9.1 A tray is a network

A tray object stores points and the stretches between them; every stretch draws with the network’s width and side-rail height. A corner is two stretches sharing a point, and a tee is a point where three meet — geometry inside one object, not separate objects lined up. + Object ▸ Cable tray drops a single 3 m stretch overhead; everything after that is shaped from its points.

The rule

One object is one connected network. An edit that brings two trays into contact fuses them into one object; deleting the stretch that bridged a network splits it back into one object per piece, and any routed cable follows the piece nearest its ends. The object list always mirrors what is physically connected — there is no link to create and nothing to go stale after an undo. Either way it is a single undo step.

Top view of a cable tray network, with grey dots on its free ends — Figure 9.1 The demo project’s run, seen from directly above in orthographic view (`O`) — the way a tray run reads best. **Grey** dots mark free ends; a plain bend carries no dot, and a junction — three or more ways meeting at one point — shows **green**. The orange and blue lines running inside the channel are cables routed through the network, dropping off where each reaches its projector.

The dots and the drag handles go away with the tray: hide a run — with its own eye, with an ancestor’s, or with a report page’s per-view hide (§11.4) — and its graphics go too, rather than hanging in front of the venue over a run that is no longer drawn.