qbsp: merge original brush lists when merging leafs in PruneNodes

common/CMakeLists.txt

@@ -30,7 +30,8 @@ add_library(common STATIC
     ${CMAKE_SOURCE_DIR}/include/common/threads.hh
     ${CMAKE_SOURCE_DIR}/include/common/fs.hh
     ${CMAKE_SOURCE_DIR}/include/common/imglib.hh
-	${CMAKE_SOURCE_DIR}/include/common/settings.hh)
+    ${CMAKE_SOURCE_DIR}/include/common/settings.hh
+    ${CMAKE_SOURCE_DIR}/include/common/vectorutils.hh)
 
 target_link_libraries(common ${CMAKE_THREAD_LIBS_INIT} TBB::tbb fmt::fmt nlohmann_json::nlohmann_json)
 

include/common/vectorutils.hh

@@ -0,0 +1,44 @@
+/*  Copyright (C) 2022 Eric Wasylishen
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ See file, 'COPYING', for details.
+ */
+
+#pragma once
+
+#include <algorithm>
+#include <iterator>
+#include <vector>
+
+template <class T>
+void sort_and_remove_duplicates(T& v)
+{
+    std::sort(v.begin(), v.end());
+
+    auto last = std::unique(v.begin(), v.end());
+    v.erase(last, v.end());
+}
+
+template <class E>
+std::vector<E> concat(const std::vector<E> &a, const std::vector<E> &b)
+{
+    std::vector<E> result;
+    result.reserve(a.size() + b.size());
+
+    std::copy(a.begin(), a.end(), std::back_inserter(result));
+    std::copy(b.begin(), b.end(), std::back_inserter(result));
+    return result;
+}

qbsp/solidbsp.cc

@@ -21,6 +21,7 @@
 
 #include <climits>
 
+#include <common/vectorutils.hh>
 #include <qbsp/brush.hh>
 #include <qbsp/csg4.hh>
 #include <qbsp/map.hh>
@@ -48,6 +49,12 @@ static int mapbrushes;
 
 void ConvertNodeToLeaf(node_t *node, const contentflags_t &contents)
 {
+    // merge the children's brush lists
+    node->original_brushes = concat(
+        node->children[0]->original_brushes,
+        node->children[1]->original_brushes);
+    sort_and_remove_duplicates(node->original_brushes);
+
     node->planenum = PLANENUM_LEAF;
 
     for (int i = 0; i < 2; ++i) {