From b477775e1602893c6586b0525ed104b1b383636e Mon Sep 17 00:00:00 2001
From: elsid <elsid.mail@gmail.com>
Date: Sun, 4 Nov 2018 18:34:31 +0300
Subject: [PATCH] Use callback to iterate over chunks

---
 components/detournavigator/chunkytrimesh.hpp |  6 +-
 components/detournavigator/makenavmesh.cpp   | 93 ++++++++++----------
 2 files changed, 49 insertions(+), 50 deletions(-)

diff --git a/components/detournavigator/chunkytrimesh.hpp b/components/detournavigator/chunkytrimesh.hpp
index c9d35f086..9f6275ec8 100644
--- a/components/detournavigator/chunkytrimesh.hpp
+++ b/components/detournavigator/chunkytrimesh.hpp
@@ -50,8 +50,8 @@ namespace DetourNavigator
         ChunkyTriMesh& operator=(const ChunkyTriMesh&) = delete;
 
         /// Returns the chunk indices which overlap the input rectable.
-        template <class OutputIterator>
-        void getChunksOverlappingRect(const Rect& rect, OutputIterator out) const
+        template <class Function>
+        void forEachChunksOverlappingRect(const Rect& rect, Function&& function) const
         {
             // Traverse tree
             for (std::size_t i = 0; i < mNodes.size(); )
@@ -61,7 +61,7 @@ namespace DetourNavigator
                 const bool isLeafNode = node->mOffset >= 0;
 
                 if (isLeafNode && overlap)
-                    *out++ = i;
+                    function(i);
 
                 if (overlap || isLeafNode)
                     i++;
diff --git a/components/detournavigator/makenavmesh.cpp b/components/detournavigator/makenavmesh.cpp
index 7072f2a23..3ee730386 100644
--- a/components/detournavigator/makenavmesh.cpp
+++ b/components/detournavigator/makenavmesh.cpp
@@ -149,62 +149,61 @@ namespace
         std::vector<unsigned char> areas(chunkyMesh.getMaxTrisPerChunk(), AreaType_null);
         const osg::Vec2f tileBoundsMin(config.bmin[0], config.bmin[2]);
         const osg::Vec2f tileBoundsMax(config.bmax[0], config.bmax[2]);
-        std::vector<std::size_t> cids;
-        chunkyMesh.getChunksOverlappingRect(Rect {tileBoundsMin, tileBoundsMax}, std::back_inserter(cids));
+        bool result = false;
 
-        if (cids.empty())
-            return false;
+        chunkyMesh.forEachChunksOverlappingRect(Rect {tileBoundsMin, tileBoundsMax},
+            [&] (const std::size_t cid)
+            {
+                const auto chunk = chunkyMesh.getChunk(cid);
 
-        for (const auto cid : cids)
-        {
-            const auto chunk = chunkyMesh.getChunk(cid);
+                std::fill(
+                    areas.begin(),
+                    std::min(areas.begin() + static_cast<std::ptrdiff_t>(chunk.mSize),
+                    areas.end()),
+                    AreaType_null
+                );
 
-            std::fill(
-                areas.begin(),
-                std::min(areas.begin() + static_cast<std::ptrdiff_t>(chunk.mSize),
-                areas.end()),
-                AreaType_null
-            );
+                rcMarkWalkableTriangles(
+                    &context,
+                    config.walkableSlopeAngle,
+                    recastMesh.getVertices().data(),
+                    static_cast<int>(recastMesh.getVerticesCount()),
+                    chunk.mIndices,
+                    static_cast<int>(chunk.mSize),
+                    areas.data()
+                );
 
-            rcMarkWalkableTriangles(
-                &context,
-                config.walkableSlopeAngle,
-                recastMesh.getVertices().data(),
-                static_cast<int>(recastMesh.getVerticesCount()),
-                chunk.mIndices,
-                static_cast<int>(chunk.mSize),
-                areas.data()
-            );
+                for (std::size_t i = 0; i < chunk.mSize; ++i)
+                    areas[i] = chunk.mAreaTypes[i];
 
-            for (std::size_t i = 0; i < chunk.mSize; ++i)
-                areas[i] = chunk.mAreaTypes[i];
+                rcClearUnwalkableTriangles(
+                    &context,
+                    config.walkableSlopeAngle,
+                    recastMesh.getVertices().data(),
+                    static_cast<int>(recastMesh.getVerticesCount()),
+                    chunk.mIndices,
+                    static_cast<int>(chunk.mSize),
+                    areas.data()
+                );
 
-            rcClearUnwalkableTriangles(
-                &context,
-                config.walkableSlopeAngle,
-                recastMesh.getVertices().data(),
-                static_cast<int>(recastMesh.getVerticesCount()),
-                chunk.mIndices,
-                static_cast<int>(chunk.mSize),
-                areas.data()
-            );
+                const auto trianglesRasterized = rcRasterizeTriangles(
+                    &context,
+                    recastMesh.getVertices().data(),
+                    static_cast<int>(recastMesh.getVerticesCount()),
+                    chunk.mIndices,
+                    areas.data(),
+                    static_cast<int>(chunk.mSize),
+                    solid,
+                    config.walkableClimb
+                );
 
-            const auto trianglesRasterized = rcRasterizeTriangles(
-                &context,
-                recastMesh.getVertices().data(),
-                static_cast<int>(recastMesh.getVerticesCount()),
-                chunk.mIndices,
-                areas.data(),
-                static_cast<int>(chunk.mSize),
-                solid,
-                config.walkableClimb
-            );
+                if (!trianglesRasterized)
+                    throw NavigatorException("Failed to create rasterize triangles from recast mesh for navmesh");
 
-            if (!trianglesRasterized)
-                throw NavigatorException("Failed to create rasterize triangles from recast mesh for navmesh");
-        }
+                result = true;
+            });
 
-        return true;
+        return result;
     }
 
     void rasterizeWaterTriangles(rcContext& context, const osg::Vec3f& agentHalfExtents, const RecastMesh& recastMesh,