Synopsis:
\linethickness{dim}
Declares the thickness of subsequent horizontal and vertical lines in a picture to be dim, which must be a positive length (see Lengths). It differs from \thinlines
and \thicklines
in that it does not affect the thickness of slanted lines, circles, or ovals.
© 2007–2018 Karl Berry
Public Domain Software
http://latexref.xyz/_005clinethickness.html