regular
peripheries
orientation shape = polygon, the following attributes are also used: sides (default = 4)
skew (default = 0)
distortion (default = 0) shape=point is only affected by peripheries
width
height fixedsize
fontname
fontsize
height
label
style
width label and image (if so specified) plus the value of the margin attribute. The values of the width and height attribute specify the minimum size. See also fixedsize (if fixedsize=shape, the size of the node equals width and height).