LDCad - How do I manage groups?

[Roland Melkert]

Different question, but since it fits the thread topic…

I'm wondering if this is a bug or if I'm using groups wrong: Let's say I create a group in a submodel, so that subfile is the "top" level for that group. Then I switch to the main model session and go into nested mode. I select the group that's in the submodel, and add some parts from the main model to it. Everything works fine, I can select and manipulate* the group with all of its parts.

But now let's say I've closed LDCad, and I go back to the model another day. Then, selecting the group in nested mode only affects those parts in the submodel—the parts added to it from the main model aren't selected, even though they're still in the group according to the file code. In other words, when LDCad is closed and re-opened, it seems to "forget" any group parts that are not in its top-level subfile.

I finally manged to 'observe' this behavior, it turns out this is not supposed to be allowed. Higher groups can contain ones from submodels, it shudn't be possible to add parts from an higher model to a group living in a submodel. I will be blocking such additions in Alpha 2.

Well, not totally fine…the group center shows up in very odd places if I select parts from the non-top-level of the group, and transforming the group leads to unexpected results with these parts…but that's another story![/i]

This is actually the same problem, the steering axle group sits in a lower submodel then the hub and wheel.

LDCad should have prevented making such a group in the first place.

The reason is all operations on groups are done in the group's owner world space. The axle is at Z 40 inside the steering model but at -400 on the higher level, so the wheel and hub will receive the higher to lower space corrections while not needing it.

To solve this you should make a new group at the chassis level out of the steering group, hub and wheel.

If it is hard to select things, you can always use the hide feature (or navigate to a lower step where everything is still visible)

I will add extra checks to the "add selection to group" operation, firing a warning if not all is actually added.