convexPolygonOverlap {tigers}

Overlap of Two Convex Polygons

Description

Find the intersection of two convex polygons.

Usage

convexPolygonOverlap(A, B)

Arguments

A, B

two two-column matrices giving the coordinates of two polygons.

Details

The intersection of two overlapping convex polygons is a single convex polygon.

The two input polygons must be in clockwise order.

Value

a two-column numeric matrix giving the coordinates of the overlap between the two input polygons.

Author(s)

Emmanuel Paradis

See Also

is.clockwise, polygonOverlap

Examples

X <- matrix(rnorm(3800), ncol = 2)
A <- X[chull(X), ]
Y <- matrix(rnorm(3800), ncol = 2)
B <- Y[chull(Y), ]

plot(rbind(A, B), type = "n", asp = 1)
polygon(A)
COLS <- c("blue", "red")
text(A, labels = 1:nrow(A), font = 2, cex = 1.5, col = COLS[1])
polygon(B)
text(B, labels = 1:nrow(B), font = 2, cex = 1.5, col = COLS[2])
legend("topleft", , c("A", "B"), text.font = 2, text.col = COLS)
O <- convexPolygonOverlap(A, B)
polygon(O, border = NA, col = rgb(1, 1, 0, 0.5))