Yeah so the bar is broken. As far as i can see it dosent affect gameplay as it resets when you go edit your organism ( not the cell)
There are a couple of issues that might be related:
opened 02:05PM - 22 Feb 23 UTC
intermediate
programming
bug
C#
stage:microbe
It looks like rigidity slider does a divide by zero to end up with ridiculously … wrong numbers when it tries to move when there's exactly 0 MP left. This can be triggered with a very specific MP cost multiplier to be able to place parts to reach 0 MP and then trying to move the rigidity slider.
https://community.revolutionarygamesstudio.com/t/membrane-rigidity-visual-bug/6059
Video: https://youtu.be/9c4ekW5QNI8
opened 06:03AM - 26 Sep 22 UTC
intermediate
programming
bug
C#
stage:microbe
End result:

So looks like some kind of really low negative number for rigidity comes from somewhere in that case.
It's probably enough to have a call to `Clamp` in the rigidity change callback, but would be nice to know why this happens to evaluate whether other bars in the game are potentially also impacted.
Could you tell step by step what you did before the bug? Did you have modified game settings?
Yep, those issues are the most relevant open issues. Though neither of them is exactly as the issue described, as the issue can happen when the cost per step is too low, for example due to low mutation cost and being in multicellular. There is a fix to that issue by switching to a floating point (instead of a whole number) for the remaining MP, @KasterisK has worked a bit on this, but the changes did not end up being completed:
Revolutionary-Games:master
← Revolutionary-Games:convert_mp_to_float
opened 04:00PM - 23 Feb 23 UTC
**Brief Description of What This PR Does**
As discussed in #4150. MP is round… ed to 3 fractional digits in the GUI elements.
Of course needs further testing.
**Related Issues**
Fixes #4150.
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members reviewing this PR)
- [ ] Initial code review passed (this and further items should not be checked by the PR author)
- [ ] Functionality is confirmed working by another person (see above checklist link)
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Hopefully that gets finished at some point as people keep running into this issue.