normal2
function normal2(ps: number[][], t: number): number[]
Defined in local-properties-at-t/normal/double/normal2.ts:23
Returns a normal vector (not necessarily of unit length) of a bezier curve
at a specific given parameter value t by simply taking the tangent at
that point and rotating it by 90 degrees.
- uses double precision calculations internally
- unlike normal, if the tangent vanishes at
t(e.g. at a cusp or where control points coincide) a normal is still returned (based on the direction the curve leaves the point in; or arrives at the point in ift === 1); only if all control points coincide is[0,0]returned
Parameters:
| Name | Type | Description |
|---|---|---|
ps | number[][] | a linear, quadratic or cubic bezier curve given by its ordered control points, e.g. [[0,0],[1,1],[2,1],[2,0]] |
t | number | the parameter value where the normal should be evaluated |