Joins and the green / yellow / red signal
Every place two connectors meet, the planner records a join. Each join is classified by how good the fit is:
| Colour | Gap | Angular error | Meaning |
|---|---|---|---|
| Green | ≤ 0.001 mm | ≤ 0.001° | Perfect mate. Behaves exactly like factory geometry. |
| Yellow | ≤ 2 mm | ≤ 1° | Strained join. The track will hold but you'll feel it — slight bend in the rail, audible click as a long wheelbase passes. |
| Red | > 2 mm or > 1° | — | The join won't physically close without forcing geometry that the catalogue doesn't support. You need a different piece, a flex section, or to rework that part of the plan. |
Why we don't just warp pieces to fit
A lot of planners silently bend track geometry to close almost-closed loops. We don't. The whole value proposition of Locodex is "what's on the screen is what builds." If we warped a piece, the spline you see in 2D wouldn't match the piece you'd actually buy — you'd discover the mismatch with track in your hand, which is the worst possible time.
So instead the planner shows you the strain directly. A yellow join is a real, build-acceptable join with a real, measured gap. A red join is honest about not fitting.
The "almost closes" case
A common situation: you've laid a loop and it almost closes, off by maybe a millimetre and half a degree. You can:
- Accept the yellow. Build it; the rail flexes that much without complaint.
- Adjust the geometry. Add an eighth-curve, swap a straight, or move a turnout one piece up. The planner will reclassify the join on every change.
- Use a flex section (when flex track ships). Flex absorbs small misfits cleanly.
Inspecting a specific join
Click the dot at a join (or the piece next to it) and the inspector on the right shows the join's metrics — gap in millimetres, angular error in degrees, and the connector types on each side.