X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=blobdiff_plain;ds=sidebyside;f=mgraph.h;h=06c53e214ec1f5cac09a151f827b8caaf7344b77;hb=fcb05a81ecead2dcd3375c6d4ceb528ca6e181c0;hp=4ab020585b8e57609cbff0808aedbc2f1dc54d27;hpb=5723c8ee37d7790cb788ef5469e5f231d81391de;p=moebius2.git

diff --git a/mgraph.h b/mgraph.h
index 4ab0205..06c53e2 100644
--- a/mgraph.h
+++ b/mgraph.h
@@ -125,9 +125,7 @@ int edge_reverse(int v1, int e);
   for ((vy)=0; (vy)<Y; (vy)+=Y-1)				\
     for ((vx)=0; (v)= (vy)<<YSHIFT | (vx), (vx)<X; (vx)++)
 
-#define VERTICES_SPAN_JOIN_P(v0,v1)		\
-  /* v0 and v1 must be (nearly) adjacent */	\
-  (!!((v0) ^ (v1) ^ (1<<(XBITS-1))))
+int vertices_span_join_p(int v0, int v1);
 
 typedef double Vertices[N][D3];
 struct Vertices { Vertices a; };