I need to display arrows alongside to line features. Lines represent water pipes. The issue I'm facing is that lines are a concatenation of numerous line features of various lengths. Therefore, symbols are attached to every line, whatever its length. This makes symbols either overlaying or touching eachother (as in example below).
Inside my mapfile, I define the display rules of my symbols in the
STYLE SYMBOL "wp_arrow" GAP -100 COLOR 255 0 0 OFFSET -5 -99 SIZE 6 END
I would like these rules to apply only to line features being more than 10 meters long (or x map units).