On 2012-05-02 Alan BRASLAU
For example, in the minimal example below, how can one obtain a transparent arrow without getting an X-ray vision of the arrowhead?
Maybe I'm reinventing the wheel here, but you can write a small macro that only draws the lines you want. Here is an idea: \starttext \startMPpage linecap := squared; penscale := .5bp; pickup pencircle scaled penscale; def drawmyarrow expr p = _apth:=p; _myfinarr enddef; def _myfinarr text t = draw _apth cutafter point (-ahlength+.1penscale) on _apth t; fill arrowhead _apth t enddef; drawarrow origin -- (1cm,0) withtransparency(1,.5) ; drawarrow origin -- (0,1cm) withtransparency(1,.5) ; drawmyarrow (1.5cm,0) -- (2.5cm,0) withtransparency(1,.5) ; drawmyarrow (1.5cm,0) -- (1.5cm,1cm) withtransparency(1,.5) ; \stopMPpage \stoptext The (-ahlength+.1penscale) are of course empiric. You should find the correct formula to always have a nice match of line and arrow whatever ahlength and ahangle values are in use. Marco