Limitations of BReps

[Mr. Bodo Hasubek 3]

Hi,

 

I am trying to (ab?)use BReps to create a ship hull model with real plate thickness (not just the outer surfaces), since they import nicely into RHino3D.

All plates are created as a closed Breps using a self-written feature that basically takes an outer hull plate and makes a 3D plate-BRep from it with a given plate thickness. Then I try to union as much from them together as possible, since they provide really nice joining lines when they work.

However, I keep on running into trouble when I try to make a union from several such plates.

For one thing, it  appears to depend on the order in which the plates are added to the union.

Another problem is shon in the picture:

On the left side, keeping the "correct" order and only using "simple" plates I could union all the plates as shown. As soon as I try to union the additional plate shown in yellow in the right picture, the whole BRep display disappears. To give some hints, where the problem may come from, I would like to point out, that the new plate has a "nasty" shape and connects to several plates.

 

Any ideas where the limitations of BReps lie and how to circumvent them?

 

Thanks,

Bodo

[Mr. Bodo Hasubek 3]

I take the part that the Breps export nicely to Rhino3D back: Only the original surfaces get exported, not the true intersections which is kind of pointless then...