Enhance documentation of `ts_bspline_elevate_degree'
@@ -2329,7 +2329,7 @@ ts_bspline_to_beziers(const tsBSpline *spline,
* instance.
*
* @param[in] spline
- * The spline to elevate.
+ * The spline to be elevated.
* @param[in] amount
* How often to elevate the degree of \p spline.
* @param[in] epsilon
@@ -2337,8 +2337,9 @@ ts_bspline_to_beziers(const tsBSpline *spline,
* a sequence of bezier curves (see ::ts_bspline_to_beziers). After degree
* elevation, the split points of the bezier curves are merged again. This
* parameter is used to distinguish between the split points of the
- * decomposition process and the wanted discontinuity points. A viable
- * default value is ::TS_POINT_EPSILON.
+ * decomposition process and discontinuity points that should be retained.
+ * A viable default value is ::TS_POINT_EPSILON. If negative, the resulting
+ * spline, \p elevated, forms a sequence of bezier curves.
* @param[out] elevated
* The elevated spline.
* @param[out] status
