Trusses and Mounting

Trusses, bases and the mounting workflow let you build the physical rigging plot alongside the projection design. Projectors and LED tiles attach to a truss by clamp position and hang direction; deleting or moving the truss carries everything mounted on it.

Object types

Truss — a rigging member with a procedural chord-polyline geometry. Seven shapes are supported: Tower, Horizontal Span, Goal Post, A-Frame, Ladder, Arc, Ring. Each truss owns a chord profile (e.g. Square 12” Truss) drawn from the catalogue.
Base — a procedural box that sits under a Tower / Goal Post / A-Frame, or stands alone as a load-spreader. Sizes are driven by a footprint in mm.

Trusses and bases live in the Scene panel as first-class objects with their own type-dot colour.

Add a truss or base

Click Mounting in the viewport toolbar’s add cluster to open the popover. Pick one of:

A truss type (Truss Tower, Horizontal Span, Goal Post, A-Frame, Ladder, Arc Truss, Ring Truss) — Tower, Goal Post and A-Frame instantiate with their default base attached; the others stand alone.
A base (Base Plate, GB Block, Sled, Outrigger) — adds a standalone base mesh.
Truss library… — opens the full catalogue with cross-section filters and the option to instance a saved custom truss.

Mounting popover in the viewport toolbar

Truss properties

Click the truss in the viewport, or pick it from the Scene panel, and the sidebar shows:

Type — switch between the seven truss shapes; geometry rebuilds in place.
Profile — the chord cross-section (Square 12”, Square 20”, etc.). Drawn from the truss product catalogue.
Length / Span / Diameter / Apex height — dimension fields specific to the type. Goal Post exposes both leg and span lengths; Arc and Ring expose radius and arc angle.
Base — when present, links to the Base child the Tower / Goal Post / A-Frame was created with. A Base sidebar appears once you select it.

Custom trusses and bases

The truss library overlay’s + Create custom button opens the same form pattern used for projectors. Set the truss shape, chord profile, span and weight; for bases, set the footprint and mass. Saved custom rows appear under “Project copies” in the library and instance like catalogue rows. Catalogue rows are read-only.

Mount a projector or LED tile

Select a projector or LED tile and expand the Mounting collapsible in its Properties panel.

Show cage — toggles the visual cage / yoke around the projector body. Cage visibility is independent of mounting; you can have a cage in free space, or a mounted projector without one.
Clamp pickups — the points on the projector body that hang on a truss chord. Most catalogue projectors ship with their factory pickup positions baked in; Edit… opens the Clamp Pickup editor to add per-instance overrides. Reset drops the override and falls back to the catalogue default.
Mounted to — choose between Nothing (free transform) and Truss (clamped to a truss centreline).

When mounting is set to Truss but no truss is picked yet, three quick-action buttons appear:

Ground tower — spawns a fresh Truss Tower, parents the projector to it, drops it onto the floor.
Flown truss — spawns a Horizontal Span at the projector’s current height and parents the projector to it.
Existing truss — dropdown listing every Truss already in the scene.

Once mounted, the sidebar surfaces the truss-relative pose:

Clamp position — the parameter t along the truss centreline (0 = start, 1 = end). Drag the slider to slide the projector along the chord.
Hang from — Below chord, Above chord, Side of chord (left), Side of chord (right). Switches which face of the chord the projector clamps to.
Height offset — distance from the clamp face along the hang direction, in mm. Useful for chain-motor drops below a flown truss, or stand-off plates on the side of a tower.
Unmount — returns the projector to free transform, leaving its current world pose intact.

The same Mounting block appears on the LED-tile sidebar with the same fields.

Cage

Toggling Show cage draws the projector’s yoke / cage rig over the body — independent of mounting, so a free-standing projector can carry a cage too. When the projector is on a truss, the cage moves with the body as you slide the clamp position.

Mounting arrays

Mounting a Symmetry-wrapped projector carries the whole array onto the truss — every copy stays in lockstep. Edit the clamp position once and every projector in the array follows.

Grouped undo

Mounting is a multi-step operation (reparent, set clamp, set offset). Mapping Matter wraps it in an undo group so a single Ctrl+Z reverts the entire flow rather than peeling it back one signal at a time.

Snap to truss on drag

Drag an unmounted projector close to a truss and Mapping Matter prompts:

Snap — clamp it to the nearest centreline point and switch the projector into mounted mode.
Always snap this session — same as Snap, plus suppresses the prompt for subsequent near-truss drags for the rest of the session.
Don’t snap — leaves the projector where you dropped it.

The “Mount on nearest truss” action in the Mounting toolbar popover applies the same nearest-centreline logic without needing a drag.

Collision warnings

Trusses get a continuous spatial-collision check against scene meshes (Reference imports, Primitives). If a truss intersects geometry, its outline pulses red. Move the truss or resize the geometry to clear the warning.

The collision outline is purely a guidance overlay — it does not block the placement.

The Clash button in the viewport toolbar’s display cluster toggles these warnings on and off — useful when you want to position a truss inside a structural column on purpose without the red pulse drawing attention away from the rest of the scene. The setting is per-scene and saved with the project.

Delete with attachees

Deleting a truss that has projectors or LEDs mounted to it opens a 3-way prompt:

Delete attachees too — removes the truss and everything mounted on it.
Unmount and keep — deletes the truss only; the attachees revert to their last truss-relative pose in world space.
Cancel — closes the prompt without changing anything.

Truss BOM CSV

The toolbar’s Export menu includes Truss BOM as CSV — a rigging bill of materials (BOM). The file rolls up:

One row per truss (type, profile, dimensions, mass).
One row per base (product, footprint, mass).
Per-truss attachees rolled up — projectors and LED tiles walked through any Symmetry copies so the count reflects what’s actually rigged.

Use the BOM as a handoff artefact for the rigger or to sanity-check loading totals before sign-off.