Boolean subtract not working as expected

[skyeg321]

I have two terrain objects that I created using a plug-in called mega-fiers terrain which basically gets information from Google Earth and creates objects for you. I have two of these objects one covers a larger area and has less detail in terms of polygons, also the material that is applied to it has less resolution. I want to nest the smaller, higher resolution terrain inside the larger one by creating a Boolean with the small terrain slightly above the larger. I would then move the smaller train to exactly in line with the other. I hope the screenshots help explain what I am doing.

I've converted both objects to editable polys and I've tried a lot of the options within the Boolean dialog box, none of which seemed to do what I want. Am I doing something obvious wrong? I can make a video showing the problem if needed.

Thanks for your help!

[PROH · Accepted solution]

Hi. Understand what you're trying to do, but can't really see from neither your description nor your pictures what's going wrong. So here's some advise that maybe (or maybe not) will help you.

1) Boolean operations will only work "correct" if the objects are watertight enclosed objects. So make sure the objects are enclosed and that all vertices are welded.

2) Boolean operations in Max has never worked specifically well. They'll often mess up the mesh and UVW and leave you with a serious job cleaning up.

3) In your specific case, the small piece of terrain has straight edges, and it looks like it fits nicely within the polygons of the larger terrain. Therefore I would choose to manually cut out (if nessesery), select and delete the polygons in the large terrain, making place for the smaller piece of terrain. This way you can preserve the UVW in both terrains.

Hope it helps

[skyeg321]

 what I ended up doing was converting both editable polys than performing a Boolean which would cut the polygons but not actually remove the material,  then I would just delete the polygons that I  did not want.  Thanks for your help!