I have found a method here which seems to work well but any other less complicated ways would be appreciated!

viewtopic.php?t=424

Hi, I am a geologist tracing some geological maps with Inkscape. I am trying to trace a line which has black triangles pointing in a direction perpendicular to the line direction where the triangle is located and with one side encased in the line i.e. I can distinguish two sides of the triangle beca...