Make some passed references const.

A couple of the Feawn functions were passed read-only arguments
(coordinate center, etc.) as non-const references, which leaked out
to require you.pos() to be non-const.

4 files changed, 18 insertions, 17 deletions

diff --git a/crawl-ref/source/effects.cc b/crawl-ref/source/effects.cc
index 92fa7690d0..9dbced7c40 100644
--- a/crawl-ref/source/effects.cc
+++ b/crawl-ref/source/effects.cc
@@ -4305,12 +4305,12 @@ static int _arc_decomposition(const coord_def & pos, int n_arcs)
     return static_cast<int> (theta / arc_angle);
 }
 
-int place_ring(std::vector<coord_def> & ring_points,
-                coord_def & origin,
-                mgen_data & prototype,
-                int n_arcs,
-                int arc_occupancy,
-                int & seen_count)
+int place_ring(std::vector<coord_def> &ring_points,
+               const coord_def &origin,
+               mgen_data prototype,
+               int n_arcs,
+               int arc_occupancy,
+               int &seen_count)
 {
     std::random_shuffle(ring_points.begin(),
                         ring_points.end());
@@ -4349,7 +4349,7 @@ int place_ring(std::vector<coord_def> & ring_points,
 // Collect lists of points that are within LOS (under the given env map),
 // unoccupied, and not solid (walls/statues).
 void collect_radius_points(std::vector<std::vector<coord_def> > &radius_points,
-                           coord_def & origin, env_show_grid & losgrid)
+                           const coord_def &origin, const env_show_grid &losgrid)
 {
 
     radius_points.clear();
diff --git a/crawl-ref/source/effects.h b/crawl-ref/source/effects.h
index fe13baee0f..dd23f6ba67 100644
--- a/crawl-ref/source/effects.h
+++ b/crawl-ref/source/effects.h
@@ -42,17 +42,17 @@ int spawn_corpse_mushrooms(item_def &corpse,
                            bool distance_as_time = false);
 
 struct mgen_data;
-int place_ring(std::vector<coord_def> & ring_points,
-                coord_def & origin,
-                mgen_data & prototype,
-                int n_arcs,
-                int arc_occupancy,
-                int & seen_count);
+int place_ring(std::vector<coord_def>& ring_points,
+               const coord_def& origin,
+               mgen_data prototype,
+               int n_arcs,
+               int arc_occupancy,
+               int& seen_count);
 
 // Collect lists of points that are within LOS (under the given losgrid),
 // unoccupied, and not solid (walls/statues).
 void collect_radius_points(std::vector<std::vector<coord_def> > &radius_points,
-                           coord_def & origin, env_show_grid & losgrid);
+                           const coord_def &origin, const env_show_grid &losgrid);
 
 void random_uselessness(int scroll_slot = -1);
 
diff --git a/crawl-ref/source/spells2.cc b/crawl-ref/source/spells2.cc
index b0f2f38563..e91d251949 100644
--- a/crawl-ref/source/spells2.cc
+++ b/crawl-ref/source/spells2.cc
@@ -2106,7 +2106,7 @@ void point_point(std::vector<coord_def> & origins,
 // to calculate the distances in question. In practice it should be called for
 // at most 7 searches since 8 (all adjacent free, > 8 monsters in view) can be
 // special cased easily.
-bool prioritise_adjacent(coord_def & target, std::vector<coord_def> & candidates)
+bool prioritise_adjacent(const coord_def &target, std::vector<coord_def> & candidates)
 {
     radius_iterator los_it(target, LOS_RADIUS, true, true, true);
 
@@ -2114,7 +2114,7 @@ bool prioritise_adjacent(coord_def & target, std::vector<coord_def> & candidates
     // collect hostile monster positions in LOS
     for ( ; los_it; ++los_it)
     {
-        monsters * hostile = monster_at(*los_it);
+        monsters *hostile = monster_at(*los_it);
 
         if (hostile && hostile->attitude == ATT_HOSTILE)
             mons_positions.push_back(hostile->pos());
diff --git a/crawl-ref/source/spells2.h b/crawl-ref/source/spells2.h
index 124032f9f4..dcc02dfed2 100644
--- a/crawl-ref/source/spells2.h
+++ b/crawl-ref/source/spells2.h
@@ -32,7 +32,8 @@ int create_plant(coord_def & target);
 //bool plant_from_fruit();
 bool sunlight();
 
-bool prioritise_adjacent(coord_def & target, std::vector<coord_def> & candidates);
+bool prioritise_adjacent(const coord_def &target,
+                         std::vector<coord_def> &candidates);
 bool plant_ring_from_fruit();
 
 int rain(const coord_def &target);