Mirror modifier and hair disconnect/reconnect not working together
Open, Needs TriagePublic


System Information
Linux (Arch), GTX 1080

Blender Version
2.79b f4dc9f9d68b

Short description of error

When using a hair particle system on an object with a mirror modifier, and trying to disconnect and then reconnect the hair the particle positions are messed up.

Exact steps for others to reproduce the error

  • create a cube object
  • add a mirror modifier with merge and clipping options enabled (it seems to happen in the same way with separated mirrored cubes also, though)
  • add a hair particle system to the object

  • comb hair in particle edit mode

  • disconnect and reconnect particle system

  • enable 'Simple' children in particle system settings and disable them again

More Info

  • After the steps done for the first and second blend files everything looks good. Adding a particle system and particle edit on a mirror object seems to work.
  • But disconnecting and reconnecting has the (immediately to be seen) effect of moving all the hair from the 'mirrored' (right) part of the object to the rightmost end of the left part, as shown in the third blend file
  • Enabling and disabling children shows that in addition to that problem the particle system data seems to have been messed up further by the disconnect/reconnect, as after that last step the hair positions are completely messed up.