I am modeling my helmet that I originally inquired about how to approach in the other thread that I started. Thanks for all the tips.

I have the basic shape laid out by modifying a sphere via control points. I am able to cut in half (for mirroring) and doing some other detail type work. The control -points remain available for the sphere (helmet shape) the whole time. obviously I can hide or unhide these at will. However, at some time during the model process, the control points are no longer appearing. turning these on or off does nothing.

Is this a bug or am I missing something? I have been turning control points on and off during this process and now they are gone.

Any info and/or help appreciated. Thanks.

Hi slayer - at some point you got a boolean or a join in there.

When you have 2 joined surfaces that are joined at a trim edge that is not a "natural" edge of the underlying surfaces, then control points are not able to be turned on for that object. That is to prevent the problem of pulling apart a gap in what is supposed to be a shared joined edge.

You can use Edit/Separate to break such objects into individual surfaces, and then control points should always be available for an individual surface.

Check out here for some more detailed information with some illustrations:
http://moi3d.com/wiki/FAQ#Q:_Why_does_show_points_work_for_some_objects_but_not_others.3F

- Michael

Makes perfect sense. Thank you.