game.models.half-edge: additional vertex-diagonals word

diff --git a/extra/game/models/half-edge/half-edge-tests.factor b/extra/game/models/half-edge/half-edge-tests.factor
index 5431fcb07755c5c21f6e748d35ee99bab10eb7b9..cbfe514d7ebf253f9321e420dd615e7aab907097 100644 (file)
--- a/extra/game/models/half-edge/half-edge-tests.factor
+++ b/extra/game/models/half-edge/half-edge-tests.factor
@@ -62,5 +62,8 @@ connect-cube-edges
 [ { 1 4 2 } ]
 [ cube-edges first vertex-neighbors ] unit-test
 
+[ { 3 5 6 } ]
+[ cube-edges first vertex-diagonals ] unit-test
+
 [ { 1 4 3 5 } ]
 [ cube-edges first face-neighbors ] unit-test

diff --git a/extra/game/models/half-edge/half-edge.factor b/extra/game/models/half-edge/half-edge.factor
index 1b799bb4b371c62a1d044092038a5d52a0f2d6fe..eeb3e6116f1f6d6c660ddb6a773055d82c182fff 100644 (file)
--- a/extra/game/models/half-edge/half-edge.factor
+++ b/extra/game/models/half-edge/half-edge.factor
@@ -37,6 +37,9 @@ TUPLE: edge < identity-tuple face vertex opposite-edge next-edge ;
 : vertex-neighbors ( edge -- edges )
     [ opposite-edge>> vertex>> ] [ each-vertex-edge ] (collect) ;
 
+: vertex-diagonals ( edge -- edges )
+    [ next-edge>> opposite-edge>> vertex>> ] [ each-vertex-edge ] (collect) ;
+
 : vertex-valence ( edge -- count )
     [ each-vertex-edge ] (count) ;