Introduce actor::see_cell.

Implemented using the existing LOS functions for now. In particular,
monster-monster visibility still uses num_feats_between.

5 files changed, 19 insertions, 14 deletions

diff --git a/crawl-ref/source/actor.h b/crawl-ref/source/actor.h
index a760742786..f8ff1ad599 100644
--- a/crawl-ref/source/actor.h
+++ b/crawl-ref/source/actor.h
@@ -102,6 +102,7 @@ public:
     virtual bool can_see_invisible() const = 0;
     virtual bool invisible() const = 0;
     virtual bool visible_to(const actor *looker) const = 0;
+    virtual bool see_cell(const coord_def &c) const = 0;
     virtual bool can_see(const actor *target) const = 0;
     virtual bool is_icy() const = 0;
     virtual bool is_fiery() const = 0;
diff --git a/crawl-ref/source/mon-util.cc b/crawl-ref/source/mon-util.cc
index 9ad32ef80d..4ed5d9b690 100644
--- a/crawl-ref/source/mon-util.cc
+++ b/crawl-ref/source/mon-util.cc
@@ -8043,18 +8043,19 @@ bool monsters::mon_see_cell(const coord_def& p, bool reach) const
                                true, true));
 }
 
-bool monsters::can_see(const actor *targ) const
+bool monsters::see_cell(const coord_def &c) const
 {
-    if (this == targ)
-        return (visible_to(targ));
-
-    if (!targ->visible_to(this))
-        return (false);
+    // XXX: using env.show since that's been filled anywa.
+    if (c == you.pos())
+        return (you.see_cell(pos()));
 
-    if (targ->atype() == ACT_PLAYER)
-        return (mons_near(this));
+    // TODO: Proper monster LOS.
+    return (mon_see_cell(c));
+}
 
-    return (mon_see_cell(targ->pos()));
+bool monsters::can_see(const actor *targ) const
+{
+    return (targ->visible_to(this) && see_cell(targ->pos()));
 }
 
 bool monsters::can_mutate() const
diff --git a/crawl-ref/source/monster.h b/crawl-ref/source/monster.h
index b942b2d91e..860cf1ae0c 100644
--- a/crawl-ref/source/monster.h
+++ b/crawl-ref/source/monster.h
@@ -301,6 +301,7 @@ public:
     bool can_see_invisible() const;
     bool visible_to(const actor *looker) const;
     bool mon_see_cell(const coord_def& pos, bool reach = false) const;
+    bool see_cell(const coord_def& c) const;
     bool can_see(const actor *target) const;
     bool is_icy() const;
     bool is_fiery() const;
diff --git a/crawl-ref/source/player.cc b/crawl-ref/source/player.cc
index 3892682d80..452c16a57c 100644
--- a/crawl-ref/source/player.cc
+++ b/crawl-ref/source/player.cc
@@ -7362,16 +7362,17 @@ bool player::visible_to(const actor *looker) const
     return mons_player_visible(mon);
 }
 
+bool player::see_cell(const coord_def &c) const
+{
+    return (::see_cell(c));
+}
+
 bool player::can_see(const actor *target) const
 {
     if (crawl_state.arena)
         return target->visible_to(this);
 
-    if (this == target)
-        return visible_to(target);
-
-    const monsters* mon = dynamic_cast<const monsters*>(target);
-    return (mons_near(mon) && target->visible_to(this));
+    return (target->visible_to(this) && see_cell(target->pos()));
 }
 
 bool player::backlit(bool check_haloed) const
diff --git a/crawl-ref/source/player.h b/crawl-ref/source/player.h
index 0c77c6894d..d37495b532 100644
--- a/crawl-ref/source/player.h
+++ b/crawl-ref/source/player.h
@@ -301,6 +301,7 @@ public:
     bool invisible() const;
     bool can_see_invisible() const;
     bool visible_to(const actor *looker) const;
+    bool see_cell(const coord_def &c) const;
     bool can_see(const actor *target) const;
     bool is_icy() const;
     bool is_fiery() const;