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too many unknowns in a sinlge group (by Markus)
Hi, I designed a 2d-sketch in which every constraint is solved - checked after every single step. Adding a new line the message "too many unknowns in a sinlge group" comes up. I don't understand the new line is the only "unknown"/undefined with only two contraints to set to solve DOF.

I don't see the possibility to split it in several groups because it is one single and closed 2D-construction. So my question: Is there a limitation of constraints and if so is it possible to expand the number of limints. There are only few steps to finalize. Computation shouldn't be a problem, my computer is not at limit.

Thank you for your support and for feedback
Markus
Sat Dec 18 2021, 10:11:04
(no subject) (by Paul)
There is a hard limit on the number of free parameters in a sketch. IIRC it is around 1024. Each point in a 2d sketch adds 2 parameters (x and y coordinates).

It is planned to remove that limit along with some solver improvements but that hasn't happened yet.

You might try making one sketch with all construction lines and define major dimensions. Then make a second group with mostly the real entities constrained to the previous ones. Not sure if that will reduce it enough for you.
Sat Dec 18 2021, 17:20:58
too many unknowns in a sinlge group (by Markus)
Thank you for your support. I've tried but unfortunatelly it doesn't work for me, too many DOFs now I'm not and I don't want to start from scratch again.

Unfortunatelly I'm not a developer to solve the limit problem.

So little bit frustrated but great program anyway - much faster and much more productive than freecad, what a pitty that it's limited this way.

Thanks
Markus
Mon Dec 20 2021, 06:01:10
(no subject) (by ruevs)
Yes there is a hard limit of 1024 "unknowns" per sketch in SolveSpace - it is a performance consideration. See here https://github.com/solvespace/solvespace/issues/386

The restriction is here https://github.com/solvespace/...1f56cb16/src/solvespace.h#L213 if you can compile from source - following the instructions on GitHub you can increase this value.

But it will be slow https://github.com/solvespace/...ues/386#issuecomment-998587512

Usually if you hit this limit it means that you are doing something "wrong" - usually too munch copy-paste. The example in the above issue is typical.

If that is your case, usually there are better ways (apart from the advice Paul gave you above) "New Group | Step Translating" and "New Group | Step Rotating" will help. This issue https://github.com/solvespace/solvespace/issues/841 contains a practical example where they helped.
Tue Dec 21 2021, 05:30:57
(no subject) (by Paul)
@Markus, We have just merged significant changes to the constraint solver and I doubled the MAX_UNKNOWNS. Hopefully these changes will appear here very soon:

https://github.com/solvespace/solvespace#via-automated-edge-builds

If you're building from source, be careful to start fresh and follow the directions, as there is a new dependency on Eigen.
Fri Dec 31 2021, 15:22:03
thank you so much (by Markus)
This saves a lot of my work and makes many things much easier and faster.

In the meantime I tried Freecad-sketcher but solvespace is so much better.

Thanks
Markus
Sun Jan 9 2022, 03:37:09
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