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4 Geometry standards
tangent
The operation "tangent" shall return the tangent vector along this generic curve
(class GM _ GenericCurve) at the passed parameter value. This vector approximates
the derivative of the parameterization of the curve. The tangent shall be a unit vector
(have length 1.0).
length
The operation "length" returns the distance between the two points along the
curve.
sampiePoint
The operation "samplePoint" returns an ordered point array (class
GM_PointArray) that lie on the curve segment. In most cases, these will be related to
control points used in the construction ofthe segment.
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Fig. 4.42. Operation samplePoint
asGM_LineSegment
The operation asGM _ LineSegment decomposes a line string into an equivalent
sequence of line segments.
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Fig. 4.43. Operation asGM _ LineSegment
asGM_Geodesic
The operation "asGM _ Geodesic" decomposes a geodesic string into an equivalent
sequence of geodesic segments.