Jump to content
Cinema 4D Plugins

ElectroOrca

Trying to split object into parts

Recommended Posts

ElectroOrca    0

Super new to Cinema 4D, so bear with me. :P

I'm working with a .stp file of a car part. From what I read, Cinema 4D doesn't open .stps, so I downloaded FreeCAD to convert the file. I converted it to a .obj. When I import it into C4D, however, the model is just one solid piece. In FreeCAD, I'm able to select and move around various sections of the model, basically take it apart. Why can I not do this in Cinema 4D? Am I exporting it wrong from FreeCAD or is there a Cinema4D setting I'm missing?

 

My terminology is probably off, but any help would be great.

 

Let me know anymore info that may be needed. 

 

Share this post


Link to post
Share on other sites

Cerbera    1,815

Hello and welcome to the cafe...

 

You're right, Cinema doesn't open stp files. If the program you are converting files in doesn't have a setting to preserve the polygon groups of the original, then you either have to find one that does, or you have to do it by hand in Cinema, which is easy enough.

 

In polygon mode, double clicking any part of the mesh will select it and all the polygons connected to it. Alternatively you can select connected parts by selecting one polygon and doing U,W 'Select Connected'. Then you just have to right-click, choose split from the contextual menu, which creates a new polygon object containing your selection, then you have to press delete to remove those polys from the original model. Rinse and repeat for the other parts.

 

CBR

Share this post


Link to post
Share on other sites
ElectroOrca    0
  • Topic Author
  • Thanks for the answer, Cerbera.

    Doing it by hand in Cinema 4D sounds a little daunting. FreeCad is showing that there are about 86 pieces. Does that mean I have to export each one separately in FreeCAD and put it back together in Cinema 4D?

     

    I'm guessing the whole "polygon mode" instructions are for when I actually have separated polygons to work with? Sorry, really new - still learning terminologies and settings.

     

    Worse comes to worse, can you recommend a program that can convert .stp and preserve the polygons?

    Share this post


    Link to post
    Share on other sites
    Cerbera    1,815
    2 hours ago, ElectroOrca said:

    Doing it by hand in Cinema 4D sounds a little daunting. FreeCad is showing that there are about 86 pieces. Does that mean I have to export each one separately in FreeCAD and put it back together in Cinema 4D?

    No that's not so daunting with only 86 pieces. It would be daunting if it was 10,000 ! And no, I meant bring it all into Cinema as one piece, and then split up when it gets there.

     

    2 hours ago, ElectroOrca said:

    I'm guessing the whole "polygon mode" instructions are for when I actually have separated polygons to work with?

    No. Polygon mode is simply the mode by which we can select single or groups of polys in Cinema, in order to split them off into separate objects, usually based on material groups you will be using in your render. Double clicking a polygon just makes life easier by allowing you to quickly select any polys that are already connected. So in the case of a racing car for example, where you want all the tyres to have the same material, then all the polys that make up the tyres need to be extracted to their own mesh via the SPLIT command. So, depending on how the original car was put together, you would begin by selecting a few polys on each tyre and doing U,W to 'select connected'. If the model has been built well, then only the polys comprising the tyres will be connected. If it hasn't been built well, or with that purpose in mind, then you may find that all polygons are connected, in which case this feature won't help you at all. If that is the case, you should use the other selection tools like Phong Break, Loop and and Fill Selection to manually set and define groups of polys you will split off into new objects.

     

    2 hours ago, ElectroOrca said:

    Worse comes to worse, can you recommend a program that can convert .stp and preserve the polygons?

    Alas no, I won't use any CAD software for my 3D work because I have yet to find any CAD program that produces decent clean topology. Usually there is a LOT of cleanup work involved in importing CAD meshes into cinema.

     

    CBR

    Share this post


    Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now

    • Recently Browsing   0 members

      No registered users viewing this page.

    ×