segseg

Segment-segment intersection classifier and calculator for Elixir

Monthly Downloads: 10,054

Programming language: Elixir

License: MIT License

Tags: Geolocation    

README

Segment-Segment Intersection for Elixir

Calculates intersection type and location for two line segments.

Installation

defp deps do
  [{:seg_seg, "~> 0.1.0"}]
end

Usage

Full Documentation

The SegSeg module provides a function intersection that calculates the intersection between two line segments and returns a tuple with three elements:

1. Boolean true if the two segments intersect at all, false if they are disjoint
2. An atom representing the classification of the intersection:
   • :interior - the segments intersect at a point that is interior to both
   • :vertex - the segments intersect at an endpoint of one or both segments
   • :edge - the segments are parallel, collinear, and overlap for some non-zero length
   • :disjoint - no intersection exists between the two segments
3. A tuple {x, y} representing the point of intersection if the intersection is classified as :interior or :vertex, otherwise nil.

Examples

SegSeg.intersection({2, -3}, {4, -1}, {2, -1}, {4, -3}) #=> {true, :interior, {3.0, -2.0}}
SegSeg.intersection({-1, 3}, {2, 4}, {-1, 4}, {-1, 5}) #=> {false, :disjoint, nil}
SegSeg.intersection({1, 2}, {3, 0}, {2, 1}, {4, 2}) #=> {true, :vertex, {2, 1}}
SegSeg.intersection({-1, 0}, {0, 2}, {1, 4}, {-1, 0}) #=> {true, :edge, nil}

Tests

> mix test