public subroutine intersects(x1, x2, x3, x4, y1, y2, y3, y4, s, t)

intersects

Calculate the intersection between two line segments.

Description

This subroutine calculates the intersection point of two line segments defined by their endpoints (x1, y1) to (x2, y2) and (x3, y3) to (x4, y4). If the segments intersect, the parameters s and t will contain the normalized distances along each segment to the intersection point. The intersection point can be calculated as: $$x = s \cdot (x2 - x1) + x1 y = s \cdot (y2 - y1) + y1$$ If the segments do not intersect, s and t will be outside the range [0, 1].

Examples

References

Arguments