Avoiding artifacts when importing from 3D Studio

  • Hi guys,
    hoping you can help. I've created a simple model in 3DS Max. I was advised to avoid boolean operations, but there are some things that are all-but impossible using simple primitive/box modelling, and I'm not a good enough modeller to create what I want with patch modelling.
    Anyway, as you can see below, I have a simple shape - a cylinder with a chamfered wedge removed to create a depression for a switch. The object is clean in 3DS Max, but when I export to OBJ extra geometry is created that creates visible artifacts.
    I tried exporting to 3ds, and whilst it fixes this issue, it creates 5 more due to the lack of export options.
    I've tried turning OFF 3D Studio's optimisation options, but other than that I'm at a loss for how to avoid this problem as it is the result of a process that happens during conversion, not whilst modelling.

    I've tried exporting using triangles instead of quads, but it makes no difference.

    Any thoughts about solutions would be appreciated.


  • @matb I bet this is one of those un-welded polys things that @vilters always talks about.

  • Poser Ambassadors

    For that, I would have to see the obj file myself because from the screengrabs I see many differences between Max and Poser version.
    Welding can be an issue as could ngons, and Poser does not like long thin triangles..

  • @vilters Is there a way I can send you the original 3DS max file for you to take a look at please?

  • Poser Ambassadors

    Hi Mathb => You can send the files (Max and the obj) to tony.vilters@telenet.be

    I don't have Max, but can check the files in Blender and Poser to see what's going on.
    Best regards, Tony

    PS = include your import settings if applicable.

  • The tris are being created somewhere either in export or import because it's splitting the n-gons. That one long poly at the top of the curve has at least 6 vertices along that edge. Some import/export functions try to get rid of those by turning them into tris

  • Poser Ambassadors

    Boolean operations are fast but do have a reputation for creating scrappy topology which can cause problems when moving between apps. I think you may have to spend some time cleaning up the mesh in Max before exporting.

    I haven't used Max but a quick search has some suggestions like converting the result of booleans to an Editable Mesh or Editable Poly for tidy up & checking geometry; using high poly count when converting to Editable followed by Optimise to reduce poly count; using dense meshes prior to running a boolean operation etc.

  • Thank you everybody for your comments and observations, and especially thanks to Vilters for taking a look at my mangled model. It was mangled as a result of a bad loft, compounded by using booleans and not manually breaking up some ngons into tris or quads, and the cherry on top was 3D Studio's far from perfect OBJ export.

    The solution was to create a cleaner loft, tidy up some of the vertices, and create the cutaway manually rather than using booleans. This definitely doesn't produces as elegant a result in 3DS but it DOES export cleanly to Obj and then into Poser as you can see.

    Once again, thank you all for taking the trouble to share your advice.