+ if {$i < $last} {
+ # This line has an arrow at the lower end: check if the arrow is
+ # on a diagonal segment, and if so, work around the Tk 8.4
+ # refusal to draw arrows on diagonal lines.
+ set x0 [lindex $coords 0]
+ set x1 [lindex $coords 2]
+ if {$x0 != $x1} {
+ set y0 [lindex $coords 1]
+ set y1 [lindex $coords 3]
+ if {$y0 - $y1 <= 2 * $linespc && $x1 == [lindex $coords 4]} {
+ # we have a nearby vertical segment, just trim off the diag bit
+ set coords [lrange $coords 2 end]
+ } else {
+ set slope [expr {($x0 - $x1) / ($y0 - $y1)}]
+ set xi [expr {$x0 - $slope * $linespc / 2}]
+ set yi [expr {$y0 - $linespc / 2}]
+ set coords [lreplace $coords 0 1 $xi $y0 $xi $yi]
+ }
+ }
+ }