Segment

An alternative interpretation of paths that is convenient for mathematical operations.

Here, a path is viewed as a list of segments with a start and end point.

= LineSegment Coordinate Coordinate

| Quadratic Coordinate Coordinate Coordinate

| Cubic Coordinate Coordinate Coordinate Coordinate

| Arc

{ start : Coordinate

, end : Coordinate

, radii : ( Float, Float )

, xAxisRotate : Float

, arcFlag : ArcFlag

, direction : Direction

}

The four types of segments.

For segments, the xAxisRotate field is in radians.

fromPath : Path -> List Segment

Create segments from a path

toPath : List Segment -> Path

Convert a list of segments to a path

It is assumed that for every two adjacent segments in the list, the first segment's end point is the second segment's starting point

Operations

at : Float -> Segment -> ( Float, Float )

Get the location at a point on the curve, only defined in the range [0, 1].

length : Segment -> Float

The approximate length of a segment

{ minDepth : Int

, error : Float

}

-> Segment

-> Float

Supply the options for the approximation

minDepth: Minimum recursion depth for calculating the length of arc segments. Default is 10.
error: Minimal amount of progress that an recursive step must make. Default is 1.0e-12.