Selecting objects beyond clipping plane



I am having an issue when i am trying to move objects relative to my current cplane. I will clip out the rest of the model and only wish to move the objects shown but somehow objects that are in the background and are clipped off will be selected and will move when the desired objects are moved.

How the desired objects are selected is after the clipping planes are turned on to clip out the undesired part of the model, the cplane is set face of the “wall”. Then, view:top in order to get a straight on view of the work area. A Control-Shift window selection is drawn around the desired objects to move, when additional “control points” appear to be selected when moving the objects, I unlock and rotate the view to find objects that are clipped out being selected in my window selection.
This is troubling because it could cause other parts of my model to be changed without me noticing when steps were taken to try to ensure that only the desired area would be edited.

Please help, is this a bug? or is there a way to prevent this from happening.

(Pascal Golay) #2

Hi Scott - if you select from the visible side of a clipping plane that is active in that view, then stuff behind the clipping plane should not be selected - but the clipping plane must be enabled for that view - by default it is enabled only in the viewport where it is created, Enable and disable in the clipping plane Properties.

Any better?



That’s exactly the “bug” I’m addressing here. When selecting from the visible side, objects in the hidden side of the model are somehow selected. This is in the model tab and not through any layout viewport.

(Pascal Golay) #4

Hi Scott - but, in the view in which you are selecting, is the clipping plane active? If so, can you please send an example model here or to




Yes, the clipping plane is active and the items are hidden until i notice that the control points of objects behind the active clipping plane are moving along with the desired selected items. I only notice it when i select from a straight on view and not from a rotated view.

(Pascal Golay) #6

Hmm - I cannot repeat this here - I make two surfaces, one in front and one behind the clipping plane that is active in Top only . I window select in Top, and only get the visible objects selected and not the clipped one nor the points for that if they are on. I can only select these in other views where the clipping plane is not active.



I would like to get you the model i am working with but it is a really large file and i doubt it would go through email but i dont want it shared on a public forum either. It has happened to me once before in a different model but a similar scenario selecting objects beyond an active clipping plane. I couldnt figure out why objects that should have lined up were altered on the opposite side of the model until i caught it doing it once. As will all “errors”, replicating the problem can often be difficult or impossible.

(Pascal Golay) #8

Hi Scott- can you export the incorrectly selected objects behind, a few objects in front, and the clipping plane to a new file, confirm the behavior is repeatable in that file, and then send is that? is private. Or, you can SaveSmall. zip and upload the big file to

My guess of the moment is that maybe very large model extents are messing with the depth testing - I don’t know if clipping planes are susceptible to that, but it seems at least possible.



email and exported model sent to i was able to recreate the situation in the exported model.

(Pascal Golay) #10

Hi Scott - thanks, I added



Im not aware of what that is. I cannot follow the link as it asks me to login.

(Pascal Golay) #12

Hi Scott - yep, sorry - that is set to public view now. It has been fixed, but I have not got a build that has the fix in yet to test it.