Make Swamp prettier. (Tiles)

Adds a new member to the packed_cell called swamp_tree_water. This
boolean value triggers the following behaviour:

1. Trees in Swamp are drawn on top of TILE_DNGN_SHALLOW_WATER. The
   reasoning here is that trees, when destroyed, are replaced by shallow
   water. It does look a *lot* better, in my opinion, to have the water
   underneath them.
2. The boolean value is stored for DNGN_TREE, DNGN_SHALLOW_WATER and
   DNGN_DEEP_WATER in the Swamp. This value is then passed into the
   wave/shore packing functions and is used to suppress shore overlays.

All in all, I'm very happy with the result.

I think Swamp could have further improvements by changing the tree tile
to be a large mangrove tile instead. The current tree looks great in the
dungeon, but the large amount of them in Swamp combined with the
background (previously floor, currently shallow water) makes them look
very sparse.

1 files changed, 5 insertions, 2 deletions

diff --git a/crawl-ref/source/tiledgnbuf.h b/crawl-ref/source/tiledgnbuf.h
index 062f8cc7a5..46f322cefa 100644
--- a/crawl-ref/source/tiledgnbuf.h
+++ b/crawl-ref/source/tiledgnbuf.h
@@ -25,9 +25,11 @@ struct packed_cell
     bool is_haloed;
     bool is_moldy;
     bool is_sanctuary;
+    bool swamp_tree_water;
 
     packed_cell() : num_dngn_overlay(0), is_bloody(false), is_silenced(false),
-                    is_haloed(false), is_moldy(false), is_sanctuary(false) {}
+                    is_haloed(false), is_moldy(false), is_sanctuary(false),
+                    swamp_tree_water (false) {}
 
     packed_cell(const packed_cell* c) : num_dngn_overlay(c->num_dngn_overlay),
                                         fg(c->fg), bg(c->bg), flv(c->flv),
@@ -35,7 +37,8 @@ struct packed_cell
                                         is_silenced(c->is_silenced),
                                         is_haloed(c->is_haloed),
                                         is_moldy(c->is_moldy),
-                                        is_sanctuary(c->is_sanctuary) {}
+                                        is_sanctuary(c->is_sanctuary),
+                                        swamp_tree_water(c->swamp_tree_water) {}
 
     void clear ();
 };