Get rid of unused faces in an object ?

Is there a way to get rid of unused faces in Hexagon ?
If one combines two objects to one mesh (weld the two meshes) there are often faces from one mesh wich will be trapped in the volume of the second mesh.
Of course it's possible to delete all those trapped faces manually or go through a  set of bolean operations to make sure that each mesh is exactley cut at the boundaries of the other,
But even with this workflow the "inner" faces at the cutting sides have to be deleted by manually selection before the meshes are welded at the contact line.

So my question: is there a shorter way to get rid of all unused (trapped) faces in an object ?

Thanks in advace

Comments

  • Wee Dangerous JohnWee Dangerous John Posts: 1,605
    edited January 2023

    It can be done, or should I say there are work arounds. But it depends on the shapes you are trying to join together, and if bits where they meet have the same number of points.

    Any chance you could do a screen grab of the objects ?

    Things which may help are the Hide Selected Faces option (bottom right of screen) and the Bridge tool, but it hard to advise you without seeing the project. 

    Post edited by Wee Dangerous John on
  • One idea is to apply a dark surface material to all visible, leaving all the hidden faces with no surface. Save Project. Then select all the unassigned surfaces and delete them. Incre-save Project if it works without crashing.

     

  • atoxicatoxic Posts: 142

    At the moment I am working on a type of SF/Steampunk console. In an early stage I combined the rectangular body of the console table with the ciruclar disk which will become a kind of radar screen. (See A, B). If the disk is positioned at the console table there are some hidden faces which are completly enclosed by the mesh of the console table (see C and D),
    If the two parts are welded into on object those hidden faces are conserved. Besides that I find it unelegant to have faces without a function, those hidden faces may cause a mess on later stages of modelling or in renders. 
    If one duplictes the table and the disc, peforms a bolean operation on the table with the disk (E) and afterwards on the disk with the table (F) there is a clean contact line where both meshes can be welded. But again there a some faces whicht are trapped inside the mesh (see E). 

    Till now I know no good alternative to delete those unused faces (in E) manually (best prior to welding the meshes, so you get G) or correct the positions of the contact points and delete the trapped faces (in D)..Because I know that some modelling programs allow to get rid of trapped / hidden faces after welding of two meshes, I am curious wheter I missed this function in Hexagon or if this is really missing.

     

    hx console work 1.png
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    hx console work 2.png
    1241 x 790 - 321K
  • Yes, hidden faces are not desirable -- will increase render times plus make the model that much heavier for no reason.

    No Boolean. Shoot it over to D/S and you'll see why.

    No, you did not miss a function to remove trapped/hidden faces, doesn't exist AFAIK.

    Looks like a fun console. If there is any way you can get a circle loop from the base to draw up the disk part, that would eliminate trying to match seams together after a merger. {and wouldn't need a merger}

     

  • atoxicatoxic Posts: 142

    Alright. I couldn't get rid of the trapped faces in the figure. So I used my old approach and modelled glass and screen of the console as separate meshes.
    At the moment his is a kind of beta status, only a static prop, till now no moving parts or animation. But it fits well in some (retro) SF scenes.

    HX Console sp1.png
    959 x 598 - 902K
  • Catherine3678abCatherine3678ab Posts: 8,352

    atoxic said:

    Alright. I couldn't get rid of the trapped faces in the figure. So I used my old approach and modelled glass and screen of the console as separate meshes.
    At the moment his is a kind of beta status, only a static prop, till now no moving parts or animation. But it fits well in some (retro) SF scenes.

    Coming along nicely.

    Some ideas:

    If one has transparency toggled on, then one can select mesh "through" mesh.

    One can squish some mesh together so it's not visible where you don't want it.

    How to make moving parts - can depend upon which program you plan to use next and also how you plan to rig them. If I recall correctly, the levers for examples, could be separate meshes [export out one by one] then grouped together on the scene tab in D/S. Some dials on the Parameters tab can be renamed if desired. Save each piece as a prop, THEN, select the root and save as a scene subset.

    And a nifty big tip for making a bunch of pieces in Hexagon into 'one' mesh without loosing the uvmaps, is to rename all the pieces that are to be 'one' exactly the same. Select all those items and export out an .obj. In another session of Hexagon, import in that new .obj - it should be all the pieces now together as one group. If all went well, can then import said .obj into the working project and carry on. {for eg. to have all the bases for the levers glued to import/export as one with the console}

     

  • FirstBastionFirstBastion Posts: 7,765

    generally it is quick and easy to manually remove unseen faces from the model. Removed faces often help with the UV unwrapping as well.

  • Catherine3678abCatherine3678ab Posts: 8,352

    True however also with Hexagon the act of removing faces can cause crashes, so incre save project often ;-)

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