You can color the perimeter of a box by specifying a color value in the box statement. For example:

 

red box (xsize of TwinBox)(ysize of TwinBox)

 

draws the perimeter of the box in red.

 

If solid is specified, ESL fills the box with the requested color or with the default color, if none is specified. For example, the statement:

 

solid red box (xsize of TwinBox)(ysize of TwinBox)

 

draws a box and fills it with red.