Check if two polygons overlap: Difference between revisions

=={{header|Julia}}==

<syntaxhighlight lang="julia">using Plots

using Polyhedra

using GLPK

lib = DefaultLibrary{Float64}(GLPK.Optimizer)

const poly1 = polyhedron(vrep([

0 0

0 2

1 4

2 2

2 0

]), lib)

const poly2 = polyhedron(vrep([

4 0

4 2

5 4

6 2

6 0

]), lib)

const poly3 = polyhedron(vrep([

1 0

1 2

5 4

9 2

9 0

]), lib)

println("Polygons poly1 and poly2 intersect at ", npoints(intersect(poly1, poly2)), " points.")

println("Polygons poly1 and poly3 intersect at ", npoints(intersect(poly1, poly3)), " points.")

println("Polygons poly2 and poly3 intersect at ", npoints(intersect(poly2, poly3)), " points.")

const P1 = polyhedron(vrep([

-1.9 -1.7

-1.8 0.5

1.7 0.7

1.9 -0.3

0.9 -1.1

]), lib)

const P2 = polyhedron(vrep([

-2.5 -1.1

-0.8 0.8

0.1 0.9

1.8 -1.2

1.3 0.1

]), lib)

Pint = intersect(P1, P2)

println("Polygons P1 and P2 intersect at ", npoints(Pint), " points.")

plot(P1, color="blue", alpha=0.2) #!jl

plot!(P2, color="red", alpha=0.2) #!jl

plot!(Pint, color="yellow", alpha=0.6) #!jl

</syntaxhighlight>{{out}}

<pre>

Polygons poly1 and poly2 intersect at 0 points.

Polygons poly1 and poly3 intersect at 5 points.

Polygons poly2 and poly3 intersect at 5 points.

Polygons P1 and P2 intersect at 8 points.

</pre>

[[File:Poly intersect.svg|thumb|center]]