monster_near_iterator

Does the "in view" part of functionality of monster_iterator, is simpler,
allows using los models other than LOS_DEFAULT, and gets rid of a lot of
uses of get_los().

The code is nearly identical as actor_near_iterator, but the old delegation
used more code than either of those.  Still, perhaps templating could work?

This commit also fixes a buttload of ignoring invis / see invis / sense invis
(ie, visible_to()) and act-through-glass bugs.

1 files changed, 64 insertions, 0 deletions

diff --git a/crawl-ref/source/act-iter.cc b/crawl-ref/source/act-iter.cc
index d5e0b3e41e..8e62e1acdb 100644
--- a/crawl-ref/source/act-iter.cc
+++ b/crawl-ref/source/act-iter.cc
@@ -68,3 +68,67 @@ void actor_near_iterator::advance()
              return;
     while (!valid(**this));
 }
+
+//////////////////////////////////////////////////////////////////////////
+
+monster_near_iterator::monster_near_iterator(coord_def c, los_type los)
+    : center(c), _los(los), viewer(nullptr), i(0)
+{
+    if (!valid(&menv[0]))
+        advance();
+}
+
+monster_near_iterator::monster_near_iterator(const actor *a, los_type los)
+    : center(a->pos()), _los(los), viewer(a), i(0)
+{
+    if (!valid(&menv[0]))
+        advance();
+}
+
+monster_near_iterator::operator bool() const
+{
+    return valid(**this);
+}
+
+monster* monster_near_iterator::operator*() const
+{
+    if (i < MAX_MONSTERS)
+        return &menv[i];
+    else
+        return nullptr;
+}
+
+monster* monster_near_iterator::operator->() const
+{
+    return **this;
+}
+
+monster_near_iterator& monster_near_iterator::operator++()
+{
+    advance();
+    return *this;
+}
+
+monster_near_iterator monster_near_iterator::operator++(int)
+{
+    monster_near_iterator copy = *this;
+    ++(*this);
+    return copy;
+}
+
+bool monster_near_iterator::valid(const monster* a) const
+{
+    if (!a || !a->alive())
+        return false;
+    if (viewer && !a->visible_to(a))
+        return false;
+    return cell_see_cell(center, a->pos(), _los);
+}
+
+void monster_near_iterator::advance()
+{
+    do
+         if (++i >= MAX_MONSTERS)
+             return;
+    while (!valid(**this));
+}