parallelogram door
Click this link to see a parallelogram door.
https://www.evernote.com/l/AANpFOC6RvBOOIzq2m7KkHz761XwygLIgLk
In the following applet, the green door is rectangular. Notice the movement of D when you open the door by dragging D.
Drag B to the right of the vertical white line to make the door a parallelogram. Imagine movement of D again and try opening the door.
Can the door be tilted to the left in the real building?
Here is an example of open parallelogram window.
https://www.evernote.com/l/AANmPC4awV9Pl44Z03MD5cwgZyb2zYCK3v4