SOLVESPACE -- parametric 2d/3d CAD
Examples
Tutorials
Features
Download
Reference
Technology
Library
Forum
Contact
USER FORUM

(you are viewing a thread; or go back to list of threads)

Vertical symmetry constraint prevents horizontal constraint (by Murray)
Hi Jonathan

I have a box within a box with a vertical symmetry constraint. The inner box is free to drag horizontally but the solver prevents me putting any horizontal constraint to position it. What am I doing wrong? Example attached.

BTW brilliant software, thank you.

Murray
Fri Mar 21 2014, 00:32:35, download attachment hconstraint.slvs
(no subject) (by Jonathan Westhues)
Thanks. In your sketch, the left edge of the hole is constrained both vertical and symmetric about the x axis. That's redundant, so SolveSpace should report an error; it's a bug that it doesn't immediately. (SolveSpace treats both inconsistent and redundant constraints as errors; see the tutorial for details.) Confusingly, it reports that error only after you've added the additional constraint.

To fix the problem, delete the unnecessary "vertical" constraint. Let me know if you still have trouble.
Fri Mar 21 2014, 02:28:56
(no subject) (by Murray)
OK, I understand.

The V constraint comes automatically when making the box - makes sense, most boxes will be orientated that way.

I note that you can fix the solve by deleting the V constraint on either the inner or outer boxes which still must leave the other over constrained. I guess thats part of the bug you allude to above.

Thanks
Murray
Tue Mar 25 2014, 02:30:49
(no subject) (by Jonathan Westhues)
As a special case, if you select a line segment that's already constrained horizontal/vertical, and constrain it horizontally/vertically symmetric, then SolveSpace deletes the redundant constraint. That works only if you select the line segment though, and not if you select its two endpoints; I suspect that's how you ended up with your confusing sketch.
Tue Mar 25 2014, 06:19:41
Post a reply to this comment:
Your Name:
Your Email:
Subject:
(no HTML tags; use plain text, and hit Enter for a line break)
Attached file (if you want, 5 MB max):
© 2008-2018 SolveSpace contributors. Most recent update Nov 22 2018.