From 5c5e6e1ea71a715f33b2244d10e655d697f2ac81 Mon Sep 17 00:00:00 2001
From: Eric Wasylishen <ewasylishen@gmail.com>
Date: Sun, 19 Jun 2022 17:32:18 -0600
Subject: [PATCH] qbsp: fix brush_clipping_order

---
 qbsp/portals.cc | 5 ++++-
 qbsp/qbsp.cc    | 7 +++----
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/qbsp/portals.cc b/qbsp/portals.cc
index d08c0ff5..db5e142e 100644
--- a/qbsp/portals.cc
+++ b/qbsp/portals.cc
@@ -453,8 +453,11 @@ static void FindPortalSide(portal_t *p)
         node_t *n = p->nodes[j];
         auto p1 = map.planes.at(p->onnode->planenum);
 
-        for (brush_t *brush : n->original_brushes)
+        // iterate the n->original_brushes vector in reverse order, so later brushes
+        // in the map file order are prioritized
+        for (auto it = n->original_brushes.rbegin(); it != n->original_brushes.rend(); ++it)
         {
+            auto *brush = *it;
             if (!options.target_game->contents_contains(brush->contents, viscontents))
                 continue;
             for (face_t &side : brush->faces)
diff --git a/qbsp/qbsp.cc b/qbsp/qbsp.cc
index fb044970..4df23eba 100644
--- a/qbsp/qbsp.cc
+++ b/qbsp/qbsp.cc
@@ -896,15 +896,14 @@ static void ProcessEntity(mapentity_t *entity, const int hullnum)
             tree = BrushBSP(entity, false);
         }
 
-        FreeTreePortals_r(tree->headnode);
-
-        PruneNodes(tree->headnode);
-
         MakeTreePortals(tree);
 
         MarkVisibleSides(tree, entity);
         MakeFaces(tree->headnode);
 
+        FreeTreePortals_r(tree->headnode);
+        PruneNodes(tree->headnode);
+
         if (hullnum <= 0 && entity == map.world_entity() && !map.leakfile) {
             WritePortalFile(tree);
         }