Shift+green flag.. The r, g, and b sliders are for whatever colour you want. This is meant to be a demonstration but I added in opacity anyway. The two circles represent x1 and y1 and x2 and y2 respectively. If you press generate with no rotation two of the rectangle's corners will be placed at the points. Rotate it, and, well, you should know what happens. Press 1 to set the x and y of one circle, and 2 for another.
Uses trig. For thumbnails. How on earth would I do polygons? Gosh I need to think of doing that. I made the cellophane sprinkler inside(it's what I used to create the thumbnail effect), go check it out. 21/06(or 07 idk)/2017-shared and added option for much faster generation with rotation=0 28/07/16 Fixed an overlooked error in drawing rectangles with rotation 0. 13/02/18 Fixed an embarrassingly blatant issue that made the project uninteractable. Whoops...