ?? (and i just uesd 4 subd and forgot the s ): (( ...you could also use the bevel modifier with a segments parameter of 3 or more and smooth shading if you want this change this ))

  • daniellooartist
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    daniellooartist polycounter lvl 11

    The reason I want to use edge creasing is because I would like to build things for tessellation. Ideally all of the polygons should be 1:1 in size. Bevels are too thin.

  • okidoki
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    okidoki triangle

    Okay.. i don't completly get it.. (..bevels are too thin / but first image shows beveled cube ..? ) maybe just show an example like you want to have it ?? Because i still can't decipher what your first image want us/me to show.. And as i said i don't know/understand what you mean by: like it would in Maya. The workflows just seems to be different so we both can learn something.. or this is just overthinking on one or two sides here ??

  • daniellooartist
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    daniellooartist polycounter lvl 11

    Sorry. The first image was not the best example. But yes, I do not understand the quality parameter.

  • okidoki
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    okidoki triangle

    I maybe nether.. but who cares ?? Other software may don't even have a quality/precision parameter.. so if less value means less quality but faster (see popup text) and you can't see a difference on the things you do.. then what ? Just remenber that there is an Advanced submenu.. so maybe some time in the future.. And still you haven't shown what it is like in Maya so you want to copy this workflow/look.

    Anyway: you could also use two subdiv modifier on with simple and one with catmull so you get the tessalation thing you want ?



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