API Reference > geometry-core > Curve > CurvePrimitive > getFractionToDistanceScale getFractionToDistanceScale Method If the curve primitive has distance-along-curve strictly proportional to curve fraction, return true If distance-along-the-curve is not proportional, return undefined. When defined, the scale factor is always the length of the curve. This scale factor is typically available for these curve types: All LineSegment3d Arc3d which is a true circular arc (axes perpendicular and of equal length). CurveChainWithDistanceIndex This scale factor is undefined for these curve types: Arc3d which is a true ellipse, i.e. unequal lengths of defining vectors or non-perpendicular defining vectors. bspline and bezier curves getFractionToDistanceScale(): undefined | number Returns - undefined | number scale factor or undefined Defined in curve/CurvePrimitive.ts Line 417 Last Updated: 11 June, 2024