Distribution is to several objects distribute in the workplace as considering regular. Eg: there are 6 rectangles in the workplace, when click distribute, follow dialog window will pop-up:
left: Distribute left and right based on the left line.
center: Distribute left and right based on the middle line.
space: Distribute left and right based on distance between two objects.
right: Distribute left and right based on the right line.
top: Distribute up and down based on the top line.
center: Distribute up and down based on the middle line.
space: Distribute up and down based on distance between two objects.
bottom: Distribute up and down based on the bottom line.
