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Best way to reduce size/number of polygons on an STP model?

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    Best way to reduce size/number of polygons on an STP model?

    Hi... not Unreal Studio specific (unless there is a way to do this in Unreal)... I get highly detailed STP files from our factory, and I need a way to dramatically reduce the size of these files even at cost of detail... Anyone have a pipeline suggestion for how to go about this? Trying to import the STP models into Unreal has proven rather difficult. They're so large that I think it's crashing unreal every time.

    open static mesh in editor and reduce triangulate by percentage until your mesh is maintain in look
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      There are two factors at play: the number of polygons in the meshes, and the overall number of meshes.

      Unreal has a pretty good mesh reduction process that UE4 Archviz mentioned, but that only helps once they've already been imported. I also think it maintains the original mesh in order to be non-destructive which is great and helps with performance, but not necessarily with file size (which can itself be important for mobile device deployment, not typically a problem for desktops). This also doesn't help reduce the overall number of meshes.

      Depending on the detail of the model and what you need to actually see in Unreal, you might be able to save on both triangles and meshes by getting rid of things like nuts/bolts/washers or other similar small details that aren't needed for the overall result you are trying to achieve. If possible, it would be best to do this when exporting the stp file. If not, the dataprep features that come with Unreal Studio can be used to help. For example:

      If they don't need to move, it can also help to join meshes together. Again, probably best to do it outside of unreal if possible, but can be done in Unreal by merging actors.

      (I feel like I remember seeing another example where they were using dataprep to automatically remove small objects, but can't find that link immediately...)

      There are also third-party options that provide solutions for this kind of thing. Optim and InstaLOD come to mind, although I'm sure there are others. If this is a process that you are going to have to do repeatedly, it's definitely worth looking into.


        cwm83 This is exactly the help I need. Absolutely on the right track. I will indeed have to do this repeatedly and unfortunately for me,
        1 - I don't have access to the models in solidworks prior to when they're sent to me... nor do I have my own copy of solidworks to edit the models ...
        2 - the factory sending me these models is presumably so inundated with work that getting them to strip out the nuts and bolts for me seems to be a "big ask."

        For the most part, the models can absolutely be joined together and I won't need them to articulate... only on some rare occasions... and even then I'm sure if I could just reduce these Goliaths down as much as possible to where I can get them to open - then I could take them into blender or something and re-detach the meshes where needed to animate articulations later. I'm so new to all of this (with respect to STP files, and the unreal engine) that the tips you've given regarding dataprep / Optim / InstaLOD are somewhat lost on me... but I get the sense that it's the right place to start. I'll do some searching around and read the docs at the link your provided to see if I can decipher further. Really appreciate that help. Cheers!


          Some cheap and good standalone LOD creation software are Atangeo Balancer and Mootools Polygon Cruncher.


            Another potential solution is to use a different 3d modeling software that you are familiar with to open the stp file and then merge/reduce meshes there, and then export to an fbx. I tend to use either Rhino or 3dsMax, but stp is common enough that I think most software should be able to open it. You will likely lose the meta data that comes with the stp file, but I'm not sure unreal brings that in anyways.

            Finally, it's so much easier to test workflows on a small model first. You should get a sample file with just a tiny portion of the overall model, one that you can import into Unreal without problems, and then use that model as a base to test different triangle and draw call reduction strategies.


              DarkS474 - Thank you - I will look into those.

              @CSM83 - So the software that I'm comfortable with is Modo... however, I'm embarrassed to say how old the version I'm working with is. Company won't buy a new license. Opening STPs in my version of Modo doesn't appear to be possible unfortunately. I totally agree with respect to the starting with a smaller model to test things out w/ respect to workflow... again though, unfortunately, getting our factory to send us anything is tough as it is. What I may do is try to find a smaller, free STP model somewhere online and experiment with that.

              Again, thanks for your help everyone.


                cwm83 ** sorry.