I'm trying to clip the upper part of a building generated with A2S that has a complex roof. Here's an image of simplified version illustrating the situation.
I tried adding a probollean on top and subtracting the roof but the result is very random : sometimes when updating the RC object within, everything breaks and the boolean results in a mess. Also if I add detail in the mesh, the boolean can take ages to perform and becomes hardly possible to adjust the RC object.
Is there another way to achieve this ? A workflow similar to clipping spline but with a surface would be cool.