ConcaveSegment( x3 - r3, z3, r3, z3, z2);
ConcaveSegment( x3 - r4, z3, r4, z4, z3);
ConvexSegment( x5 + r5*cos(a6), z5 - r5*sin(a6), r5, z5, z4);
+ polygon([[x6, z6],
+ [x5, z5+0.01],
+ [0.01, z5],
+ [0.01, z6]]);
+
if(0)
intersection(){
union(){
translate([x5 + r5 * cos(a6), z5]) circle(r=r5);
- polygon([[x6,z6-1],
- [x5,z5],
- [1,z5],
- [1,z6-1]]);
difference(){
translate([-50,z4]) square([52,z2-z4]);
// circle(