Segment Distance
The minimum distance between a point and a segment, or the minimum distance between points of two segments.
segm_distance(p1, p2, p3, p4 = c())
p1, p2 |
end points of the first segment. |
p3, p4 |
end points of the second segment, or the point |
If p4=c(), determines the orthogonal line to the segment through
the single point and computes the distance to the intersection point.
Otherwise, it computes the distances of all four end points to the other segment and takes the minimum of those.
Returns a list with component l the minimum distance and components
p, q the two nearest points.
If p4=c() then point p lies on the segment and q is
p4.
The interfaces of segm_intersect and segm_distance should be
brought into line.
## Not run:
plot(c(0, 1), c(0, 1), type = "n", asp=1,
xlab = "", ylab = "", main = "Segment Distances")
grid()
for (i in 1:20) {
s1 <- matrix(runif(4), 2, 2)
s2 <- matrix(runif(4), 2, 2)
lines(s1[, 1], s1[, 2], col = "red")
lines(s2[, 1], s2[, 2], col = "darkred")
S <- segm_distance(s1[1,], s1[2,], s2[1,], s2[2,])
S$d
points(c(S$p[1], S$q[1]), c(S$p[2], S$q[2]), pch=20, col="navy")
lines(c(S$p[1], S$q[1]), c(S$p[2], S$q[2]), col="gray")
}
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.