Any two points, A and B, define a line, and a square can be constructed whose top edge is on that line.
Let C be the midpoint between A and B, and D be the corner of the square farthest from A.
The circle with center at C, through D, intersects the line AB in two places; let E be the
intersection furthest from A. Let F be the corner of the square furthest from B; the
rectangle with corners F, A, and E is a golden rectangle.

Please look at the source code of this page for more information.

Please look at the source code of this page for more information.