level_design.txt: document special marker props

Document the marker properties connected_exclude, veto_disintegrate,
veto_fragmentation, and veto_shatter, which can effect the dungeon cell
a marker is on is treated by the game.

1 files changed, 21 insertions, 0 deletions

diff --git a/crawl-ref/docs/develop/level_design.txt b/crawl-ref/docs/develop/level_design.txt
index ce574e7908..56e06d1715 100644
--- a/crawl-ref/docs/develop/level_design.txt
+++ b/crawl-ref/docs/develop/level_design.txt
@@ -1844,6 +1844,27 @@ It's very important that your finished level never croaks during
 level-generation. A Lua error at this stage is considered a validation
 failure.
 
+Special dungeon-related Lua marker properties
+---------------------------------------------
+
+There are several properties a Lua marker can have which will affect the
+dungeon cell which they are on:
+
+* connected_exclude: Consider the cell to be separate from neighboring
+      cells with identical or similar features.  Currently only useful
+      for preventing adjacent doors from grouping together into a gate,
+      forcing them to open and close as separate doors.  See the Evil
+      Zoo (minivault_9) in dat/mini.des for an example.
+
+* veto_disintegrate: If this property is set to "veto" then the cell
+      will be immune to disintegration.
+
+* veto_fragmentation: If this proprety is set to "veto" then the cell
+      will be unaffected by fragmentation (Lee's Rapid Deconstruction
+      spell).
+
+* veto_shatter: If this property is set to "veto" then the cell will
+      be unaffected by the Shatter spell.
 
 Lua API reference
 -----------------