add note about correct behavior

index.html

@@ -63,6 +63,10 @@
             world.setBlock('minecraft:diamond_block', 3, -1, 0); // east
             world.setBlock('minecraft:iron_block', -3, -1, 0); // west
 
+            // NOTE the trapdoor should open AWAY from the diamond block
+            //  the repeaters should face "inward"
+            //  the pistons should face "outward"
+
             // world.setBlock('minecraft:glass', 1, 0, 0);
             // world.setBlock('minecraft:glass', 0, 0, 1);
             world.setBlock('minecraft:coal_block', 0, -1, 0);
@@ -126,4 +130,4 @@
     testPipeline();
 </script>
 </body>
-</html>
+</html>