Function BuildDirtyBounds

Source/Engine/Navigation/NavMeshBuilder.cpp:903–1048

}

void BuildDirtyBounds(Scene* scene, NavMesh* navMesh, const BoundingBox& dirtyBounds, bool rebuild)
{
    const float tileSize = GetTileSize();
    NavMeshRuntime* runtime = navMesh->GetRuntime();
    Matrix worldToNavMesh;
    Matrix::RotationQuaternion(runtime->Properties.Rotation, worldToNavMesh);

    // Align dirty bounds to tile size
    BoundingBox dirtyBoundsNavMesh;
    BoundingBox::Transform(dirtyBounds, worldToNavMesh, dirtyBoundsNavMesh);
    dirtyBoundsNavMesh.Minimum = Float3::Floor(dirtyBoundsNavMesh.Minimum / tileSize) * tileSize;
    dirtyBoundsNavMesh.Maximum = Float3::Ceil(dirtyBoundsNavMesh.Maximum / tileSize) * tileSize;

    // Calculate tiles range for the given navigation dirty bounds (aligned to tiles size)
    const Int3 tilesMin(dirtyBoundsNavMesh.Minimum / tileSize);
    const Int3 tilesMax(dirtyBoundsNavMesh.Maximum / tileSize);
    const int32 tilesXZ = (tilesMax.X - tilesMin.X) * (tilesMax.Z - tilesMin.Z);

    {
        PROFILE_CPU_NAMED("Prepare");
        runtime->Locker.Lock();

        // Prepare scene data and navmesh
        rebuild |= Math::NotNearEqual(navMesh->Data.TileSize, tileSize);
        if (rebuild)
        {
            runtime->Locker.Unlock();
            CancelNavMeshTileBuildTasks(runtime);
            runtime->Locker.Lock();

            // Remove all tiles from navmesh runtime
            runtime->RemoveTiles(navMesh);
            runtime->SetTileSize(tileSize);
            runtime->EnsureCapacity(tilesXZ);

            // Remove all tiles from navmesh data
            navMesh->Data.TileSize = tileSize;
            navMesh->Data.Tiles.Clear();
            navMesh->Data.Tiles.EnsureCapacity(tilesXZ);
            navMesh->IsDataDirty = true;
        }
        else
        {
            // Ensure to have enough memory for tiles
            runtime->EnsureCapacity(tilesXZ);
        }

        runtime->Locker.Unlock();
    }

    // Initialize nav mesh configuration
    rcConfig config;
    InitConfig(config, navMesh);

    // Generate all tiles that intersect with the navigation volume bounds
    {
        PROFILE_CPU_NAMED("StartBuildingTiles");