defobj tricirpair
 abs p_c 200 200 0
 part p pt_circ c
 extend p_a e_a ang 270 -radius_circ
 extend p_b e_b ang 270 radius_circ
enddef

define(`circle',`
abs circcircl$1x$2 $1 $2 90
extend circcircl$1x$2 circcircll$1x$2 ang 359 radius_circ
')