fractionToPointAndDerivative Method

Return the point (x,y,z) and derivative on the curve at fractional position.

  • Note that the derivative is "derivative of xyz with respect to fraction".
  • The derivative shows the speed of the "fractional point" moving along the curve.
  • The derivative is not generally a unit vector. Use fractionToPointAndUnitTangent for a unit vector.

fractionToPointAndDerivative(fraction: number, result?: Ray3d): Ray3d

@returns a ray whose origin is the curve point and direction is the derivative with respect to the fraction.

Parameter Type Description
fraction number fractional position along the geometry.
result Ray3d optional receiver for the result.

Returns - Ray3d

a ray whose origin is the curve point and direction is the derivative with respect to the fraction.

Defined in

Last Updated: 28 October, 2024