Separating Polygons

 From:  Michael Gibson
926.3 In reply to 926.1 
Hi Pozero - to make separate polygons you will first need to create different surfaces for each part.

Some parts may naturally be modeled as different surfaces that are then booleaned together, but if you have one larger surface that you want to export as separate polygons you may need to draw a curve and use the Edit/Trim function to split the surface into smaller pieces.

For 2 pieces that touch along a common edge, you should generally make sure that they are joined together (use Edit/Join if necessary, or this is also built in to when you use booleans) so that when converted to polygons the polygons will match along the common edge.

Then to enable breaking apart into separate polygons, when you save to a mesh, expand the Meshing options dialog by clicking on the little arrow in the bottom left corner, and un-check "Weld vertices along edges".

When that option is checked, MoI will produce a mesh that has one single set of shared vertices along a common edge.

When that option is unchecked, the polygons for each surface will have their own vertices along the common edge, making it easier to separate the polygon out into different chunks in your polygon modeling program. Usually there will be some option in your polygon program to separate out different pieces or to select only all polygons directly connected to each other, those are the kind of options that you can use to break it into separate pieces when you have exported an unwelded mesh.

- Michael