% illustration of the command patch
figure
x1 = [0 1 1]; y1 = [0 0 1]; z1 = [0 0 0];
% x1, y1, and z1 are the corners of a triangle
patch(x1,y1,z1,'r');
hold on
x2 = [0 1 0]; y2 = [0 1 1]; z2 = [0 0 1];
% x2, y2, z2 defines another patch
patch(x2,y2,z2,'g');
view(3) % to show in 3d
grid on