1 files changed, 35 insertions, 0 deletions
diff --git a/crawl-ref/source/dat/clua/lm_1way.lua b/crawl-ref/source/dat/clua/lm_1way.lua
new file mode 100644
index 0000000000..6ce1e6d722
--- /dev/null
+++ b/crawl-ref/source/dat/clua/lm_1way.lua
@@ -0,0 +1,35 @@
+------------------------------------------------------------------------------
+-- lm_1way.lua:
+-- One-way stair marker.
+------------------------------------------------------------------------------
+
+OneWayStair = { }
+OneWayStair.__index = OneWayStair
+
+function OneWayStair.new()
+  local ows = { }
+  setmetatable(ows, OneWayStair)
+  return ows
+end
+
+function OneWayStair:activate(marker)
+  local ev = dgn.dgn_event_type('player_climb')
+  dgn.register_listener(ev, marker, marker:pos())
+end
+
+function OneWayStair:event(marker, ev)
+  if ev:type() == dgn.dgn_event_type('player_climb') then
+    local x, y = ev:pos()
+    dgn.terrain_changed(x, y, 'floor', false)
+    dgn.remove_listener(marker, ev:pos())
+    dgn.remove_marker(marker)
+  end
+end
+
+function OneWayStair.read(marker, th)
+  return OneWayStair.new()
+end
+
+function one_way_stair()
+  return OneWayStair.new()
+end