Click this link to see a parallelogram door.[br][url=https://www.evernote.com/l/AANpFOC6RvBOOIzq2m7KkHz761XwygLIgLk]https://www.evernote.com/l/AANpFOC6RvBOOIzq2m7KkHz761XwygLIgLk[/url] [br][br]In the following applet, the green door is rectangular. Notice the movement of D when you open the door by dragging D. [br][br]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.[br][br]Can the door be tilted to the left in the real building?

Here is an example of open parallelogram window.[br][url=https://www.evernote.com/l/AANmPC4awV9Pl44Z03MD5cwgZyb2zYCK3v4]https://www.evernote.com/l/AANmPC4awV9Pl44Z03MD5cwgZyb2zYCK3v4[/url]