Overlay & Align (4-click)

Partly availableSome of what this page describes is in DimSum today and some is still coming. Parts marked Coming are designed but not built yet.

Show one page on top of another. Click the same two points on each (4 clicks), and DimSum moves, turns and evenly stretches the overlay to fit the main page, so you can see the walls above while you place a beam below.

Overview

Plans for different floors are rarely drawn in the same spot on the sheet, or at quite the same size. To see the floor above while you work on the floor below, DimSum lays one page (the overlay) over the page you're working on (the main page) and lines them up with four clicks.

Alignment is for overlays only. So:

• It's visual. The overlay is moved, turned and stretched or shrunk evenly until it sits on the main page at the main page's size.

• It changes no scale and no quantity on either page. Each page's takeoff is still measured by that page's own scale. There's no scale-mismatch warning and no Match scale.

• Click order: overlay first, then the main page.

• The overlay's paper turns clear and only its linework is tinted, blue at 35% by default.

• Over or under: a setting of the overlay page, On top by default.

• What alignment is for: showing an overlay. 3D, Page Versions, Sync Views and paste don't use it.

Where to find it

• The Project Tree: right-click a page → Show over ‹the page you're on›. That page is shown over the one you have open, and the toast says Page 4 is shown over Page 3. Page ▾ → Overlay… to align or change it. Right-click the page you have open → Overlay….
• Page ▾ in the canvas tool strip, next to Scale ▾, at the end of the page tools: Overlay…, Overlay On / Overlay Off, and Align overlay (4 clicks) (Re-align overlay (4 clicks) once the two are aligned).
• The canvas right-click menu, on an empty spot: the same three.
• Page Properties (nothing selected): an Overlay section for what shows over this page, and an As an overlay section for this page when it's shown over another.

How to use it

Show one page over another

1. Open the page you're working on, the main page, for example Page 3 – Main Floor Plan.
2. In the Project Tree, right-click the page you want to see over it, for example Page 4 – Second Floor Plan → Show over Page 3 – Main Floor Plan. Or Page ▾ → Overlay… and pick it under Overlay page.
3. It shows at once, tinted blue and see-through, on top of the main page. Its paper is clear, so only its linework shows.
4. Until you align it, the overlay sits at the size its own scale says, its top-left corner on the main page's top-left corner. Two sheets drawn at the same scale on the same paper will often be close already. A page with no scale is drawn at the sheet's own size. The Overlay panel says Not aligned — it sits at the size its scale says. Align it with 4 clicks.

A blank page can't be shown over another: it's left out of the Overlay page list, and in the tree Show over … is greyed with A blank page has no plan to show.

Align it with 4 clicks

1. With the overlay showing, Page ▾ → Align overlay (4 clicks). Or the canvas right-click menu, or Align (4 clicks)… in the Overlay panel or Page Properties.
2. Click four points, in this order. The status bar says what each click is for:
3. Click 1 of 4: a point on the overlay, Page 4 – Second Floor Plan (in blue). Esc to stop. Pick a sharp corner on the overlay, such as the front-left exterior corner.
4. Click 2 of 4: the same point on Page 3 – Main Floor Plan. Backspace takes a click back. Click that same corner on the main page.
5. Click 3 of 4: a second point on the overlay, Page 4 – Second Floor Plan, far from the first. Pick a second corner, such as the rear-right corner. The further apart, the truer the fit.
6. Click 4 of 4: the same second point on Page 3 – Main Floor Plan.
7. For clicks 2 and 4 it's hidden, so you see the main page alone.
8. Numbered markers stay where you clicked: the overlay's in its tint, the main page's in the canvas's ink colour. After click 2 the overlay slides so the first pair sits together, which makes the second point easy to find on it.
9. After click 4, DimSum moves, turns and evenly stretches or shrinks the overlay so both pairs of points land together. The toast says what it did, for example Aligned to Page 3 – Main Floor Plan — turned 0.4°, stretched 103%, or … shrunk to 97%. The overlay is switched on for this page.
10. Check the result: stair openings, bearing walls and chases should line up. The alignment is saved with the job. It's one Undo, named Align Page 4 – Second Floor Plan to Page 3 – Main Floor Plan.

While you click:

• Wheel, right-drag, middle-drag and Space+drag pan and zoom between clicks. Panning never counts as a click.
• Backspace takes the last click back.
• Esc throws away an unfinished alignment and keeps the page's old one. Opening another page in the pane does the same.
• Nothing snaps on the overlay clicks (1 and 3). On the main page (2 and 4), snap works as usual and catches your takeoff on that page. It doesn't snap to the plan's own linework yet, so zoom in for a corner on the sheet.
• In the middle of a takeoff run it says Finish the run first (Enter or Esc), then align the overlay.

When the clicks can't make a fit the toast says why, and you go back to click 3 to try the second pair again:

• The same spot twice: Click 1 and click 3 are the same spot on the overlay. Pick two points far apart, like opposite corners of the building. (or Click 2 and click 4 … on the main page).
• Points less than 1% of the sheet apart: Click 1 and click 3 are too close together to line the pages up. Pick two points far apart, like opposite corners of the building. (or clicks 2 and 4).
• A stretch or shrink of more than 20 times: Those clicks would stretch or shrink the overlay more than 20 times. Check that clicks 1 and 2 are the same point, and clicks 3 and 4 are the same point.

Points close together are allowed: two main-page points less than a tenth of the sheet's width apart get the fit, and the toast adds The points were close together, so the turn may be rough. Page Properties says the same afterwards.

See walls above while placing beams

This is the everyday reason to align.

1. Show the Second Floor Plan over the Main Floor Plan and align it (above). You do this once per job.
2. Open the Main Floor Plan, the floor you're framing. Page ▾ → Overlay On (or Overlay Off to hide it). The setting is remembered for that page.
3. The walls above show as a tinted layer on top of your floor, and they stay there while you draw. Draw the beam or joists where the bearing walls above land.
4. The overlay never takes clicks. Every click goes to the main page, so you can always draw takeoff under it. Snap never catches anything on the overlay.
5. Turn the overlay off when you're done. It never changes a quantity, and your takeoff stays on the Main Floor page.

Want the overlay below your takeoff instead? Set its Position to Under the takeoff (below).

Re-align or clear an alignment

• Re-align: Page ▾ → Re-align overlay (4 clicks), or Re-align (4 clicks) in the Overlay panel. The overlay starts where it's aligned now, and the new four clicks replace the old fit, as one Undo.
• Clear: Clear alignment in the Overlay panel or Page Properties, as one Undo named Clear alignment of Page 4 – Second Floor Plan. The overlay goes back to sitting at its own scale, corner on corner. If the two pages aren't aligned, the button is greyed with They aren't aligned.
• The tree shows no ⚠ for an unaligned page.

Overlay a truss or I-joist layout

Coming Import the manufacturer's layout as an Engineered Layout page linked to a level. Show it over the floor or roof plan and align it on two matching bearing corners. See Engineered Layout Overlays.

Options & settings

In the Overlay panel (Page ▾ → Overlay…, titled Overlay on Page 3 – Main Floor Plan) and in Page Properties.

Setting	What it does	Default
Overlay page	The page shown over the one you're on. None, or any other page with a plan	None
Show the overlay	Overlay On/Off for this page. Each pane shows the overlay of the page it has open	On when you pick a page
Tint	Colour of the overlay's linework: Blue, Red, Green, Purple, Orange or Magenta. Its paper turns clear, and its own coloured fills tint faintly too	Blue
Opacity	Slider, 10–90%	35%
Position	On top: above the plan and your takeoff. Under the takeoff: above the plan, but below your takeoff. A setting of the overlay page, so it holds wherever that page is shown	On top

The panel also shows how the two pages line up (Aligned to … — turned …, stretched …%, or Not aligned — …), Align (4 clicks)… or Re-align (4 clicks), Clear alignment, and a reminder: The overlay never takes clicks: you draw on Page 3 – Main Floor Plan under it. It changes no scale and no quantity, and isn't printed.

Page Properties has two sections:

• Overlay: the same controls, for what shows over this page.
• As an overlay: this page's own Position, its own alignment (Aligned to … or Not aligned to another page., plus the turn may be rough note when its points were close), and Clear alignment.

Overlay settings are view state, like zoom: kept with the job, not Undo steps, and not printed. The Position belongs to the overlay page; the page shown, On/Off, tint and opacity belong to the main page. The alignment itself is an Undo step.

and: dropped. Alignment never changes a scale, so there's nothing to check or match.

Not in this build: the plan updater. Comparing a revised sheet with the old one, toggling between them and showing what changed is a separate plan item.

Examples

• Beam under a wall above: on the Main Floor Plan, show the Second Floor Plan over it and align it. The second-floor bearing wall over the living room shows through, and you draw the beam right under it.
• 2-story house with basement: on the Basement plan, show the Main Floor over it and align on two exterior corners, then place the beams under its bearing walls.
• A sheet printed at a slightly different size: the Second Floor sheet came out 1% smaller than the Main Floor sheet. The 4 clicks stretch it to fit (stretched 101%), so the walls line up. Neither page's scale or quantities change.
• Later: a roof truss layout over the roof plan, and Revision 2 of A-101 over Revision 1 (the plan updater and Page Versions).

Tips & shortcuts

• Use two points as far apart as possible, on sharp corners that are on both sheets: exterior building corners, grid-line intersections.
• Nothing snaps on the overlay clicks, so zoom in close for a corner there.
• Backspace takes the last click back, and Esc stops. Wheel zooms, and right-drag, middle-drag or Space+drag pans between clicks.
• Set Position to Under the takeoff when the overlay hides your own lines.
• There's no shortcut for Overlay On/Off yet: Page ▾ or the right-click menu.

Rules, limits & edge cases

• The overlay never takes clicks, and snap never catches anything on it. Every click lands on the main page.
• Alignment never changes a scale or a quantity, on either page.
• The stretch is even. Two points can't fix a page that's distorted (a scan stretched more one way than the other).
• A mirrored (flipped) sheet can't be aligned. There's no flip.
• A page can't be overlaid on itself, and a blank page can't be an overlay.
• The overlay isn't printed.
• Plain takeoff on a single page needs no alignment, and Detail pages never do.

Not yet

• Re-align doesn't show the old clicks again. They're saved in align_pairs_json, but the run starts fresh from where the overlay sits now.
• No shortcut for Overlay On/Off.
• Coming drawing the overlay page's own takeoff in the tint, and snapping to it.

Related features

• Page tools (Rotate, Straighten, Page ▾) · Split views · Page Versions
• Project Tree (Show over …)
• New Project Process (step 7, later)
• Elevation Faces & Face Align
• Beam tool · Engineered Layout Overlays
• 3D viewport