polyand - Script command

Combines two polygons into one using the Boolean 'and' operation.

The polygon vertices are contained in a single matrix of dimension Nx2 (or 2xN), where N >= 3 is the number of vertices. The dimension 2 corresponds to the x,y positions. For example, a square of side length 1 can be described by V = [ 0,0; 1,0; 1,1; 0,1] or V = [ 0,1,1,0;0,0,1,1].

Example

In this example, we create two polygons and then show how the different Boolean operations can be done. We set up a mesh and use the inpoly function so that we can image the polygons and easily see the result.

# set up a mesh for imaging polygons with the inpoly command
x = linspace(-1,3,200);
y = linspace(-1,3,200);
X = meshgridx(x,y);
Y = meshgridy(x,y);
# enter 2 polygons and the polygon boolean operations
V1 = [ 0,0; 1,0; 1,1; 0,1];
V2 = [ 0,0; 2,2; 0,2];
V3 = polyand(V1,V2);
V4 = polyor(V1,V2);
V5 = polydiff(V1,V2);
V6 = polydiff(V2,V1);
V7 = polyxor(V2,V1);
# image all the polygons
image(x,y,inpoly(V1,X,Y),"x","y","V1");
image(x,y,inpoly(V2,X,Y),"x","y","V2");
image(x,y,inpoly(V3,X,Y),"x","y","V1 and V2");
image(x,y,inpoly(V4,X,Y),"x","y","V1 or V2");
image(x,y,inpoly(V5,X,Y),"x","y","V1 - V2");
image(x,y,inpoly(V6,X,Y),"x","y","V2 - V1");
image(x,y,inpoly(V7,X,Y),"x","y","V1 xor V2");

The results are shown in the following images

See Also

List of commands , polyor , polydiff , polyxor , polyarea , centroid , polyintersect , inpoly , polygrow , mesh order