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How The F*#% Do I Model This? - Reply for help with specific shapes - (Post attempt before asking)

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  • wirrexx
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    wirrexx interpolator
    I made this black object in Blender. While the shape and shading is good, it looks very highpoly for something that will be duplicated 7 times. Is there a better way to do the topology to reduce the polycount while still retaining the shape?


  • abronee
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    abronee polycounter lvl 2
    Hi! I am trying to model this cylinder into a the cube, and tbh Im a little lost on where to start. I could bevel the edges with a high fraction, and boolean a cylinder into that corner, but then I would lose the hightlights, as it gets too soft. Would be a great with a tip, on how to approach this at least! Thanks 

  • FrankPolygon
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    FrankPolygon quad damage
    @abronee There's a discussion about merging similar shapes a few posts up and the last couple of pages of also have examples of how to add intersecting surface features to curved geometry. It's definitely worth taking the time to read through some of the existing documentation in this thread to see if any of those solutions can be applied to the shape in question.

    It's considered best practice to start by blocking out the shapes, matching the segments on the intersecting curved shapes and adding supporting geometry where needed. If you run into any major problems while modeling the shapes: post some images of the mesh in shaded and wire-frame mode, describe the issue, attempted solutions and how you would like to improve the results. Seeing exactly what's wrong with the mesh will make it easier to give accurate feedback on possible solutions to specific problems.
  • tonpix
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    tonpix polycounter lvl 5
    Hello. I'm modeling a bike part and there's a tricky area where 3 curved sharp edges meet at 1 intersection. I'm not sure if it's possible to fully avoid a triangle/ngon. I suppose they might be necessary evil, but I'm not sure how to place them in a way to avoid excessive loops. There was one attempt from me in 3rd picture, but I believe it's not elegant solution :D There's link to blender file if it helps https://drive.google.com/file/d/1akP9WgfKCi07cV99FqY3wA5SLPHkzBv9/view?usp=sharing (in 2nd pic, blue edges are marked as max bevel weight for adding support loops via bevel modifier)



  • Zoddo
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    Zoddo polycounter lvl 2
    @tonpix In this case it would be a lot faster to ignore all the support loops and just bevel your edges upon weight or angle before subdividing your mesh (bevel with modifier and don't collapse it)
    Really you shouldn't be afraid of having ngons or triangles, as long as the end result is what you want visually. You are working on a hardsurface model so you can get away with a lof of ngons.

    since you're using Blender, I highly recommend Boxcutter, HardOps and Meshtools for your hardsurface models as it speeds up your modelling.

    Also the problem why you get so many overlapping lines etc. at this "intersection", is because you try and connect so many vertices into one corner and subdivide it later.
    So what you can do too is make the corner more broad, so that it's not a 90degree corner with one edge. So adding another corner to it so that the overall shape is closer to your end-result when subdiving might also help.
  • IronLover64

    how do I merge these two pieces together into one piece as well as have it on all 4 sides?
  • FrankPolygon
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    FrankPolygon quad damage
    @IronLover64 There's a discussion about a similar shape on the previous page.

    There's more than one way to do this but start by matching the number of segments in the cylinder to the adjacent geometry in the quad sphere. Join the two shapes by using either a boolean operation or a bridge edge loop operation. Clean up any stray geometry before and after joining the shapes. Duplicate the joined features into a quarter shape segment using the split, copy, mirror and rotate tools. Add a mirror modifier to complete the rest of the shape. Below is a basic example of what this could look like.



    It's also possible to use shape primitives and a series of modifiers (array with empty rotation offset, mirror, boolean and bevel) to perform most of the previously mentioned modeling operations in non-destructive manner but for such a simple shape this excess complexity may not make sense. The tools, order of operations and amount of geometry needed will vary depending on how closely the model will be viewed and the desired goals for the project. Adjust accordingly.
  • martianlion
    Hey people!
    Every now and then I face a problem of merging three+ edges with bevels of different sizes applied to them. And every time I end up either using booleans as a starter, or I do these corners by hand entirely. But there must be a more elegant solution. Do you guys have any tips how to tackle this?
  • FrankPolygon
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    FrankPolygon quad damage
    @martianlion It should be possible to create this geometry automatically with a bevel / chamfer modifier. Depending on the application's tool set: the width of the round over can be controlled by weights, groups or base geometry. Check the application's documentation to see what options are available in the latest version.

    Here's an example where the size of the round over is controlled by edge weights. The edge weight along the top of the mesh decreases towards the back of the shape which results in a tapered profile.


    Here's an example where the size of the round over is controlled by the underlying geometry. The relative size of the adjacent surface area is used to determine how large or small the round overs should be. Adjusting the position of the existing support loops around the outer edges will change the size of the round overs.



    Another option would be to create a very coarse cage mesh and use basic subdivision to round over the edges. What method makes the most sense depend on how accurate the curves need to be and what tools are available.
  • martianlion
    @FrankPolygon Thank you, you're the best. Using the initial geometry to determine all these shapes at once instead of doing bevels first, and then trying to connect them is... Welp. Great idea, and so simple too. Thanks again.
  • Tosyk
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    Tosyk polycounter lvl 9
    can you guys tell me how to do it smooth?
    outer shape is fine though

  • sacboi
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    sacboi quad damage
    Search back a few pages, there are a few options kindly shared that discuss various methods too resolve topology issues by using existing geometry to support mesh cage transform functions once subdiv is applied.    
  • Tosyk
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    Tosyk polycounter lvl 9
    @sacboi
    thanks, but that's what I need help with - to fix the topology.
    I looked through several pages back and didn't find solution unfortunately
  • Tosyk
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    Tosyk polycounter lvl 9
    @FrankPolygon
    thank you for you detailed and most structured explanation sir! this was not only helpful but also interesting reading.

    The reason I came here is because I faced difficulties which I can't solve myself. I should say that I'm always patiently looking for a solution before I start to ask anything. It seems my eye got blurred after few days of attempts. Also I have this so far and I'm pretty satisfied with the result:




  • lammer_228
    Hi guys, I have never modeled such shapes and I have a problem and the question is if I modeled the shape correctly and if the mesh is normal, you can see that I have a problem with setting up the smoothing groups at the seam, can anyone know how to achieve good shading and nice mesh?

    One of the problem

  • FeatherCritter
    Hello! I'm having trouble coming up with a decent solution for a deep, narrow cut into a smooth spaceship model. 







    + .obj : http://www.sashamorrissey.com/artwork/ShipHelpPleaseThankYou.obj

    I found this tip which was wonderfully useful for the outer corners of this very pointy mesh - I was wondering if there might be such a magic key to what is essentially the inverse of that shape.

    https://i.pinimg.com/originals/7d/ca/72/7dca726528b9c887de8a458631f8cbc3.png

    This is for a game so I think we can only have one level of subdivision. Naturally, this is right on top of the spaceship and highly visible. Any ideas how I can get this a little cleaner would be very, very appreciated! Thank you!
  • NodrawNT
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    NodrawNT polycounter lvl 6
    Hi, it's been a while since I've posted here !
    I've started a new project and I'm struggling with what could seem a very basic shape. I'm trying to model a cupola.
    Here's my reference :

    And here's what I'm struggling with : 

    I feel like the intersection isn't as rounded as it should be but yet I can't find how to manage it, also the top part is a mystery to me ...
  • sacboi
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    sacboi quad damage
    The shape is called a Pendentive, an elegant architectural solution most notably seen in the Church of Hagia Sophia, construction.

    And yes, fairly simple too model:

    • Subdivided cube
    • Spherify (quadify)
    • Boolean (cylindrical subtraction) 
    • Mirror
    • Cleanup - apply Chamfer/Bevel
    • Subdivide


    EDIT:
    This ever evolving subd thread really is a gold standard resource, imo without parity interweb wide :)
  • NodrawNT
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    NodrawNT polycounter lvl 6
    sacboi said:
    The shape is called a Pendentive, an elegant architectural solution most notably seen in the Church of Hagia Sophia, construction.

    And yes, fairly simple too model:

    • Subdivided cube
    • Spherify (quadify)
    • Boolean (cylindrical subtraction) 
    • Mirror
    • Cleanup - apply Chamfer/Bevel
    • Subdivide


    EDIT:
    This ever evolving subd thread really is a gold standard resource, imo without parity [email protected] e :)
     @sacboi thanks it will help me so much ! I didn't know about this church thanks ! Also, how did you manage to find it in all these pages ?
  • sacboi
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    sacboi quad damage
    Well, aside from attempting to archive/pdf info people had shared here just for my own reference :p but also I find simply googling a specific modeling issue will often return a match to this particular thread.
  • ronigeva
    Hi everyone
    I'm trying to model a leg of a Lego figure.
    There are 2 drills there, one of which is on a curved surface, and the other on a flat surface.
    A dril in the curved surface has details like bumps and other surfaces.
    I got problem in the bevel part
    i try to keep the topology clean and Quad.
    Can someone help me?

  • ConvexSurface
    Hello everyone, done some looking around and haven't found anything similar. I'm working from an old engineering drawing and looking for advice on how best to construct this shape:
    This was my attempt using in Blender primarily by bridging the two parts and then quite a bit of manual pulling and pushing of vertices to approach the described shape.

    The result seems to match the drawing in terms of shape, though there is a nasty crease where the transition meets the protruding tab and the construction method is kinda clunky.


    Would really appreciate any advice in terms of topology and construction methods. OBJ of the starting mesh attached for anyone who wants to give it a wack. Thanks in advance.
  • Jackskullcrack
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    Jackskullcrack polycounter lvl 2
    ronigeva said:
    Hi everyone
    I'm trying to model a leg of a Lego figure.
    There are 2 drills there, one of which is on a curved surface, and the other on a flat surface.
    A dril in the curved surface has details like bumps and other surfaces.
    I got problem in the bevel part
    i try to keep the topology clean and Quad.
    Can someone help me?


  • ronigeva
  • ronigeva
    Hi
    Can someone help me?
    i trying to connect 2 cylinders that have different number of edges
    and i cant change that number because it will affect the entire model
    how do i connect it?
  • .Wiki
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    .Wiki polycounter lvl 7
    Just collapse edges as they go to the center. Place some n-gons in the flat part of the side.
  • ronigeva
    The intention was to keep quads Without triangles or n-gons
  • wirrexx
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    wirrexx interpolator
    ronigeva said:
    The intention was to keep quads Without triangles or n-gons

    And why is that? it's a flat surface..


  • Scriptorium
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    Scriptorium polycounter lvl 3
    Hey!

    How in the world do I model a rectangular(-ish) hole on a curved mesh without these shading artifacts/lumps?

    My attempts with and without a flow around the hole both produce terrible shading, I also tried redistributing density but to no avail, I think there's something wrong with the flow.


  • sacboi
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    sacboi quad damage
    You're almost there!

    Establishing supporting geometry (uniformly spaced poly strips/edge loops) too control in this instance what appears to be a cut/hole topology upon a reflective surface possibly a 'vehicle'?!

    Is what I'd normally do when utising a similar workflow. Although not necessarily by hand, hence the overall uneven vertex positioning I see here, now if indeed the case I'd suggest a typical fix to smooth that curved region via the Shrinkwrap modifier:


    (Essentially, duplicate mesh as a parent, prior to those edited cuts)

    or

    Another option shared a few posts above yours - https://polycount.com/discussion/comment/2739935/#Comment_2739935
  • Scriptorium
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    Scriptorium polycounter lvl 3
    @sacboi Thanks for you help and the video you linked! 

    I actually had several problems, most of which from the lack of understanding of the fact that I'm trying to do something on a surface that follows not one, but several curves. So the solution was to patch the hole, relax the topology, dissolve useless edges (that did not contribute to the desired curvature), and then achieve the desired curvature using curve interpolation (in this case it was MiraTool's Curve Stretch). 
    I probably should've made a duplicate to shrinkwrap to later, but I ended up just cutting the hole and Extrude -> Shrinking it. 

    The result still looks a bit freehand but I'm fine with it in this case. The 5 edge polygon on the convergence of the plates is intentional as I feel it helped the shading (and I think this is the use case of the 5 edge polygon method mentioned in Pixar modeling docs, but correct me if I'm making a horrible mistake.



    So, my key takeaways for this would be:
    1. Make sure you are aware of the curves of the surface you're trying to work with
    2. Cut holes in the surface after you finish modeling the surface itself
    3. Have less messy sculpts? 

    Am I still missing something obvious?

    EDIT: Forgot to mention I actual decided to go with a bit of a different shape for the hole itself, but nothing that would've altered the way I tried to resolve this, this was simply an artistic choice at the moment.
  • sacboi
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    sacboi quad damage
    Nice solution, plus in my opinion it also depends upon prior planning in order to mitigate unforeseen problems.
    So, my key takeaways for this would be:
    1. Make sure you are aware of the curves of the surface you're trying to work with
    2. Cut holes in the surface after you finish modeling the surface itself
    3. Have less messy sculpts? 

    Am I still missing something obvious?
    Yes, I'd agree with your thoughts and no at the moment, nothing obvious comes too mind.
  • 99499
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    99499 node
    I'm afraid to make a new thread about this because the last one did not go well, but does anyone have any resources for learning about "combining" 2 different objects with different vert counts? For example, I'm about to make a pair of shoes for my character who is low poly, but the shoes area an important part of the design and will be a higher poly. Not sure if I should just leave them as separate objects and parent them or what the common workflow for this is. 
  • LoneRanger
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    LoneRanger polycounter lvl 2
    Hi, I'm creating game-ready model and I've got big problem with one part of it when trying convert to high poly for normal map baking.

    This is my low poly model with sharp edges marked:


    This is how it looks after applying Bevel (weight method) with 3 segments and then Subdivision surface modifiers:


    I've tried a lot of things - adding some support edges, various bevel options, cuts, etc. and nothing works. Only by marking sharp edge like on this image below, I can solve this one intersection, but then the other one is more broken.


    I don't know how to solve it. Even if I would like to start this model from scratch I can't imagine doing it in another way. 
  • FrankPolygon
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    FrankPolygon quad damage
    @LoneRanger Some of the smoothing artifacts may be the result of using an uneven number of bevel segments on areas where multiple surface angles converge. Try using the following bevel settings and see if that improves the smoothing behavior: 2 segments, 1.0 Shape, Arc Miter Outer.

    Increasing the mesh density tends to increase overall shape accuracy but subdivision modeling is something of an approximate process so there's almost always going to be some level of minor shape inaccuracy. Depending on various factors (player view distance, object size, texture density, etc.) minor smoothing artifacts on small parts may be a complete non-issue. Using the minimum amount of geometry to accurately hold the shapes balances shape accuracy with edibility.

    There's two common strategies for laying out the cage mesh topology on this type of shape transition: placing new support loop geometry over the existing edge segments that define the shapes or using the existing shape geometry as support loops and routing new support loop geometry between the existing edge segments.

    Working off the existing topology grid can be a quick and easy way to block out shapes and define sharper shape transitions but it also tends to create visible smoothing artifacts on the curved surfaces of low density cage meshes. Below is an example of what this process and topology can look like.



    Using existing geometry as support and placing new geometry between the edge segments that make up the curved surfaces can help reduce smoothing issues around shape transitions and tends to require less geometry but may produce slightly softer corners. Below is an example of what this process and topology can look like.



    Both of the previous examples start with a base mesh and most of the support loops are added with a bevel / chamfer operation. Adding additional shapes to the block out and adjusting the support loops is a relatively straightforward process. Loop select and dissolve edge operations are a quick way to clean up any excess geometry. Below is a comparison of some variations on the previously mentioned topology layouts.



    There's a few different ways to model this shape but here's an example that's fairly straightforward, easy to model and should be compatible with adding support loops via non-destructive modifiers.


    To recap:
    Determine whether or not minor smoothing artifacts will be visible to players before investing a significant amount of time in improving the results. Working off the existing geometry can be quick and easy but tends to create smoothing artifacts on low density meshes. Using the existing geometry as support and placing additional geometry between the existing edges of curved surfaces can help reduce smoothing issues around shape transitions.
  • ronigeva
    What can I do to avoid this pinch corners?

    i have "clean" topology and all the model is QUADS

  • FrankPolygon
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    FrankPolygon quad damage
    @ronigeva Looks like the intersecting geometry falls directly on top of the cylinder wall edge segments and this is causing deformation when subdivision is applied. Placing intersecting geometry between the existing cylinder wall segments will allow the existing geometry to act as support (which provides room for additional geometry) and will also help preserve the concentricity of the inner cylinder wall.

    With enough geometry it is possible to place intersecting geometry directly in line with cylinder wall segments but it's more efficient to use the existing cylinder wall geometry as support and just match the segment count so the intersecting geometry resolves as all quads. Here's an example that shows the basic topology.


    Support loops can be added once the basic topology is established. How sharp the edges need to be will depend on the object but any difference in edge width can be taken up in the support loop that runs around the base of the intersecting geometry where it meets the cylinder wall geometry. Below is an example of what this could look like.



    Subdivision modeling tends to be an approximate process so there's almost always going to be minor shape imperfections. Increasing the mesh density tends to increase the shape accuracy but tends to decrease editability and efficiency. It's important to look at the size of the object and average view distance as minor smoothing artifacts may not be visible. What's acceptable will depend on how the model will be used so it's important to balance accuracy with efficiency.

    Below is a comparison of wide and tight support loops on the rest of the shape. It's possible to maintain relatively sharp edges with minimal geometry so use the appropriate amount of geometry to support the shapes. Often it's a case of close enough is good enough.


  • Blaizer
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    Blaizer greentooth
    This method is achieved extruding the faces in the tube, and applying simple bevels. It's similar to what you have @ronigeva

    Using chamfers on the edges produces better results. But artifacts won't dissappear at all, because this kind of meshes needs more geometry. If you use pentagons, the mesh has less tension or shading artifacts.




    On the other hand, the top view is good enough, but it's better to use more geo for better results.

  • Rolf
    Good morning every one.After long time i am return in maya for continue modeling my ship,main reason why i stop its lumpenes in my model.How i must to fix this problem (screen below).how to smooth out these lumpenes.if i use nurbs modeling technique this problem disappears,but there are areas that cannot be created using nurbs modeling.
  • LoneRanger
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    LoneRanger polycounter lvl 2
    I'm starting to more and more understanding working with Subdiv but I encountered a problem with simple object. From the distance those artifacts will not be visible, but I really like to know how to solve intersections like this.
    This is my model with hard edges marked for bevel (I've tried method without it, just placing manual support loops but I got the same problems).


    This is what is happening:


    But when I connect those corners with hard edge below, corners then are looking fine, but my smooth shape is broken:


    I've tried placing loops in many places, also just around this problematic corners on second screenshot, but then there is a soft bump/stretch going on this circural smooth side face. 
  • wirrexx
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    wirrexx interpolator
    I'm starting to more and more understanding working with Subdiv but I encountered a problem with simple object. From the distance those artifacts will not be visible, but I really like to know how to solve intersections like this.
    This is my model with hard edges marked for bevel (I've tried method without it, just placing manual support loops but I got the same problems).


    This is what is happening:


    But when I connect those corners with hard edge below, corners then are looking fine, but my smooth shape is broken:


    I've tried placing loops in many places, also just around this problematic corners on second screenshot, but then there is a soft bump/stretch going on this circural smooth side face. 

    you do not have enough geo to support that extrude/intrude.


    And this was done with a 32 sided cylinder. The same method applied.
  • iacdxb
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    iacdxb polycounter lvl 3
    Hi,

    Any idea how to make three triangles to quad....? Thanks.


  • wirrexx
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    wirrexx interpolator
    iacdxb said:
    Hi,

    Any idea how to make three triangles to quad....? Thanks.




  • iacdxb
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    iacdxb polycounter lvl 3
    Thanks Wirrexx, I don't think I can do cut in middle bottom. see this...! Thanks.


  • wirrexx
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    wirrexx interpolator
    iacdxb said:
    Thanks Wirrexx, I don't think I can do cut in middle bottom. see this...! Thanks.



    ah another solution. It's not fully quaded, but two of your 3 tris are fixed.



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