Introduction

This article describes the troubleshooting steps and best practices for creating robust Site Models in NavVis IVION. It addresses common pitfalls (e.g., misassigned floors, POI visibility, irregular/overlapping levels) and gives repeatable diagnostics and fixes.

What a good Site Model must guarantee

• Clear building hierarchy: sites → buildings → floors → rooms/areas reflect physical reality and data bundles.

• Accurate floor extents and elevations: outlines contain only the intended areas per floor; vertical ranges reflect capture reality.

• Correct dataset-to-entity assignment: each dataset/point cloud appears only on the intended floor(s).

• Consistent navigation and POI visibility: POIs and vector layers appear on the right floor and are not occluded by incorrect overlaps.

Quick diagnostic flow

1. Open Site Model Editor and toggle visibility per building/floor to isolate the problem entity (which level shows the wrong data?).

2. Check entity assignments: confirm datasets are linked to the intended floors only; look for duplicates across adjacent floors.

3. Review floor elevation parameters: verify min/max elevation ranges and expected vertical ordering between floors/buildings.

4. Inspect outlines: ensure polygons/rectangles do not overlap unintentionally; use “cut a hole” only where another building intrudes.

5. Validate with Map/Quality views: confirm that 2D/Color maps align with floor boundaries and that POIs show where expected.

Note: If auto-generation was used, remember that subsequent actions can overwrite manual edits. Lock your intended structure, then re-apply precise manual adjustments.

Common issues and how to fix them

1. Point clouds appear on the wrong floor

Issue: First-floor data shows up on the second floor (or vice versa).

• Why it happens: Incorrect dataset-to-floor assignment or floor elevation ranges that encompass parts of adjacent levels.

• Fix:

  • Reassign datasets in Site Model Editor so each bundle is linked only to its intended floor.

  • Tighten floor elevation ranges to eliminate unintended vertical overlap.

2. POIs visible on the wrong level or missing

Issue: POIs placed near stair cores or mezzanines show on adjacent floors or disappear.

• Why it happens: Overlapping floor outlines, elevation ranges that capture the same vertical space, or partial floors modeled as full rectangles.

• Fix:

  • Trim outlines precisely to the walkable extents per floor; avoid unnecessary overlap across levels.

  • If split-level/partial floors are needed and overlapping polygons are not supported, model them using multiple buildings or discrete floor slices with consistent naming (reference: internal guidance).

3. Irregular/overlapping floor plans

Symptom: Complex building geometry cannot be cleanly represented with rectangular floors; overlapping floors cause visibility conflicts.

• Issue: Current floor entity model favors simple polygons; non-orthogonal or partial slabs require careful decomposition.

• Fix:

  • Decompose one physical level into multiple non-overlapping floor entities (slices). Use identical naming where instructed to unify display, and ensure vertical ranges don’t overlap adjacent levels.

  • Use “cut a hole” in a building footprint only to carve out embedded atria/voids or to place an inner building, not to create lateral overlaps across different levels.

4. Auto-generated Site Model is inaccurate

Symptom: After auto-generation, floor boundaries are too broad, elevations are off, or rooms bleed into adjacent zones.

• Fix:

  • Lock the overall building structure, then manually refine floor outlines and heights. Verify after each iterative change by toggling visibility per floor.

  • Re-run auto-generation only when necessary and be aware it can overwrite manual edits.

Elevation and outline tuning checklist

• Confirm vertical order: no crossing ranges between adjacent floors; maintain small, intentional gaps where needed to avoid overlap.

• Snap outlines to real boundaries: stair cores, shafts, and atria should be excluded from floors where not walkable.

• One dataset, one floor: prevent the same bundle from being linked to multiple levels unless explicitly required by multi-level captures.

Advanced troubleshooting: floor assignment vs. control/alignment

If misplacement persists after correcting the Site Model, investigate dataset alignment and control:

• Check SLAM quality and drifts: use quality maps and, if needed, split datasets where drift starts; reprocess with suitable configurations.

• Validate control points and coordinate systems: use the QGIS-based workflow to verify EPSG selection, units, and point IDs against satellite basemaps and quality maps.

Best-practice sequence for complex buildings:

1. Start small: create buildings first, then add one floor at a time; confirm assignments and visibility before proceeding.

2. Model partial/irregular floors as multiple non-overlapping entities; avoid lateral overlaps across levels.

3. After each edit, validate in viewer: toggle floors on/off and confirm POIs and maps display correctly.

Decision helper: when to auto-generate vs. manual

Examples and fixes: step-by-step

A) Floors swapped between Level 1 and Level 2

1. In Site Model Editor, select Level 1, hide other floors, confirm what data displays. Repeat for Level 2.

2. Open dataset assignment dialog, unlink the misplaced bundle from Level 2 and link it to Level 1 (and vice versa). Save.

3. Adjust elevation ranges to ensure no overlap across Level 1 and Level 2. Re-validate by toggling visibility.

B) Partial floor over atrium causing POIs to vanish

1. Split the affected level into two non-overlapping floor entities matching the true extents.

2. If an embedded void exists, use “cut a hole” on the outer building footprint instead of overlapping floors.

3. Re-check POI visibility; move or reassign POIs only after the geometry is correct.

Governance and change control

• Work in small increments; after each change, validate visibility and navigation to catch regressions early.

• Document rationale for outline/elevation changes in the project log to support future audits and handovers.

Related references

• Troubleshooting Control Point Issues Using QGIS