11.9 Annotations
Annotations belong to the 3D view block that carries them, so the tools are on the page bar and appear while one is being framed (§11.4). They are content rather than view state: each one commits as you place it, and undoes normally, without waiting for Update. A sheet that is merely being arranged draws none of them — there is no frame to lay anything out in — and the venue’s own rulers stand down for the duration, so a printed drawing carries what was laid out on it and nothing left lying around the scene.
| Tool | What it does |
|---|---|
| Measure | Two points, vertex-snapped. X/Y/Z lock to an axis; hold Alt to suppress snapping. |
| Angle | Three clicks: an arm, the corner, then the other arm. Tab swaps the inner angle for the outer one. |
| Callout | Click a point and type. Enter commits, Shift+Enter makes a new line. |
| Pin | A live lux / px-per-m readout anchored to a surface. |
| Labels | Projector, device and rack name callouts. |
All of them anchor to any visible body — surfaces, models, projector chassis, devices and cable trays. You can dimension a projector to the tray above it, or a rack to the truss over it.
Click one and its two ends become grips; drag one and that end is taken again from wherever you drop it — the same snapping to vertices and to a projector’s lens, and the same X/Y/Z locks, now running through the other end. Esc mid-drag puts it back; a finished drag is one Ctrl+Z. It is not a translation — the end lands on what is under the cursor, which is what a measurement is: two places in the venue.
The grips are there only while it is selected. Left alone, a measurement takes no clicks on its ends at all, so a ruler lying across a venue never comes between you and the corner it is measuring to.
A dimension measured on a sketch (§3.11) never grows these grips: its ends belong to the drawing, and you drag them inside the sketch editor, where they snap to its corners and its grid. Open the drawing to move one.
Angles
A takes the angle tool — the ruler's sibling, and the only annotation that wants three clicks: an arm, the corner, then the other arm, so the middle click is the one that lands on the corner. It snaps exactly as the ruler does, reads out live from the second click, and stays armed so the next one is three more clicks.
Tab swaps the inner angle for the outer one — while you are placing it, and afterwards on one you have selected. Three points describe two angles that add to 360°, and which of them you meant is a fact about the question rather than about the points: a splayed wall read from inside the room and from the corridor outside it is the same three clicks and two different answers. So the answer is stored with the measurement, and an angle you never pressed Tab on reads the inner one.
The arc is the part that says which angle is meant, and it is also the part you click to select one — the arms are left alone deliberately, since they run along the very geometry you are measuring and a fat target there would sit between you and it. Selected, an angle offers three grips: both arms and the corner, dragged like a ruler's ends.
Angles work wherever the ruler does — in the venue, on a report page, and inside the sketch editor, where A arms it against the drawing's own corners and grid.
Measuring a projector’s throw
Two refinements make this work on a machine that is actually aimed somewhere:
- Hovering a projector adds its lens — the point the optics throw from, and the one the Metrics Throw reads — as a snap candidate. Without it, “lens to wall” came out as whichever chassis corner you happened to grab.
- Pressing an axis key a second time swaps that axis from world to the anchor object’s own frame. So Z Z runs the far end down the projector’s optical axis. A third press clears the lock.
Once a projector is aimed off-square, no world axis is parallel to its throw — so a world lock measures a projection of the throw rather than the throw. A unit rolled 30° off vertical at 4 m reports 4.000 m under a world lock, and 4.619 m under its own.
While an axis is locked, the point where that axis pierces the scene is itself a snap candidate, so the far end can land on the wall instead of sliding through it.
Pins recompute
A pin stores only geometry — a point, the normal of the face it sits on, and which body it belongs to. Every number it shows is recomputed, so a pin stays true as the rig changes around it. On a sheet it shows the readings taken with the block’s picture, through that view’s own hidden set; they are refreshed with the picture and dropped with it.
Ink follows the picture underneath
An annotation over a view block always lands on the render, which fills the block edge to edge, so there are two palettes and the block’s render mode picks one. Over a shaded view: white ink, dark chips, and the viewport’s own axis colours, so a ruler locked to Y is green in the venue, green on the sheet and green on paper. Over a drawing (§11.5): black ink, white chips ruled in black, and darker axis colours that survive white paper.
That is the whole answer to “why does the report look different from the viewport”: it should not, and the layout, the colours and the arcs are computed once and drawn by the viewport, the sheet and the PDF alike.