Hey guys,
just wanted to let you know, that I've cracked the case in the meantime.
Here are my findings:
def convert_matrix_left_to_right(m): # http://www.techart3d.com/2016/02/convert-left-handed-to-right-handed-coordinates/ # m = op.GetMg() new_m = c4d.Matrix( m.off, m.v1*-1, m.v2, m.v3) return new_m def rotate_y_axis_180(): # Construct your own matrix based on rotation of axis # https://www.mathworks.com/help/phased/ref/roty.html x = c4d.Vector(-1, 0, 0) y = c4d.Vector(0, 1, 0) z = c4d.Vector(0, 0, -1) off = c4d.Vector(0, 0, 0) return c4d.Matrix(off, x, y, z) def GetGlobalRotation(obj): m = obj.GetMg() new_m = rotate_y_axis_180() * convert_matrix_left_to_right(m) return c4d.utils.MatrixToHPB(new_m, order=c4d.ROTATIONORDER_XYZGLOBAL)Indeed you have to convert from a left-handed (c4d) (hpb) to a right-handed (houdini) (xyz) coordinate system... plus I've found that you need to add 180° to the y axis, so I constructed a matrix in rotate_y_axis_180 that I can multiply to my converted matrix.
Hope it helps someone...
Thank you guys for your input! Have a great weekend and stay safe!
Cheers,
Lasse