Knowing two points of a rectangle, how can I figure out the other two?

Question

Hey there guys, I\'m learning processing.js, and I\'ve come across a mathematical problem, which I can\'t seem to solve with my limited geometry and trigonometry knowledge o

Answer 1

Calculate the angle of the line joining the two midpoints using an arc-tangent function applied to the vector you get between them.

Subtract 90 degrees from that angle to get the direction of the top edge

Starting from the top-center point, move relative (1/2 top width x sin(angle), 1/2 top width x cos(angle)) - that gets the top right corner point.

Continue around the rectangle using the sin and cos of the angles and widths as appropriate

As a test: Check you made it back to the starting point