Hi all.
I am playing with the trial version of MoI (Michael, the new version is still valid after three days), and I have a question about booleans. The case is simple. I draw a rectangle, then extrude (a sort of "room"). Then I put a plane on one face, as a "door". Now, if I subtract the door from the room, I don't obtain a "hole". Instead, if I previously deleted the upper face of the room, the boolean operation with the door works as I expected. Maybe I am missing something fundamental about booleans operations in this situation?

Ciao

Antonino

Hi Antonino - yes I see that is a bit odd.

The problem here is that if you have a solid base object, the booleans will tend to expect either a solid cutting object, or for a surface one that fully divides the solid into 2 smaller solids.

In a sense the booleans will try to generate a solid as the result if the original object was a solid.

If you want to cut out a piece of a solid like you are showing there, you should use the Edit/Trim tool for that type of cut instead. Trim does not attempt to keep solids as solids and will let you cut up the outside skin of a solid any way you want.

It may be easier for you to use Edit/Separate on the solid to break it into 6 individual surfaces first, and then work on those surfaces separately. You can then later on use Edit/Join to glue them back together into a connected object after you are done editing the pieces.

Also instead of using a plane as the cutting object, I'd recommend using a rectangle curve as the cutter instead. Coincident surfaces tends to be a more difficult calculation and also it can be more difficult to select by clicking when there are 2 coincident surfaces. Curves are much easier to select, so it is more of a recommended workflow to use a curve as the cutting object in this case.

- Michael

???
No result is the same : roof or not roof :)
Select as on the image !
The door will made a hole :)

Thanks Michael,

you are really superfast in answering :-)
I understood your explanations, and I will make some more experiments with the different methods. I am quite a novice in NURBS modelling, but now that I found a tool so nice to use as MoI, I plan to learn and improve my skills.

Ciao

Antonino

Hi Pilou,

Sincerely I did not understand your message (and the figure). I tried several times, so I am quite sure to have selected the room as base object and the door as object to subtract. Could you please explain better your results?

Ciao

Antonino

in my example there no floor so that works :)