Initializes a #graphene_euler_t using the angles and order of another #graphene_euler_t.
If the #graphene_euler_t src is null, this function is equivalent to calling graphene.euler.Euler.init_ with all angles set to 0.
a #graphene_euler_t
the initialized #graphene_euler_t
Initializes a #graphene_euler_t using the angles and order of another #graphene_euler_t.
If the #graphene_euler_t src is null, this function is equivalent to calling graphene.euler.Euler.init_ with all angles set to 0.