Houdini Script
$YMIN
on translate node Y translate field.
put the object on the 0 ground.
Houdini Attribute Wrangle
Normal Vector Rotation
Rot value 3.14 is 360 degree of rotation as radian.
Houdini Normal, Left Right Veter creation vex
on attribute wrangle
vector up_vector = {0, 1, 0};
@N = cross(@N, up_vector);