Remove chain-lightning specific LOS test from beam.cc.

There's now a spell-specific _lightning_los which may require
some fine-tuning -- I'm not quite sure of the intention of the
original check.

4 files changed, 10 insertions, 26 deletions

diff --git a/crawl-ref/source/beam.cc b/crawl-ref/source/beam.cc
index 83736773da..59b839ccf3 100644
--- a/crawl-ref/source/beam.cc
+++ b/crawl-ref/source/beam.cc
@@ -2832,29 +2832,6 @@ void fire_tracer(const monsters *monster, bolt &pbolt, bool explode_only)
     pbolt.is_tracer = false;
 }
 
-/**
- * Checks whether target is in sight of source.
- *
- * Only used from cast_chain_lightning currently.
- * XXX: Move to los.cc; integrate with other LOS code.
- */
-bool check_line_of_sight(const coord_def& source, const coord_def& target)
-{
-    const int dist = grid_distance(source, target);
-
-    // Can always see one square away.
-    if (dist <= 1)
-        return (true);
-
-    // Currently we limit the range to 8.
-    if (dist > MONSTER_LOS_RANGE)
-        return (false);
-
-    // Note that we are guaranteed to be within the player LOS range,
-    // so fallback is unnecessary.
-    return exists_ray(source, target);
-}
-
 // When a mimic is hit by a ranged attack, it teleports away (the slow
 // way) and changes its appearance - the appearance change is in
 // monster_teleport() in mstuff2.cc.
diff --git a/crawl-ref/source/beam.h b/crawl-ref/source/beam.h
index 56908cc023..41f410c8ac 100644
--- a/crawl-ref/source/beam.h
+++ b/crawl-ref/source/beam.h
@@ -291,7 +291,6 @@ bool napalm_monster(monsters *monster, kill_category who, int levels = 1,
                     bool verbose = true);
 void fire_tracer( const monsters *monster, struct bolt &pbolt,
                   bool explode_only = false );
-bool check_line_of_sight( const coord_def& source, const coord_def& target );
 void mimic_alert( monsters *mimic );
 bool zapping(zap_type ztype, int power, bolt &pbolt,
              bool needs_tracer = false, const char* msg = NULL);
diff --git a/crawl-ref/source/losparam.h b/crawl-ref/source/losparam.h
index 4d5bc141e1..82dee24519 100644
--- a/crawl-ref/source/losparam.h
+++ b/crawl-ref/source/losparam.h
@@ -60,6 +60,7 @@ struct bounds_radius_sq : bounds_func
         : radius_sq(r_sq) {}
     bool operator()(const coord_def& p) const;
 };
+static bounds_radius_sq bds_maxlos(LOS_RADIUS);
 
 // LOS bounded by current global LOS radius.
 struct bounds_los_radius : bounds_func
diff --git a/crawl-ref/source/spells1.cc b/crawl-ref/source/spells1.cc
index 0e71583ffb..e49807379a 100644
--- a/crawl-ref/source/spells1.cc
+++ b/crawl-ref/source/spells1.cc
@@ -297,6 +297,13 @@ void cast_fire_storm(int pow, bolt &beam)
     viewwindow(true, false);
 }
 
+bool _lightning_los(const coord_def& source, const coord_def& target)
+{
+    // XXX: currently bounded by circular LOS radius;
+    // XXX: adapt opacity -- allow passing clouds.
+    return (exists_ray(source, target, opc_solid, bds_maxlos));
+}
+
 void cast_chain_lightning(int pow)
 {
     bolt beam;
@@ -350,7 +357,7 @@ void cast_chain_lightning(int pow)
             if (dist > min_dist)
                 continue;
 
-            if (!check_line_of_sight(source, monster->pos()))
+            if (_lightning_los(source, monster->pos()))
                 continue;
 
             count++;
@@ -387,7 +394,7 @@ void cast_chain_lightning(int pow)
             if ((target.x == -1
                     || dist < min_dist
                     || (dist == min_dist && one_chance_in(count + 1)))
-                && check_line_of_sight(source, you.pos()))
+                && _lightning_los(source, you.pos()))
             {
                 target = you.pos();
             }