How scan segments link together through RTK, control points, or both, and the two configurations that always fail.
Section 1
How Segments Connect
Every segment in a fusion project must link to at least one neighbor through valid RTK or matching control points. If any segment has no connection, it is excluded from the fused result. Use this diagram to verify your connection plan before going to site. Full detail is in 5.1 Fundamentals and 5.3 Collection.
Section 2
Fusion Connection Patterns
Section 3
Legend and Specifications
Segment Types
Segment State
Meaning
RTK-anchored
Fixed RTK achieved throughout the segment. Pulls global coordinates into the fused output.
CP-anchored
No RTK or RTK invalid. Connects to neighbors only through identically named control points.
Isolated
No RTK, no shared control points with any neighbor. Excluded from the fused output.
Connection Types
Type
Field Requirement
RTK link
Both segments achieved Fixed RTK with at least 100 ft (30 m) of effective coverage and 33 ft (10 m) of movement while Fixed. Zigzag path preferred over straight line.
CP link
At least one identically named control point in the overlap zone of both segments. For K1/L2 Pro, one shared point per junction is sufficient; a second adds redundancy. For PortalCam, minimum 3 CPs in L-shaped layout. Narrow Mode: two minimum, 16 ft (5 m) apart.
Hybrid link
Mixed: one segment RTK, the other CP. Both methods present at the boundary.
Outputs
Coordinate Result
When It Happens
Global coordinates
Any segment in the fusion job carried valid RTK. The coordinate frame propagates to the entire fused output.
Relative coordinates
No segment carried valid RTK. The fused output is internally consistent but has no absolute position.
Section 4
Choosing a Connection Method
Applies to both processing pipelines, with one device exception. The connection patterns above apply equally to LixelStudio (point clouds for CAD, BIM, survey) and LCC Studio (3DGS for visualization, virtual tours, LCC for BIM Revit plugin). Field collection is the same. Device support differs: LixelStudio Map Fusion supports L2 Pro, K2, and K1. LCC Studio Map Fusion supports PortalCam, L2 Pro, and K1; the K2 is not yet supported in LCC Studio Map Fusion (K2 in LCC Studio is currently limited to Single Model reconstruction and Spatial Recognition with a 90-minute single-scene cap). See 9.3 LCC Studio Map Fusion for 3DGS processing steps and current K2 status.
Note on control point tolerances: the specs above reflect L2 Pro, K2, and K1 best practices where the device is placed directly on the ground (same form factor and procedure across all three devices). PortalCam uses a different marking procedure and has wider official tolerances: within 1.6 ft (0.5 m) horizontal, ±20 degrees orientation, and approximately 4 in (10 cm) height consistency. See 7.2 Advanced PortalCam Scanning for PortalCam control point procedure.
RTK Connection
HowEach segment independently achieves Fixed RTK with at least 100 ft of effective coverage. A zigzag scanning path produces better results than a straight line. The shared coordinate system aligns them.
WhySimplest method. No naming conventions, no coordination between segments. Eliminates the most common failure cause: CP naming errors.
OutputGlobal coordinates.
Best forOutdoor projects with reliable satellite coverage.
Control Point Connection
HowAdjacent segments share identically named points in the overlap zone. Names are the only matching mechanism. Device must be on the ground when marking. For K1/L2 Pro, the procedure uses 1 shared point per junction; a second adds redundancy. For PortalCam, a minimum of 3 CPs in an L-shaped layout is required.
WhyWorks everywhere, including GPS-denied environments. Combined with surveyed GCPs, delivers absolute accuracy indoors.
OutputRelative coordinates, unless at least one segment also has RTK.
Best forIndoor, underground, tunnels.
Hybrid Connection
HowRTK where available, CPs where not. Methods can be mixed in the same project. Any segment with RTK gives the entire result global coordinates.
WhyMost real projects have both indoor and outdoor. If RTK drops to Float, a shared CP saves the connection.
OutputGlobal coordinates (if any segment has valid RTK).
Best forMixed environments. Most common approach for large facilities.
Invalid: No Connection
Isolated segmentNo RTK, no shared CPs. Excluded from the fused output.
PreventionPlan fallback CPs at every segment break, even on RTK projects. Details in 5.6 Troubleshooting.
Section 5
The Overlap Zone
The One Rule That Governs All Fusion
Every segment must connect to at least one neighbor through valid RTK or matching control points. A segment with no connection is excluded. This must be decided before collection begins because RTK data and CP names cannot be added after the scan.
Plan 65 to 100 ft (20 to 30 m) of overlap, not exactly 50 ft. The 50 ft (15 m) minimum is a hard limit, but barely meeting it is risky because small field adjustments can push the actual overlap below the threshold. An overlap zone that falls short at 40 ft causes fusion failure. Building in a buffer protects against this. The overlap zone must also contain rich, stable surface features: lobbies, furnished rooms, equipment clusters, corridor intersections. Avoid stairways, narrow corridors, glass or mirror surfaces, monochrome or dark areas, and high-traffic zones where objects move between segment collections. Feature-poor overlap zones fail even when distance requirements are met. Full planning guidance is in 5.2 Pre-Project Planning.
Section 6
Need to Combine More Than 10 Scans?
Break the Project Into Multiple Fusion Jobs
Map Fusion is limited to 10 segments and 200 minutes per job. For larger sites, process groups of up to 10 as separate fusion jobs, then combine the outputs downstream.
Point Cloud (LixelStudio)
Export each fused result as E57 or LAS. Merge in CloudCompare, Autodesk ReCap Pro, or Leica Cyclone. RTK-based jobs share a coordinate system and align on import.
3DGS (LCC Studio)
Each fused model (PortalCam, L2 Pro, or K1 workflows) can be viewed in LCC Studio, published to LixelWeb, or imported into Revit via the LCC for BIM plugin. RTK-based jobs align automatically. K2 is not yet supported in LCC Studio Map Fusion; for K2 3DGS projects requiring multi-job assembly, plan around the Single Model 90-minute cap until LCC Studio adds K2 Map Fusion support.
Field Planning
Plan overlap zones between the last segment of one job and the first segment of the next. Mark CPs at cross-job boundaries if RTK is unavailable.
Module 5 complete. You have covered Map Fusion end to end, from fundamentals through troubleshooting and visual reference. Module 6 advances to L2 Pro and K2 device-specific scanning techniques.
