Hi Dave - Thanks! I managed to figure out the "secret sauce" today. I have spent hours looking through the Wiki article on Metapost. What it left out was the "u:newname" syntax. It either is not there or it is so hidden that I never found it. Martin's note from last night was helpful. I saw your definition for the boss formation and thought about using it. However, the standard this map must conform to calls for it to be represented as a triangle base with a bar across the top, almost like a table. The thfill line I came up with is ... thfill (0.2u,-0.4u)--(0.1u,0.2u)--(0.3u,0.2u)--(0.3u,0.4u)--(-0.3u,0.4u)--(-0.3u,0.2u)--(-0.1u,0.2u)--(-0.2u,-0.4u)-- cycle; Bill Gee On Monday, February 03, 2014 16:44:11 Dave Clucas wrote:

Have a look at this. http://therion.speleo.sk/wiki/doku.php/metapost

You will find a symbol which I defined for a stalagmite boss which I guess is what you are talking about.

def p_u_boss (expr pos,theta,sc,al)= T:=identity aligned al rotated theta scaled sc shifted pos; pickup PenD; p := (0.08u,0.25u)..(0,0.29u)..(-0.08u,0.25u); q := (0.16u,0.5u)..(0u,0.58u)..(-0.16u,0.5u); for i=0 upto 9: thdraw p rotated 36i; thdraw q rotated 36i; endfor p := fullcircle scaled 0.15u; thdraw p; enddef; To use a user defined symbol click on type U in the points drop down and then after the U, type in a colon followed by the name of your symbol so, in the case of the above "U:boss"

Dave Clucas daveclucas.com mycaves.org. daveclucas@icloud.com