Meshmagick Hydrostatic Issue

[battuta]

C:\Users\User\Geometry>meshmagick H1.stl -hs

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meshmagick - version 3.0
Copyright 2014-2021, Ecole Centrale de Nantes / D-ICE Engineering
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H1.stl successfully loaded
>>>> Performing hydrostatic computation on the current hull configuration considered at equilibrium
Traceback (most recent call last):
  File "C:\Users\User\anaconda3\Scripts\meshmagick-script.py", line 33, in <module>
    sys.exit(load_entry_point('meshmagick', 'console_scripts', 'meshmagick')())
  File "c:\program files\meshmagick3\meshmagick_cli.py", line 1196, in main
    raise RuntimeError("zcog should at least be given for correct stiffness values computations")
RuntimeError: zcog should at least be given for correct stiffness values computations

[battuta]

Center of gravity must be manually identified in order to calculate hydrostatics of STL files
meshmagick H1.stl --cog 0 0 0 -hs

[frongere]

This error message says that you must provide either zcog or the full cog coordinates for hydrostatics computations (this is new behaviour as before, not providing at least zcog were possible but resulted in non-correct stiffness matrix coefficients for roll and pitch).

Note that there is a difference between
meshmagick H1.stl --cog 0 0 0 -hs
and
meshmagick H1.stl --zcog 0 -hs

The first assumes you want a full 3DOF hydrostatic equilibrium to be performed while the second assumes that you only want a displacement equilibrium solution. In the latter case, not providing a displacement target will assume that the initial position of the hull gives the target displacement.