Here is a list of all files with brief descriptions:

navmap_core
bench
navmap_bench.cpp
include
navmap_core
Combine.hpp	Combining one layer into another with explicit operators, unknown-aware, with provenance
Costs.hpp	Values of a U8 cost layer, as in costmap_2d / Nav2 (so that bridging to them is a copy)
Descriptors.hpp	Geometric descriptors per NavCel (slope, roughness, step, clearance), as layers
DistanceField.hpp	Incremental distance field over a NavMap, updated by the seed cells added and removed instead of recomputed: the cost of an update depends on the area it changes
Geometry.hpp	Low-level geometry utilities for NavMap cells (triangles), AABB and basic queries such as ray-triangle intersection and closest-point
Iterators.hpp	Traversals over the NavCels of a navmap::NavMap: box, disc, ring, polygon, distance order and segment walk
NavMap.hpp	Core container and data structures for EasyNav navigable meshes
Occupancy.hpp	Probabilistic occupancy per NavCel: log-odds with clamping (as OctoMap), stored in an int16 layer in fixed point, and a three-state classification (as UFOMap)
Simplify.hpp	Mesh simplification that keeps the layers: large NavCels where surface and layers are uniform, the original ones where they change
src
navmap_core
Combine.cpp
Descriptors.cpp
DistanceField.cpp
NavMap.cpp
Simplify.cpp
tests
test_adjacency.cpp
test_combine.cpp
test_descriptors.cpp
test_distance_field.cpp
test_geometry.cpp
test_incremental.cpp
test_iterators.cpp
test_layers_unknown_occupancy.cpp
test_links.cpp
test_locate_grid.cpp
test_locate_multisurface.cpp
test_navmap.cpp
test_navmap_assign.cpp
test_navmap_easy.cpp
test_navmap_properties.cpp
test_navmap_uniform_and_closest.cpp
test_raycast_many.cpp
test_simplify.cpp
test_surface_tree.cpp
navmap_ros
include
navmap_ros
conversions.hpp	Conversions between the core NavMap representation and ROS messages
navmap_io.hpp	Save/Load utilities for NavMap to/from disk using ROS 2 CDR serialization
src
navmap_ros
conversions.cpp
navmap_io.cpp
slam_server_app.cpp
tests
test_conversions.cpp
test_from_points.cpp
test_layer_metadata_and_migration.cpp
test_navmap_io.cpp
navmap_rviz_plugin
include
navmap_rviz_plugin
navmap_goal_tool.hpp
navmap_pose_tool.hpp
NavMapDisplay.hpp
src
navmap_rviz_plugin
navmap_goal_tool.cpp
navmap_pose_tool.cpp
NavMapDisplay.cpp