% feta-sleur.mf 
mode_setup;
thin:=.2pt;
thick:=5thin;
ybow:=.2;
abow:=1.5;

def draw_slur(expr a,b,d) =
	beginchar(0,0,0,0) "Embedded mf";
		% huh, factor 8?
		z1=8a;
		z2=8b;
		save alpha; alpha=angle(z2-z1);
		save len; len=length(z2-z1);
		z3=(0,0);
		z4=(len/2,len*ybow*d);
		z5=(len,0);
	 	save beta; beta=abow*angle(z4-z3);
		penpos3(thin,90+beta);
		penpos4(thick,90);
		penpos5(thin,90-beta);
		pickup pencircle;
		path boogje;
		boogje = z3l{dir(beta)}..z4l{right}..z5l{dir(-beta)}
			..z5r{dir(180-beta)}..z4r{left}
			..z3r{dir(180+beta)}..cycle;
		penlabels(1,2,3,4,5);
		boogje := boogje rotated alpha;
		% silly mo*tex convenction
%		boogje := boogje shifted ((x1-x2)/2,0);
		fill boogje;
		endchar;
	enddef;

def sign(expr a) =
	((abs(a))/(a))
	enddef;

def xdraw_slur(expr a,b,d) =
	beginchar(0,0,0,0) "Embedded mf";
		% huh, factor 8?
		z1=8a;
		z3=8b;
		save alpha; alpha=angle(z3-z1);
		z2=(1/2[x1,x3],1/2[y1,y3])+d*ybow*(x3-x1)*dir(alpha+90);
	 	save beta; beta=d*sign(y3-y1)*abow*angle(z2-z1)-alpha;
%		message "d: "&decimal d;
%		message "dy: "& decimal sign(y3-y1);
%		message "alpha: "&decimal alpha;
%		message "beta: "&decimal beta;
		penpos1(thin,alpha+beta+90);
		penpos2(thick,alpha+90);
		penpos3(thin,alpha-beta+90);
		pickup pencircle;
		fill z1l{dir(alpha+beta)}..z2l{dir(alpha)}
			..z3l{dir(alpha-beta)}..z3r{dir(180+alpha-beta)}
			..z2r{dir(180+alpha)}..z1r{dir(180+alpha+beta)}
			..cycle;
		penlabels(1,2,3);
		endchar;
	enddef;