I'm sorry I'm not sure if I understand you correctly. Could you make some sketch that illustrate what you would like to achieve please?
Artur,
Thanks,
I'd like to slice the curved wall along the plane of the red line.
Tony
Seems it is not my best day
Do you want to divide the panel into two parts (create two panels instead of one) along this line or just see the results along this line?
No, I just want to modify the panel geometry to cut off anything above that line
See the attached picture. The direction indicates which part to cut off (depends if you indicate top left or bottom right corner of the panel).
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