improved serialization

include/omath/pathfinding/navigation_mesh.hpp

@@ -7,6 +7,7 @@
 #include "omath/linear_algebra/vector3.hpp"
 #include <expected>
 #include <string>
+#include <unordered_map>
 #include <vector>
 
 namespace omath::pathfinding
@@ -28,9 +29,9 @@ namespace omath::pathfinding
         [[nodiscard]]
         bool empty() const;
 
-        [[nodiscard]] std::vector<uint8_t> serialize() const noexcept;
+        [[nodiscard]] std::string serialize() const noexcept;
 
-        void deserialize(const std::vector<uint8_t>& raw) noexcept;
+        void deserialize(const std::string& raw);
 
         std::unordered_map<Vector3<float>, std::vector<Vector3<float>>> m_vertex_map;
     };

source/pathfinding/navigation_mesh.cpp

@@ -3,8 +3,7 @@
 //
 #include "omath/pathfinding/navigation_mesh.hpp"
 #include <algorithm>
-#include <cstring>
-#include <limits>
+#include <sstream>
 #include <stdexcept>
 namespace omath::pathfinding
 {
@@ -30,76 +29,37 @@ namespace omath::pathfinding
         return m_vertex_map.empty();
     }
 
-    std::vector<uint8_t> NavigationMesh::serialize() const noexcept
+    std::string NavigationMesh::serialize() const noexcept
     {
-        std::vector<std::uint8_t> raw;
-
-        // Pre-calculate total size for better performance
-        std::size_t total_size = 0;
+        std::ostringstream oss;
         for (const auto& [vertex, neighbors] : m_vertex_map)
         {
-            total_size += sizeof(vertex) + sizeof(std::uint16_t) + sizeof(Vector3<float>) * neighbors.size();
+            oss << vertex.x << ' ' << vertex.y << ' ' << vertex.z
+                << ' ' << neighbors.size() << '\n';
+            for (const auto& n : neighbors)
+                oss << n.x << ' ' << n.y << ' ' << n.z << '\n';
         }
-        raw.reserve(total_size);
-
-        auto dump_to_vector = [&raw]<typename T>(const T& t)
-        {
-            const auto* byte_ptr = reinterpret_cast<const std::uint8_t*>(&t);
-            raw.insert(raw.end(), byte_ptr, byte_ptr + sizeof(T));
-        };
-
-        for (const auto& [vertex, neighbors] : m_vertex_map)
-        {
-            // Clamp neighbors count to fit in uint16_t (prevents silent data corruption)
-            // NOTE: If neighbors.size() > 65535, only the first 65535 neighbors will be serialized.
-            // This is a limitation of the current serialization format using uint16_t for count.
-            const auto clamped_count =
-                    std::min<std::size_t>(neighbors.size(), std::numeric_limits<std::uint16_t>::max());
-            const auto neighbors_count = static_cast<std::uint16_t>(clamped_count);
-
-            dump_to_vector(vertex);
-            dump_to_vector(neighbors_count);
-
-            // Only serialize up to the clamped count
-            for (std::size_t i = 0; i < clamped_count; ++i)
-                dump_to_vector(neighbors[i]);
-        }
-        return raw;
+        return oss.str();
     }
 
-    void NavigationMesh::deserialize(const std::vector<uint8_t>& raw) noexcept
+    void NavigationMesh::deserialize(const std::string& raw)
     {
-        auto load_from_vector = [](const std::vector<uint8_t>& vec, std::size_t& offset, auto& value)
-        {
-            if (offset + sizeof(value) > vec.size())
-                throw std::runtime_error("Deserialize: Invalid input data size.");
-
-            std::copy_n(vec.data() + offset, sizeof(value), reinterpret_cast<uint8_t*>(&value));
-            offset += sizeof(value);
-        };
-
         m_vertex_map.clear();
+        std::istringstream iss(raw);
 
-        std::size_t offset = 0;
-
-        while (offset < raw.size())
+        Vector3<float> vertex;
+        std::size_t neighbors_count;
+        while (iss >> vertex.x >> vertex.y >> vertex.z >> neighbors_count)
         {
-            Vector3<float> vertex;
-            load_from_vector(raw, offset, vertex);
-
-            std::uint16_t neighbors_count;
-            load_from_vector(raw, offset, neighbors_count);
-
             std::vector<Vector3<float>> neighbors;
             neighbors.reserve(neighbors_count);
-
             for (std::size_t i = 0; i < neighbors_count; ++i)
             {
-                Vector3<float> neighbor;
-                load_from_vector(raw, offset, neighbor);
-                neighbors.push_back(neighbor);
+                Vector3<float> n;
+                if (!(iss >> n.x >> n.y >> n.z))
+                    throw std::runtime_error("Deserialize: Unexpected end of data.");
+                neighbors.push_back(n);
             }
-
             m_vertex_map.emplace(vertex, std::move(neighbors));
         }
     }

tests/general/unit_test_navigation_mesh.cpp

@@ -7,19 +7,18 @@ using namespace omath::pathfinding;
 TEST(NavigationMeshTests, SerializeDeserializeRoundTrip)
 {
     NavigationMesh nav;
-    Vector3<float> a{0.f,0.f,0.f};
-    Vector3<float> b{1.f,0.f,0.f};
-    Vector3<float> c{0.f,1.f,0.f};
+    Vector3<float> a{0.f, 0.f, 0.f};
+    Vector3<float> b{1.f, 0.f, 0.f};
+    Vector3<float> c{0.f, 1.f, 0.f};
 
-    nav.m_vertex_map.emplace(a, std::vector<Vector3<float>>{b,c});
+    nav.m_vertex_map.emplace(a, std::vector<Vector3<float>>{b, c});
     nav.m_vertex_map.emplace(b, std::vector<Vector3<float>>{a});
     nav.m_vertex_map.emplace(c, std::vector<Vector3<float>>{a});
 
-    auto data = nav.serialize();
+    std::string data = nav.serialize();
     NavigationMesh nav2;
     EXPECT_NO_THROW(nav2.deserialize(data));
 
-    // verify neighbors preserved
     EXPECT_EQ(nav2.m_vertex_map.size(), nav.m_vertex_map.size());
     EXPECT_EQ(nav2.get_neighbors(a).size(), 2u);
 }
@@ -27,7 +26,117 @@ TEST(NavigationMeshTests, SerializeDeserializeRoundTrip)
 TEST(NavigationMeshTests, GetClosestVertexWhenEmpty)
 {
     const NavigationMesh nav;
-    constexpr Vector3<float> p{5.f,5.f,5.f};
+    constexpr Vector3<float> p{5.f, 5.f, 5.f};
     const auto res = nav.get_closest_vertex(p);
     EXPECT_FALSE(res.has_value());
 }
+
+TEST(NavigationMeshTests, SerializeEmptyMesh)
+{
+    const NavigationMesh nav;
+    const std::string data = nav.serialize();
+    EXPECT_TRUE(data.empty());
+}
+
+TEST(NavigationMeshTests, DeserializeEmptyString)
+{
+    NavigationMesh nav;
+    EXPECT_NO_THROW(nav.deserialize(""));
+    EXPECT_TRUE(nav.empty());
+}
+
+TEST(NavigationMeshTests, SerializeProducesHumanReadableText)
+{
+    NavigationMesh nav;
+    nav.m_vertex_map.emplace(Vector3<float>{1.f, 2.f, 3.f}, std::vector<Vector3<float>>{{4.f, 5.f, 6.f}});
+
+    const std::string data = nav.serialize();
+
+    // Must contain the vertex and neighbor coords as plain text
+    EXPECT_NE(data.find("1"), std::string::npos);
+    EXPECT_NE(data.find("2"), std::string::npos);
+    EXPECT_NE(data.find("3"), std::string::npos);
+    EXPECT_NE(data.find("4"), std::string::npos);
+    EXPECT_NE(data.find("5"), std::string::npos);
+    EXPECT_NE(data.find("6"), std::string::npos);
+}
+
+TEST(NavigationMeshTests, DeserializeRestoresNeighborValues)
+{
+    NavigationMesh nav;
+    const Vector3<float> v{1.f, 2.f, 3.f};
+    const Vector3<float> n1{4.f, 5.f, 6.f};
+    const Vector3<float> n2{7.f, 8.f, 9.f};
+    nav.m_vertex_map.emplace(v, std::vector<Vector3<float>>{n1, n2});
+
+    NavigationMesh nav2;
+    nav2.deserialize(nav.serialize());
+
+    ASSERT_EQ(nav2.m_vertex_map.count(v), 1u);
+    const auto& neighbors = nav2.get_neighbors(v);
+    ASSERT_EQ(neighbors.size(), 2u);
+    EXPECT_EQ(neighbors[0], n1);
+    EXPECT_EQ(neighbors[1], n2);
+}
+
+TEST(NavigationMeshTests, DeserializeOverwritesPreviousData)
+{
+    NavigationMesh nav;
+    const Vector3<float> v{1.f, 0.f, 0.f};
+    nav.m_vertex_map.emplace(v, std::vector<Vector3<float>>{});
+
+    // Load a different mesh into the same object
+    NavigationMesh other;
+    const Vector3<float> a{10.f, 20.f, 30.f};
+    other.m_vertex_map.emplace(a, std::vector<Vector3<float>>{});
+
+    nav.deserialize(other.serialize());
+
+    EXPECT_EQ(nav.m_vertex_map.size(), 1u);
+    EXPECT_EQ(nav.m_vertex_map.count(v), 0u);
+    EXPECT_EQ(nav.m_vertex_map.count(a), 1u);
+}
+
+TEST(NavigationMeshTests, RoundTripNegativeAndFractionalCoords)
+{
+    NavigationMesh nav;
+    const Vector3<float> v{-1.5f, 0.25f, -3.75f};
+    const Vector3<float> n{100.f, -200.f, 0.001f};
+    nav.m_vertex_map.emplace(v, std::vector<Vector3<float>>{n});
+
+    NavigationMesh nav2;
+    nav2.deserialize(nav.serialize());
+
+    ASSERT_EQ(nav2.m_vertex_map.count(v), 1u);
+    const auto& neighbors = nav2.get_neighbors(v);
+    ASSERT_EQ(neighbors.size(), 1u);
+    EXPECT_NEAR(neighbors[0].x, n.x, 1e-3f);
+    EXPECT_NEAR(neighbors[0].y, n.y, 1e-3f);
+    EXPECT_NEAR(neighbors[0].z, n.z, 1e-3f);
+}
+
+TEST(NavigationMeshTests, GetClosestVertexReturnsNearest)
+{
+    NavigationMesh nav;
+    const Vector3<float> a{0.f, 0.f, 0.f};
+    const Vector3<float> b{10.f, 0.f, 0.f};
+    nav.m_vertex_map.emplace(a, std::vector<Vector3<float>>{});
+    nav.m_vertex_map.emplace(b, std::vector<Vector3<float>>{});
+
+    const auto res = nav.get_closest_vertex({1.f, 0.f, 0.f});
+    ASSERT_TRUE(res.has_value());
+    EXPECT_EQ(res.value(), a);
+}
+
+TEST(NavigationMeshTests, VertexWithNoNeighborsRoundTrip)
+{
+    NavigationMesh nav;
+    const Vector3<float> v{5.f, 5.f, 5.f};
+    nav.m_vertex_map.emplace(v, std::vector<Vector3<float>>{});
+
+    NavigationMesh nav2;
+    nav2.deserialize(nav.serialize());
+
+    ASSERT_EQ(nav2.m_vertex_map.count(v), 1u);
+    EXPECT_TRUE(nav2.get_neighbors(v).empty());
+}