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IKO_gp_Ax3

# IKO_gp_Ax3 Interface

Describes a coordinate system in 3D space. Unlike a gp_Ax2 coordinate system, a gp_Ax3 can be right-handed ("direct sense") or left-handed ("indirect sense"). A coordinate system is defined by: its origin (also referred to as its "Location point"), and three orthogonal unit vectors, termed the "X
Direction", the "Y Direction" and the "Direction" (also referred to as the "main Direction"). The "Direction" of the coordinate system is called its "main Direction" because whenever this unit vector is modified, the "X Direction" and the "Y Direction" are recomputed. However, when we modify either the "X
Direction" or the "Y Direction", "Direction" is not modified. "Direction" is also the "Z Direction". The "main Direction" is always parallel to the cross product of its "X Direction" and "Y Direction". If the coordinate system is right-handed, it satisfies the equation: "main Direction" = "X Direction" ^ "Y Direction" and if it is left-handed, it satisfies the equation: "main Direction" = -"X Direction" ^ "Y Direction" A coordinate system is used: to describe geometric entities, in particular to position them. The local coordinate system of a geometric entity serves the same purpose as the STEP function "axis placement three axes", or to define geometric transformations. Note: We refer to the "X Axis", "Y Axis" and "Z Axis", respectively, as the axes having: the origin of the coordinate system as their origin, and the unit vectors "X Direction", "Y Direction" and "main Direction", respectively, as their unit vectors. The "Z Axis" is also the "main Axis". gp_Ax2 is used to define a coordinate system that must be always right-handed.

ReverseAxis
Direct

HRESULT ReverseAxis(int axis)

Parameters

axis -[in] 0-based index of an axis

Remarks:

Reverses direction of the axis

HRESULT Direct(VARIANT_BOOL* res)

res - [out,retval] - Returned orientation of this

Returns True if the coordinate system is right-handed. i.e. XDirection().Crossed(YDirection()).Dot(Direction()) > 0