<complexType name="ClothoidType">
<annotation>
<documentation>A clothoid, or Cornu's spiral, is plane
curve whose curvature is a fixed function of its length.
In suitably chosen co-ordinates it is given by Fresnel's
integrals.
x(t) = 0-integral-t cos(AT*T/2)dT
y(t) = 0-integral-t sin(AT*T/2)dT
This geometry is mainly used as a transition curve between
curves of type straight line to circular arc or circular arc
to circular arc. With this curve type it is possible to
achieve a C2-continous transition between the above mentioned
curve types. One formula for the Clothoid is A*A = R*t where
A is constant, R is the varying radius of curvature along the
the curve and t is the length along and given in the Fresnel
integrals.</documentation>
</annotation>
<complexContent>
<extension base="gml:AbstractCurveSegmentType">
<sequence>
<element name="refLocation">
<complexType>
<sequence>
<element ref="gml:AffinePlacement">
<annotation>
<documentation>The "refLocation" is an affine mapping
that places the curve defined by the Fresnel Integrals
into the co-ordinate reference system of this object.</documentation>
</annotation>
</element>
</sequence>
</complexType>
</element>
<element name="scaleFactor" type="decimal">
<annotation>
<documentation>The element gives the value for the
constant in the Fresnel's integrals.</documentation>
</annotation>
</element>
<element name="startParameter" type="double">
<annotation>
<documentation>The startParameter is the arc length
distance from the inflection point that will be the start
point for this curve segment. This shall be lower limit
used in the Fresnel integral and is the value of the
constructive parameter of this curve segment at its start
point. The startParameter can either be positive or
negative.
NOTE! If 0.0 (zero), lies between the startParameter and
the endParameter of the clothoid, then the curve goes
through the clothoid's inflection point, and the direction
of its radius of curvature, given by the second
derivative vector, changes sides with respect to the
tangent vector. The term length distance for the</documentation>
</annotation>
</element>
<element name="endParameter" type="double">
<annotation>
<documentation>The endParameter is the arc length
distance from the inflection point that will be the end
point for this curve segment. This shall be upper limit
used in the Fresnel integral and is the value of the
constructive parameter of this curve segment at its
start point. The startParameter can either be positive
or negative.</documentation>
</annotation>
</element>
</sequence>
</extension>
</complexContent>
</complexType>
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