allow iterating over branches in a non-enum order (8742)

This allows us to have a consistent and logical ordering of branches
without requiring the branch enum itself to be reordered (which could
have save compatibility implications). The new ordering of branches just
moves Depths to the place in the ordering that it already is planned to
go on the next major save compat bump, but other changes are possible,
if desired. All places in the code that iterate over branches have been
updated to use the new iterator except for code dealing with save files,
which still uses enum order, so that we can change the display ordering
without affecting saves.

1 files changed, 4 insertions, 4 deletions

diff --git a/crawl-ref/source/abyss.cc b/crawl-ref/source/abyss.cc
index e4b7dfc866..2d96fc22e0 100644
--- a/crawl-ref/source/abyss.cc
+++ b/crawl-ref/source/abyss.cc
@@ -969,13 +969,13 @@ static bool _in_wastes(const coord_def &p)
 static level_id _get_random_level()
 {
     vector<level_id> levels;
-    for (int i = BRANCH_DUNGEON; i < NUM_BRANCHES; ++i)
+    for (branch_iterator it; it; ++it)
     {
-        if (i == BRANCH_ABYSS || i == BRANCH_SHOALS)
+        if (it->id == BRANCH_ABYSS || it->id == BRANCH_SHOALS)
             continue;
-        for (int j = 1; j <= brdepth[i]; ++j)
+        for (int j = 1; j <= brdepth[it->id]; ++j)
         {
-            const level_id id(static_cast<branch_type>(i), j);
+            const level_id id(it->id, j);
             if (is_existing_level(id))
                 levels.push_back(id);
         }