Cella User Guide

Cella opens PDF drawing sets the way architects and contractors use them, lets you mark them up, measure them and hand them on as ordinary PDFs that Acrobat and Bluebeam Revu read. Nothing leaves your computer unless your office shares its drawings through an Atrium server.

This guide describes Cella 1.0 on the Mac. Keys are given for the Mac first, with the Windows and Linux keys beside them in brackets; where a key has none beside it, Ctrl stands for ⌘ and Alt for ⌥ on those systems (see Keyboard shortcuts). Every picture is of the same sheet, A-101 First Floor Plan of a small clinic, part-way through a review by four people.

#Welcome and editions

When Cella starts without a document it shows the Welcome window. Open PDF… (⌘O) and Open Folder as Set… (⇧⌘O) are on the left, with a place to drop a PDF or a folder. On the right, Recent shows the documents and sets you have had open as cards: a picture of the first sheet, the folder it is in, and the sheet and markup counts from the last time you had it open. Click a card to open it; right-click it for Show in Finder (Show in Explorer, Show in Files) and Remove from Recents. A file that has been moved or deleted is greyed out as "Not found". Join a sync server…, the User Guide (this guide) and the Release Notes are at the bottom.

The Welcome window closes as soon as a document opens. Bring it back with Window ▸ Welcome (⇧⌘1; Ctrl+Shift+1). Untick Show this window when Cella opens to go straight to the Open dialog instead.

In a beta build the Welcome window also has a Beta card above Recent, with the beta guide, Report a Bug… and what's new in 1.0; tick Don't show again to hide it. Until you have opened it, a Try the sample set card offers Open the sample drawing (the clinic floor plan used for the pictures in this guide) and Open the sample set (a folder of three sheets, A-101 to A-103). Each puts a copy in Documents/Cella Samples and opens it, and never overwrites a copy you already have.

#One product, one key

Cella is one product, the same download for everyone: $149 once, with every 1.x update. One key covers one computer (Mac, Windows or Linux) and one iPad; the iPad app is coming, and until it is a key simply covers one computer.

A 14-day free trial starts by itself the first time you open Cella on a computer, with no sign-up and no payment details, and everything works. The toolbar (status bar on Windows and Linux) counts the days left, and so do About (Free trial · N days left) and the license window. The trial runs once per computer.

When the trial ends without a key, Cella is view-only (About says Trial ended · view only). What stays open to everyone, key or not:

In view-only Cella the markup and measuring tools, the style strip and Undo / Redo are not on the toolbar, and the commands that change a document are greyed out with a tooltip saying a license is needed. If you try one anyway, Cella says: "Your 14-day free trial has ended. Buy Cella or enter a license key to keep marking up." Your drawings and markups stay open and readable, nothing is lost, and markups you haven't saved can still be discarded when you close the window.

#Buying, entering a key and deactivating

The license commands are under Cella ▸ Cella License… on the Mac and Help ▸ Cella License… on Windows and Linux; the Buy Cella… button on the toolbar opens the same window.

• Buy Cella… opens the checkout in your browser; the license key arrives by email.
• Enter License Key…: paste the key (spaces and line breaks from the email don't matter) and click Activate. The computer appears under its own name in your key's list of devices, and About reads Licensed to your name. A key for another product is refused.
• Deactivate This Device… frees this computer's place on the key, for a new computer (or, when the iPad app arrives, to move the key's one iPad place). Do it before you replace or wipe a computer. If the license server can't be reached, the license stays until you try again online.
• Cella checks the license with the store at most once a day. Offline, a licensed Cella keeps working for 30 days since the last successful check; after that it is view-only until Check Again in the license window gets through. A refunded or disabled key switches to view-only at the next check, with a message.

The key is kept in the Keychain on the Mac, encrypted for your Windows account on Windows, and in your desktop's keyring on Linux. Checking it sends Lemon Squeezy, the store that sells Cella, the key and the computer's name, nothing else.

#Windows and Linux

The Windows and Linux versions have the same menus and panels as the Mac and nearly all of its features, built over the same document layer, with the keys listed under Keyboard shortcuts. Where they differ it is said in the section, and the last section of this guide lists what they are still missing. They have been built and tested automatically but not yet used on those systems; tell us what you find.

#Getting started

#Opening a sheet or a set

• File ▸ Open… (⌘O) opens one or more PDFs. They open as tabs of the front window (see Tabs).
• File ▸ Open Folder as Set… (⇧⌘O) opens a folder of PDFs as a set: every PDF in the folder and one level of subfolders, sorted the way people sort sheet numbers (A-101 before A-1001). The sidebar opens on its Set tab, which lists the files with their markup counts; click one to open it in the same window. More under Folder sets.
• File ▸ Open Recent lists the files you opened lately; the Welcome window shows them as cards.
• You can also drop PDFs and folders on the Welcome window, or PDFs on Cella's Dock icon.

Cella reopens the documents you had open when you quit (Settings ▸ Reopen documents at launch).

#The window

• Toolbar, left to right: Select and Pan; the markup tools; the measuring tools; the Tool Chest; Undo and Redo; zoom out, the zoom percentage (click it for presets), zoom in and Fit Page; then the pop-out button for the tool palette and the three panel buttons (Sheets, Markups List, Properties). Open, Save and Print are in the File menu.
• Options row, under the toolbar while a drawing tool is picked or markups are selected: the colours, fill, line width, opacity and whatever else that tool uses (line ends, cloud, and for text the font, size, bold, italic and alignment).
• The drawing fills the middle. The side panels run the window's full height, so the toolbar, the options row, the sheets strip and the status band are as wide as the drawing.
• Properties, at the right (⌥⌘P; Ctrl+Alt+P), shows the selected markup, or the defaults of the tool you have picked when nothing is selected.
• Markups List, under Properties (⌥⌘M; Ctrl+Alt+M), lists every markup in the document. See The Markups List. Drag the line between Properties and the list to share the column between them. Properties' Style, Position, Organise and People headings fold away with a click, and empty Layer, Space, Label and reply rows stay out of the way until you click "empty" beside the heading. Settings ▸ Panel rows ▸ Compact packs the rows closer, and Settings ▸ Right column puts the Markups List on top. On a large monitor, View ▸ Detach Properties and Detach Markups List float each in a panel of its own; Reattach (or the panel's close button) puts it back.
• Sheets strip, along the bottom: see below.
• Status band, along the very bottom: Sheet 1 of 1, the sheet's name and scale (click the scale to set it), the sync state and how many markups are selected, then the zoom, the moon for Invert Drawing and ? for the keyboard shortcuts.

The hot colours in the options row (magenta, orange, lime, cyan, violet, yellow, red, blue and ink) are for marking up quickly: click one for the stroke, Option-click (Alt-click) for the fill. The Colour… well next to them takes any other colour.

When the window is too narrow for every tool, the ones that don't fit move to a ⋯ menu after the tool groups; their keys still work, and Properties always has the full set of controls. Below 1280 points wide the sidebar and the right-hand column float over the drawing instead of squeezing it; the pin at the top right of a panel docks it beside the drawing (or floats it) until you quit, and View ▸ Panels Overlay the Drawing chooses Automatic, Always or Never.

View ▸ Tool Palette (⌥⌘T; Ctrl+Shift+T), or the pop-out button, floats the tools and the style strip in a small window of their own that you can park beside the drawing; close it to dock them back.

#The sheets strip and the sidebar

Sheets run as a strip of thumbnails under the drawing (View ▸ Sheets at Bottom, the default), where a landscape drawing has room to spare. The pill on a thumbnail is its markup count; the sheet on screen is ringed. Click a thumbnail, or click the strip and use ← and → (Home and End for the first and last). View ▸ Show Sheets (⌥⌘S; Ctrl+Alt+S) hides and shows it. Drag the strip's top edge to make the thumbnails bigger or smaller (double-click it for the usual size), or click the strip and press ⌘+ or ⌘−; View ▸ Sheets ▸ Larger Thumbnails and Smaller Thumbnails do the same, and with the sheets at the left they switch the list between small, medium and large thumbnails.

The sidebar at the left opens when you need it: for searching (⌘F) and when a folder set opens. Its tabs are Sheets, Set (with a folder set open) and Bookmarks (when the PDF has bookmarks). Close it with the × in its heading. View ▸ Sheets at Left keeps the sheets in the sidebar instead of the strip, with a filter field above them.

#Zoom and navigation

• Zoom with ⌘+ and ⌘−, a pinch, or ⌘ and the scroll wheel (Ctrl). View ▸ Fit Page ⌘0, Fit Width ⌘1, Actual Size ⌘2; the fit button beside the zoom in the status band (or a click on the zoom itself) always brings the whole sheet back, Option-click fits the width, and Home puts the sheet's top-left corner back in view at the same zoom.
• Pan with Space held down while you drag, the middle mouse button, the Pan tool (⇧V), or the scroll wheel and trackpad.
• Sheets: ⌘↓ and ⌘↑ (Ctrl+Down, Ctrl+Up) or Page Down and Page Up for the next and previous sheet; ⌥⌘↑ and ⌥⌘↓ (Ctrl+Home, Ctrl+End) for the first and last. Zoom and position stay put when you change sheet.
• View ▸ Go to Sheet… (⌥⌘G; Ctrl+Alt+G, or ⌘G when nothing is being searched) takes a sheet number or a sheet name such as A-101.
• With the Select tool, click a sheet reference in the drawing ("12/A-512", "SEE A-301") to go there (see Links).

#The command palette

Help ▸ Command Palette… (⌘K; Ctrl+K) finds any command by typing a few of its letters: "fw" finds Fit Width, "rot" Rotate Right. Each result shows where it lives in the menus and its shortcut; ↑ and ↓ choose, Return runs it, Esc closes. Start with > to jump to a sheet (with its thumbnail), @ for tools, Tool Chest tools and stamps, and # to find a markup by its subject or comment and select it. The commands you ran lately come first.

#Dark mode and Invert Drawing

Cella follows the system's light or dark appearance; Settings ▸ Appearance chooses System, Light or Dark for Cella alone. In dark mode the panels go dark and the sheet stays paper-white, so colours read as they will print.

For night work, View ▸ Invert Drawing (⌃⌘I; Ctrl+Alt+I), or the moon in the status band, shows the sheets white on near-black. Your markups keep their real colours, a red line in the drawing stays red, and printing, exporting and the thumbnails are unchanged. Cella remembers it.

#Tabs

Documents open as tabs of the front window (Settings ▸ Open documents in tabs turns this off). On the Mac, ⌥⌘← and ⌥⌘→ (Window ▸ Show Previous Tab / Show Next Tab) move between tabs; drag a tab out for its own window, or use Window ▸ Move Tab to New Window, and Window ▸ Merge All Windows to gather them again. The + at the end of the tab bar opens a PDF in a new tab. Each tab keeps its own sheet, zoom, panels and selection.

On Windows and Linux a tab strip appears under the toolbar once a window holds two documents. Ctrl+Page Up and Ctrl+Page Down move between tabs, Alt+1 to Alt+9 jump to one, a middle click or the tab's × closes it, and Window ▸ Move Tab to New Window gives a tab its own window.

#Split View

View ▸ Split View (⌘\; Ctrl+\) shows the document twice, side by side (Vertical) or stacked (Horizontal), each pane with its own sheet and zoom: a plan beside its detail. Drag the line between them to resize; double-click it for half and half. ⌘\ again closes the split; the first pane stays.

• Markups you draw or change in either pane appear in the other straight away; you save as usual (⌘S).
• The pane you are working in has a blue outline, and the Markups List, Properties and the sheets strip follow it.
• The link button in the status band (Sync Pan and Zoom) keeps both panes at the same zoom and centre; the two panes button next to it (Sync Sheets) also follows sheet changes.
• Split View ▸ Nudge Second Pane Left / Right / Up / Down moves the second pane's drawing a little, for two issues plotted slightly apart; click the offset in the status band (or Reset Offset) to put it back.
• Open Another File in Second Pane… shows a different PDF there, read-only, for looking at two issues side by side. Show This Document in Second Pane goes back.

Each window or tab has its own split.

#Reading a set

#Sheets and sheet numbers

Cella reads each sheet's number from its title block, so the strip, the sidebar and the status band say A-101 rather than "page 1". A PDF that carries sheet names (page labels) shows those.

• Rename a sheet: double-click its row in the Sheets list, press Return on it, or right-click ▸ Rename Sheet…; type the name and press Return (Esc cancels; an empty name goes back to "Sheet N").
• Tools ▸ Detect Sheet Numbers… renames every sheet to the number in its title block, replacing the names the file had and your own.
• Tools ▸ Sheet Index… reads the drawing list off the cover sheet; see Sheet index.

Saving writes the names into the PDF as page labels, so Acrobat and Bluebeam show the same names.

#Bookmarks

When the PDF has bookmarks, a Bookmarks tab appears in the sidebar. They are listed nested as the file has them (click a triangle to open or close a group); click one, or arrow through them, to go to its sheet, zoomed to the place it marks.

You can edit them:

• Sheets ▸ Add Bookmark, or + at the top of the Bookmarks tab, marks the sheet and the view on screen; type its name straight away. ↳ adds it inside the selected bookmark.
• Double-click a bookmark to rename it; Delete (or −) removes it; drag bookmarks to reorder them, or onto another to nest them.
• Markups ▸ Bookmark This Markup (also on a markup's right-click menu) marks a markup, zoomed to it. Sheets ▸ Bookmarks from Sheet Labels… makes one bookmark per sheet, named like the sheet.
• Save writes the bookmarks into the PDF, where Acrobat, Revu and Preview show them too. ⌘Z undoes bookmark changes one at a time, with your markup edits. Bookmarks follow their sheets when you move or insert sheets.

#Search

Edit ▸ Find… (⌘F; Ctrl+F) puts the cursor in the sidebar's search field. Type and press Return to search the drawings' text and the markups (subjects, comments, replies, custom columns and stamp text). The results replace the sheet list, grouped by sheet with their counts and the match in bold; the field shows "2 of 16".

• ↑ and ↓ move through the hits; Return jumps to one (again: to the next).
• Edit ▸ Find Next ⌘G and Find Previous ⇧⌘G (Ctrl+G and Ctrl+Shift+G, or F3 and Shift+F3) step through them from anywhere. Esc clears the search.
• The toggles under the field: Aa Match Case; W Whole Word ("22" finds DETAIL 22/M-152 but not M-222); .* Regular Expression (A-5\d\d, RFI\s*12; a pattern with a mistake says so); and the speech bubble, which includes the markups.
• With a folder set open, Whole Set searches every file (the same choice as the Markups List's This File / Whole Set). Results are grouped by file; choosing a hit in another file opens it there. Cella keeps what it read of each file in .cella/text-index/ beside the files, so a second search of a big set takes a moment instead of reading every PDF again.
• Replace…, under the field, changes the matching text in this file's markups (subjects, comments and replies: "ASI 4" to "ASI 7") after telling you how many it will change. One Undo puts it all back.

Visual Search finds a symbol by how it looks, not by its text. Choose Visual above the toggles (Markups searches only the markups' text), click Pick Symbol… and drag a box around one door swing, receptacle or fixture tag on the sheet: Cella lists every other place it is drawn, grouped by sheet like text hits, and outlines them on the sheet. All Sheets looks on every sheet of the document; Rotations also finds it turned 90°, 180° or 270°; Size ±10 % finds it a little smaller or larger; the Match threshold slider (60–95 %) says how alike a place must be. Place Counts then puts a Count markup on every symbol found, with the Count tool's symbol, ready for the take-off, and Mark for Redaction covers each one with a redaction mark; one Undo takes either back.

Scanned sheets are pictures with no text, so there is nothing to find on them until you choose Document ▸ Recognize Text (OCR)…: pick the sheets without text, this sheet or all of them, and Cella reads the words on your computer (nothing is sent anywhere). Search, Find Next, Whole Set, selecting and copying text, highlighting it, Mark Search Results for Redaction and Detect Sheet Numbers then work on those sheets. The words are kept in the .cella folder beside the file and the PDF is left as it was, unless you tick Also write an invisible text layer into the file so other apps can search it too. Settings ▸ Recognise text on scanned sheets automatically reads a scanned title block for its sheet number when a set opens. The Mac reads with its own text recognition and Windows with Windows' own (it uses the OCR languages installed with Windows); on Linux, install Tesseract (for example sudo apt install tesseract-ocr): Cella doesn't bundle it.

To check what was read, choose View ▸ Show Recognized Text: every word Cella found gets a thin box on the sheet, with the word in a small label when you point at it. Words the Mac's recognition was unsure of are boxed in amber (Windows doesn't say how sure it is), and words you corrected in green. Double-click or right-click a word to fix it: type the right word and press Return, press Esc to leave it, or press Delete to remove a word that isn't one (a smudge read as text). Search and selection use your correction at once, Undo takes it back, and it is kept beside the file with the rest of the words. When you recognize the text again, Keep my corrections (on by default) keeps each corrected word that is found again in the same place. If you wrote the invisible text layer into the file, the file keeps the earlier words until you run Recognize Text again with that box ticked.

#Selecting and copying the drawing's text

With the Select tool, drag across the drawing's own text (the pointer becomes an I-beam over it) to select it, as in Preview. The selection follows reading order across lines, and down a notes column rather than across the plan beside it. Double-click selects a word (a sheet reference such as 12/A-512 counts as one), triple-click a line, Shift-click extends. ⌘C copies it; Esc or a click elsewhere clears it.

Right-click the selection (or use the Edit menu) to Search for it, or to Highlight, Underline or Strikeout it, or Mark Text for Redaction. The rule that lets one Select tool do both jobs: a drag that starts on a markup moves the markup, one that starts on text selects text, and one that starts on empty paper draws a marquee that selects markups.

#Layers

View ▸ Layers lists the PDF's own layers (what the CAD export put on layers) and the layers markups use; untick one to hide it. View ▸ Show Markups hides every markup at once, to see the bare drawing.

#Links

Links take whoever clicks them somewhere: another sheet, a detail at a zoom, a web page or another file. With the Select tool a click follows a link (also when the trial has ended); the status band says where a link goes while the pointer is over it. View ▸ Show Links outlines every link on the sheet.

Tools ▸ Link Sheet References… turns every sheet number in the drawings' text into a link to that sheet, across the files of a set. Running it again replaces the links it made before, but not ones you have edited.

Making your own links:

• Tools ▸ Link (K): drag a rectangle over what should be clickable, then choose what it does: - Go to a sheet: fitting the whole sheet, keeping the zoom, or showing a region (Choose Region… takes you to that sheet to drag the region, then back). - Go to a snapshot view: Choose View… takes you to the sheet; pan and zoom to the view and click Use This View (or press Return). - Open a web address, or Open a file (another PDF, and the page to open it at). - A border (none, underline or box) and its colour.
• Markups ▸ Add Link to Markup… (or the markup's right-click menu) puts a link on a markup, and it moves with the markup. ⌘-click the markup to follow it; a plain click still selects it, and a ⌘-drag moves it free of snapping without following the link.
• To change or remove a link, pick it with the Link tool (or right-click it). Properties shows where it goes, its border and colour, with Edit Link…, Follow and Remove. Drag it with the Link tool to move it; Delete removes it.

Links are standard PDF links: Acrobat, Revu and Preview follow them. Rotating, moving, inserting and deleting sheets keeps every link on its sheet and pointing at the right one.

#Spaces

Spaces are named areas of a sheet (rooms, zones, units), as in Revu. Every markup drawn or moved inside a space takes its name in the Space column of the Markups List, so you can count and total by room.

• Tools ▸ Space (⇧S): click the corners of the room, double-click (or press Return) to close it, and name it. The tool stays on for the next room.
• While the Space tool is on, Properties lists the sheet's spaces: type over a name to rename it; the bin deletes it; Copy to All Sheets (also Tools ▸ Copy Spaces to All Sheets) puts the same spaces on every other sheet, for floors that share a plan.
• Tools ▸ Create Spaces from Rooms… finds the rooms for you, the way Dynamic Fill does: every area the walls close (doors narrower than the Fill gap count as closed) of at least 20 sq ft becomes a proposed space, named after the text inside it ("OFFICE" with "201" under it becomes OFFICE 201; a room without text is Room 1, Room 2…). Choose This Sheet or All Sheets, untick what you don't want (a title block's boxes, say), rename any, and click Create. A room that already has a space is listed as "already a Space" and left unticked. Markups inside take the names at once, and one Edit ▸ Undo takes all the new spaces away.
• View ▸ Show Spaces shows them as faint tinted areas with their names. Other PDF viewers never show or print them.
• A markup takes the space its middle is in (the smallest one, where spaces overlap). To choose one yourself, pick it or type it in Properties ▸ Space; the markup then keeps that name wherever it moves. Clear the field to let its position decide again.
• Markups List ⋯ ▸ By Space groups the list (and the CSV) by space, with totals; Markups ▸ Insert Legend… can group by space too.

#Compare

Cella has two ways to see what changed between two issues of a sheet.

View ▸ Compare With… (⇧⌘K; Ctrl+Shift+K) overlays another issue on the sheet on screen: the linework both share dark, this issue red, the other blue. Step through the sheets with View ▸ Compare: Previous Sheet / Compare: Next Sheet, and Stop Comparing when you are done. The status band says what you are comparing with.

View ▸ Compare Documents… finds what changed and clouds it. Pick the other issue, then choose:

• Sheets: This Sheet, or All Matching Sheets (paired by sheet number when both are sets, else page by page).
• This document is: The Newer Issue or The Older Issue (whether a change reads "added" or "removed").
• Sensitivity (Low, Medium, High), Smallest change (on Windows "Ignore changes under"; 1, 3, 6 or 12 pt) and the Cloud colour; untick Cloud the changes just to count them.

Cella lines the sheets up (small plot offsets are absorbed), draws a cloud round each change on the layer Compare, commented "added", "removed" or "changed", and filters the Markups List to them. Edit ▸ Undo takes the whole run back; Markups ▸ Remove Compare Clouds clears them later. Use Compare With… to look closer at one. File ▸ Set ▸ Compare Set with Folder… does the same for every file of a set; see Folder sets.

File ▸ Set ▸ Compare Sets… compares a whole issue with the previous one. Open the new issue as a folder set (or open it as one multi-sheet PDF), choose the previous issue's folder (or PDF), and Cella pairs the sheets by sheet number, whatever the files are called: the number in the title block or the page label, else the file name. Each pair is compared as above (Resolution and Plot offset trade speed for finer changes and larger re-plot shifts), the changes are clouded on layer Compare and each sheet's count is reported, with the sheets new in this issue and the ones removed. Tick Save a Compare Report for a PDF listing every pair with its counts and a picture of each clouded region. The other files of the set are saved with their clouds; the open file's clouds are one Edit ▸ Undo step. Cancel while it compares leaves every file exactly as it was.

#Overlay pages

View ▸ Overlay Pages… draws two to four sheets on top of each other, each in its own colour, so you can see at a glance what moved between two issues, or where the structure clashes with the architecture. Ink that only one sheet has keeps that sheet's colour (blue for the first, red for the second, then green and magenta); where the sheets agree, the colours multiply to black.

1. Choose the sheets. Each row is a sheet of this document or, with Choose File…, of another PDF; click the colour well to change its colour. Add Sheet adds a third and fourth; − removes one. To overlay two sheets of this document you can also select them in the Sheets list and right-click ▸ Overlay These Sheets.
2. Choose the alignment. Automatic finds the offset between the sheets (a plot shifted by up to about two thirds of an inch). None lays the top-left corners together. Pick Points… shows the sheets side by side: click the same two or three points on each, in the same order (grid intersections or column corners far apart work best). Two points move, turn and scale the sheets to match; three also correct a skew.
3. Choose the output. Insert as New Sheet adds the overlay right after the first sheet, named "Overlay of A-101 and A-101 (rev 2)" (Edit ▸ Undo takes it out again); Save as PDF… writes it as a one-page PDF and leaves the document as it was.
4. Check the preview and click Overlay.

The overlay is a picture of the sheets (150 dpi) without their markups: it is for looking, not measuring. Compare Documents… is the tool that finds and clouds the changes.

#Marking up

Marking up needs a key or the trial. Pick a tool from the toolbar, the Tools menu or the tool palette, or press its key while the drawing has the keyboard. A tool goes back to Select after one markup; Shift-click a tool (or press its key twice) to keep it. Esc goes back to Select, or cancels the markup you are drawing.

#The tools

Edit Text (⇧T; Shift+T) changes the drawing's own text, not a markup: click a line of it, a field opens there with its words, type, and press Return (Esc leaves it as it was). The sheet's text is rewritten where it is, in the same font, size, colour and place; letters you keep don't move, and longer text runs on to the right. Click a line of a paragraph (a note of several lines in one font and size, lined up on the left and evenly spaced) and the whole paragraph opens in one box: when you press Return it is broken into lines again at its own width and line spacing, with lines added below or taken away as the text needs. The rest of the sheet doesn't move, so a paragraph that grows runs down over whatever is under it; check it, and Undo if it collides. Text inside a block is edited too when the block is placed once; a block placed several times (a detail tag, a door number used everywhere) is refused with how many times it is placed, since changing it would change every copy. CAD files often embed only the letters they use: type a letter the drawing's font doesn't have (an "É" in a sheet that never had one) and Cella writes the line with Liberation Sans (or the matching serif or monospace face, bold or italic like the original) at the same size, colour and place, and says so in the status band ("Written with Liberation Sans: the drawing's font has no “É”"). It is one step of Undo. Cella says so plainly and changes nothing when it can't do it faithfully: a character neither font has, text drawn in a Type 3 font or used as a clipping outline, and text in a block inside another block. It is not carried by sync: a synced document refuses it, as it does cropping and resizing.

The measuring tools are under Measuring. Later, double-click a segment of a polyline, polygon or cloud to add a vertex, and Option-click (Alt-click) a vertex to remove it.

Points you place, markups you move and handles you drag stick to the drawing, its text and pictures, and your other markups: see Snapping.

#Snapping

Cella snaps what you draw to what is already on the sheet. As the pointer comes within reach of something, a marker shows what it caught, and the point you click, the corner you drag or the markup you move lands exactly there.

So a callout's leader can land on a word, a rectangle can hug a note block, and a cloud can line up with the one beside it.

• Snap to Drawing (Tools menu, ⌥⌘N; Ctrl+Alt+N) turns snapping on and off.
• The Snap pull-down in the status band, the target with a ▾ beside the zoom, has the same switch and a checkbox for each kind: Linework, Text, Images, Markups, Guides and Spacing. Tools ▸ Snap To has the checkboxes too. Cella remembers your choice. The target is struck through while snapping is off.
• Hold ⌘ (Ctrl on Windows and Linux) to draw free while you hold it: drawing, moving and resizing ignore everything. Shift still keeps lines at 45° steps and boxes square, and Option (Alt) still puts an arc point or a cut-out.
• Moving a markup snaps by its corners, centre and points, and lines it up with others on a guide. Dragging a handle snaps that corner or point. A markup never snaps to itself.
• Spacing: when a markup you move or a point you draw is about as far from the markup beside it as that one is from the next in the row (or column), or about midway between two, it snaps to the even spacing and both gaps show with their distance, in the sheet's units when it has a scale.
• Highlight, underline and strikeout follow the words instead, and the pen draws free.

#Properties and the style strip

Select a markup and Properties shows everything about it: Subject, Status, Comments, your office's custom columns, stroke and fill colour, line width, opacity, dash and line endings, font size (and for text boxes and callouts Align, Vertical, Margin (pt) and Spacing), Position, Layer, Space, Label, Locked, the author and dates, the replies and the history. With several markups selected, a change applies to them all.

The style strip in the options row under the toolbar is the quick way to change colour, fill, width and opacity. Changing a style with nothing selected makes it the tool's default from then on, as does Markups ▸ Set as Default for Tool with a markup selected.

Right-click a markup for Delete, Duplicate, the order, the status, Lock, Add Link to Markup…, Bookmark This Markup and Add to Tool Chest….

The basic editing keys: Delete removes; the arrow keys nudge (Shift 10 points, Option a tenth); ⌘D duplicates; ⌘Z and ⇧⌘Z undo and redo (Ctrl+Z, and Ctrl+Y on Windows, Ctrl+Shift+Z on Linux); ⌘A selects every markup on the sheet. ⌘C and ⌘V copy and paste markups between sheets and windows.

#Statuses, replies and comments

Every markup can carry a status: None, Accepted, Rejected, Cancelled or Completed (a firm profile can add its own, such as For Review). Set it in Properties, with Markups ▸ Set Status ▸, or from the right-click menu. Bluebeam and Acrobat read the same review states.

Replies are written in Properties: type in the field under the replies and click Reply. They are threaded the way Acrobat and Revu show them, with the author and date of each.

#Text boxes and callouts

Select a text box or callout and Properties shows Align (left, centre, right), Vertical (top, middle or bottom of the box), Margin (pt) (the space between the box's edge and its text) and Spacing (single, 1.15, the default 1.2, 1.5 or double). Set them with nothing selected and the Text Box or Callout tool uses them from then on. They are saved the way Revu keeps them, so a box made in Revu opens with its margin, alignment and spacing, and Revu shows Cella's the same way.

#Arranging and editing markups

The Markups menu has what you need to tidy a sheet. Directions are always as you see the sheet, even on a turned one, and locked markups stay where they are. Each of these is one step of Undo.

• Align ▸ Left, Centre, Right, Top, Middle or Bottom lines two or more markups up with that edge (or centre) of the selection as a whole. Distribute ▸ Horizontally or Vertically spaces three or more evenly. Match ▸ Width, Height or Size makes the others the size of the markup you selected last.
• Group (⌃⌘G; Ctrl+J) makes the selection one group: it selects, moves, copies and deletes as one, and Revu reads it as a group. Ungroup (⌃⇧⌘G; Ctrl+Shift+J) takes it apart.
• Copy Style (⌥⌘C; Ctrl+Alt+C) and Paste Style (⌥⌘V; Ctrl+Alt+V) copy one markup's colours, line, fill, opacity, dashes, endings, cloud border and text settings onto the selection, in this window or another.
• Rotate ▸ 90° Clockwise, 90° Counter-clockwise or 180°, and Flip Horizontal / Vertical (text isn't mirrored).
• Bring to Front (⇧⌘]), Bring Forward (⌘]; Ctrl+]), Send Backward (⌘[; Ctrl+[) and Send to Back (⇧⌘[) change the order; it is saved in the PDF.
• Lock / Unlock (⇧⌘L) stops a markup being moved or changed by accident.
• Move to Layer… puts the selection on a markup layer (type a new name to make one).
• Edit ▸ Select All on Sheet of This Type selects every markup of the selected one's kind on the sheet; Select Similar those with the same subject and colour.
• Properties ▸ Position shows the selection's X, Y (from the sheet's top-left corner), W and H in points, and beneath them the same in the sheet's scale. Type a value and press Return to move or resize exactly: points, or a length such as 12'-6" or 3.5 m in the sheet's scale.
• Hold Shift while dragging a corner handle to keep a box's proportions.

#Revision clouds and tags

Every change in a revision gets a cloud and a revision delta: a small triangle with the revision number. Tools ▸ Revision Cloud (⇧C), or Markups ▸ Revision Cloud, draws both at once: click round the change as with the Cloud tool, click the first point again (or double-click, or press Return) to finish, and the cloud gets a triangle at its top-right corner numbered with the current revision. The cloud and its triangle move, copy and delete together. The first revision cloud in a document starts revision 1, dated today.

Select a revision cloud to see its Revision in Properties: pick another revision from the list, or New Revision… to add one. Description says what changed (it is also the comment); Tag turns the triangle into a circle or a hexagon if your office draws them that way.

Markups ▸ Revision Schedule… lists the document's revisions with their dates, descriptions and how many clouds each has. Add… starts a new revision (it becomes the current one), Set Current (or a double-click) picks another, and you can edit a number, date or description in place: renumbering a revision renumbers its triangles too. Remove takes a revision out of the schedule but leaves its triangles alone.

Markups ▸ Insert Revision Schedule (or Insert Table in that window) puts the schedule on the sheet as a table (No., Date, Description, Clouds) at the bottom right, where the title block's revision block usually is. It keeps itself up to date as revisions are added.

A set that arrives with its revisions already drawn in the title blocks doesn't need typing in: Document ▸ Detect Revisions… reads the revision table in every sheet's title block (the rows of number, description and date, the number often in a triangle; dates such as 10/15/26, 2026-10-15, 15 Oct 2026 or OCT 15 2026) and proposes the schedule. Untick a row to leave it out, or double-click a number, description or date to correct it; a number that two sheets describe differently is marked in red with what the other sheet says. Apply fills the Revision Schedule and marks each sheet with its latest revision and that revision's date, which the Sheet Index, the transmittal and Rename Files' {rev} use; no clouds are drawn, and Edit ▸ Undo takes it all back. A scanned sheet is read from its recognised text, so run Recognize Text (OCR) on it first. The Sheet Index window's Read Revisions… button opens the same window. With a folder set open (File ▸ Set) it reads every sheet of every file, naming each sheet's file beside it, and Apply writes each file's own revisions into it and saves it (a digitally signed file is left as it is and named).

In the Markups List, ⋯ ▸ By Revision groups the clouds and their triangles by revision. In the PDF the triangles are ordinary comments that Acrobat, Preview and Revu show as drawn; Revu's own revision triangles whose subject reads "Revision 3" or "Rev 3" group under that revision.

#Stamps

Tools ▸ Stamps ▸ lists the built-in stamps (APPROVED, REVIEWED, NOT FOR CONSTRUCTION and the rest) and, under My Stamps, your own. Pick one and click on the sheet to drop it; drag to size it. Some fill in the date, the time and your name as they are placed.

Tools ▸ Create Stamp… makes your own: a Title (CHECKED), an optional Subtitle ("by {author} on {date}"), the Fields to fill in each time it is placed (Date, Time, Author, File, Sheet, Page), the Shape (Rectangle, Rounded, Oval or None) and the Colour. It joins Tools ▸ Stamps and the Tool Chest.

Select a placed stamp to change its Title, Subtitle and Shape in Properties; Update Fields fills in its date and name again. Stamps are saved as standard PDF stamps that Acrobat and Revu show as drawn.

The options row under the toolbar sets a stamp's Font, Size and Bold / Italic. The title is bold until you turn Bold off, and Italic slants both lines. Size is the size of the title: type a new one and the stamp grows or shrinks about its centre (Properties' Font size is the same). Times and Courier are saved as they look; a Mac font the PDF doesn't name shows in Cella and saves in Helvetica. Picture stamps have no font.

#Signatures

Tools ▸ Signatures ▸ Add Signature… makes a picture of your signature, three ways:

• Draw it on the pad with the trackpad or mouse (and your initials on the small pad, if you like). Clear starts again.
• Type your name and pick a font: the script faces come first, then every font on the computer. Your initials are made from the first letters.
• Image: choose a scan or photo of your signature on white paper (PNG or JPEG). The paper turns transparent; move Remove paper lighter than until only the ink is left.

Choose black or blue ink and Save Signature. It is kept in the Tool Chest under Signatures (with an "(Initials)" entry when you saved initials) and is ready to place: click on the sheet to drop it about 1.5 inches wide, or drag to size it. Later, pick it from Tools ▸ Signatures or the Tool Chest. Turn on Tools ▸ Signatures ▸ Date Beside Signature to put today's date next to it; the two move together.

A placed signature is a picture, like a snapshot: other PDF viewers show it, and Flatten makes it part of the drawing. It is not a digital signature. It does not prove who placed it or that the drawing hasn't changed since, and it doesn't fill a PDF's signature fields. Your signatures are kept with your other Tool Chest tools in Cella's settings on this computer, encrypted with a key only your account can use (your login keychain on a Mac, Windows' own data protection, your desktop's keyring on Linux). They never go to a sync project's Project Tools, and exporting a tool set that holds them warns you first, because the exported file keeps them as plain pictures.

To sign a drawing digitally, choose Document ▸ Sign Digitally…, pick a certificate from your keychain (on Windows, your certificate store; on Linux, a .pfx file), where it goes (over a signature picture you have selected, a box at the bottom right of the sheet, or invisible), and a reason and location if you like; Sign saves the file with the signature. Turn on Lock the document after signing to certify it with no further changes allowed. Document ▸ Signatures… lists a file's signatures, who signed and whether each is still valid.

#The Tool Chest

The Tool Chest keeps markups you use again and again. Right-click a markup ▸ Add to Tool Chest…, name it, and it appears in the toolbar's Tool Chest menu with its colours, text, stamp, subject and layer. Picking it draws more of the same; a grouped markup (a punch key: a circle with its letter) becomes a one-click tool.

Tools ▸ Manage Tool Chest… lists every tool by set. Drag a tool to reorder it or onto another set; drag sets to reorder the menu. Select a tool to rename it or change its subject and default comment (the text each new markup starts with), and see a preview. Duplicate, Delete and Move to Set work on the selection. Importing and exporting tool sets is under Working with Bluebeam files.

Project Tools (with a synced document): share tools with everyone on the project. In Manage Tool Chest…, select a tool or a set and choose Project Tools ▸ Share with Project…; the tools appear under Tool Chest ▸ Project Tools for every member while a document of the project is open, and stay there when you are offline. Anyone on the project can share more or choose Remove from Project Tools; if two people change them at once, the later change is kept and the other person is told. Your sync server needs the October 2026 Atrium; an older one shows no Project Tools.

#Legends

Markups ▸ Insert Legend… puts a table on the sheet that sums up its markups, the way Revu's Legend does: a swatch in each subject's colours, the subject, how many there are and their length, area and volume totals.

Choose a title, what to group by (subject, status, author or layer), whether it covers this sheet or every sheet, and which columns to show. The legend keeps itself up to date as you draw, move and delete markups, so it prints right with the sheet.

Select it to change its options in Properties. Untick Live to freeze it as it is (for an issued set) and press Refresh when you want it brought up to date. Drag it anywhere; drag a handle to give it a fixed size, and rows that don't fit end in "n more…". It is saved as an ordinary PDF text annotation, so Acrobat, Preview and Revu show the table too. On a rotated sheet the legend reads upright, at the sheet's top right as you see it, like text you add there.

#Sequences

A sequence numbers boxes as you place them: door tags D-01, D-02, D-03; grid letters A, B, C; RFI 007, RFI 008. Choose Tools ▸ Sequence…, give it a name (Door Tag), a prefix (D-), the start, the step, the padding (2 gives 01, 02) and the format (1, 2, 3 or A, B, C), and whether the boxes are text boxes or callouts. Every click then drops a box with the next value, sized to fit; press Esc when you are done. Keep in Tool Chest saves the tool, so it is one click next time.

The document remembers where each sequence has got to, so after a save and reopen the next box carries on (D-05 after D-04), in both panes of Split View, and boxes a colleague places on a synced document move yours on too. Select a box to see its sequence in Properties: Prefix, Suffix, Format, Next (type a value to jump), Step and Padding; untick Numbered (sequence) to keep the text as plain text, or tick it on ordinary text boxes to make them a sequence. Renumber ▾ puts a sequence back in order: In Order numbers the boxes in the order they were placed, By Position in reading order across the sheet. If you delete a box from the middle, Cella offers to renumber the ones left.

#Counts

The Count tool (⇧⌥C; Shift+Alt+C) places a symbol at every click and keeps a running total: one count per run of the tool, so start it again for the next kind of thing. Name the count in Subject (Duplex Receptacle) and the Markups List row reads "Duplex Receptacle · Total 14 EA"; legends count it the same way.

In Properties, Symbol chooses what marks each point (a dot, circle, check, cross, square, triangle, diamond, a numbered disc, or a symbol from a tool set), Size sets it in points, and Show numbers writes each point's number beside it. Total shows how many there are, with Select All. To take one point out, select the count, click that point (a ring marks it) and press Delete; the points after it renumber. Option-click a point removes it too.

#Redaction

Bid amounts, personnel notes and client names can be taken out of a set for good, the way Acrobat Pro does it: mark first, then apply.

• Mark text: select it with the Select tool (drag, double-click a word, triple-click a line), then Edit ▸ Mark Text for Redaction (or right-click ▸ Mark for Redaction).
• Mark every place a word appears: search for it in the sidebar, then Edit ▸ Mark Search Results for Redaction. Applying these marks also removes bookmarks whose titles contain it.
• Mark an area: Markups ▸ Mark Area for Redaction, then drag a rectangle over a drawing, a picture, a stamp or a signature block.
• Marks show as red outlines with hatching; nothing is removed yet. Move, resize, delete or undo them like any markup. In Properties give a mark an Overlay text ("REDACTED") and a Colour. They save as standard redaction marks that Acrobat and Revu understand.

Markups ▸ Apply Redactions… removes, under every mark:

• text, letter by letter, so the rest of the line stays exactly where it was;
• linework: a line, hatch, fill or curve that crosses a mark's edge is cut at the edge, so the part outside looks as before and nothing of it is left inside (this includes text the drawing program turned into linework, and dashed lines, whose dashes don't shift);
• the letters' shapes in the fonts: when a letter appears only under marks, its outline is taken out of the font embedded in the file, so it can't be recovered from there;
• shadings and gradients, cut out of the mark;
• pictures: the covered pixels are painted in the mark's colour. A JPEG photo partly under a mark is stored again without compression loss (the copy of that picture is larger);
• comments and form fields over a mark.

Each area is painted in its colour with its overlay text. It can't be undone, so it writes a new file ("A-101 redacted.pdf") and your document keeps its marks; choose Replace the original to rewrite the file itself (the original stays in the .cella folder). Tick Also remove document metadata to drop the title, author and keywords too. When the file has embedded files (attachments: a spreadsheet, a model), the sheet lists them with Also remove the embedded files, ticked.

When it is done, Cella reads the copy back and looks under every mark again. The summary ends with Verified: nothing remains under 7 marks, or says what is still there and on which sheet.

What is not removed: a letter that only just touches a mark (less than about a sixth of it under the mark) stays, visible beside it; a line much thicker than the mark is narrow stays under the paint; bookmarks are only removed for marks made from a search; link targets, page labels and form-field values elsewhere are not searched. Check the copy before you send it (search it for the words you removed).

#Flattening

Markups ▸ Flatten Selected and Flatten All draw markups into the sheet itself, so nobody can move or change them; Unflatten takes back what Cella flattened. File ▸ Export Flattened Copy… (File ▸ Export ▸ Flattened Copy… on Windows and Linux) writes a flattened copy for a contractor and leaves your working file editable.

File ▸ Export PDF/A-2b Copy… (File ▸ Export ▸ PDF/A-2b Copy… on Windows and Linux) writes an archive copy for record sets: the markups flattened, every font embedded (Helvetica, Times, Courier, Symbol and Dingbats are replaced by matching fonts Cella ships), an sRGB colour profile and the archive metadata. Before anything is saved it lists what it changed and what it left out: links that open programs, scripts, and attached files (tick Keep attachments as PDF/A-3 to keep them; the copy is then PDF/A-3b). A drawing that uses a font which isn't embedded and that Cella has no replacement for (Calibri, say) can't be archived: Cella names the font, and exporting the drawing again with its fonts embedded fixes it. The copies of our test sets pass the veraPDF 1.30.0 validator (PDF/A-2b, and PDF/A-3b with attachments kept). If your archive requires a validation report, run a validator on your own copy.

#Forms

Transmittals, RFIs, submittal cover sheets and inspection checklists that arrive as PDF forms fill in place. The status band says how many fields a form has.

• Click a field and type. Tab moves to the next field (and on to the next sheet), Return commits, Esc puts back what the field had. Check boxes and radio buttons toggle with a click or Space; list boxes take ⌘-click for several choices.
• Forms ▸ Highlight Fields tints every field (required ones outlined in red).
• Forms ▸ Clear Form… empties the form; Flatten Form… makes the values part of the sheets.
• Forms ▸ Export Form Data… saves the values as JSON or FDF (Acrobat reads FDF); Import Form Data… fills a form from either.
• Calculated and formatted fields work as in Acrobat. Totals, products, averages and simple formulas (Quantity × Rate) fill themselves in as you type, in the order the form sets; amounts show as currency ("$1,250.00"), percentages as "8.0%", dates, times, zip codes, phone and Social Security numbers in the form's format. A field shows its plain value while you type in it.
• A date field opens a small calendar when you click into it: click a day, or just type the date (10/15/2026, 2026-10-15 or Oct 15 2026 all work; it is written in the form's format).
• A value the form doesn't accept (a percentage over its limit, a date that doesn't exist, letters in an amount) is refused with the form's own message, and the field keeps what it had.
• Forms can carry other scripts Cella doesn't run (pop-up messages, custom code). Those fields still fill in; the status band says "(1 script not run)" after the field count, and Properties marks the field.
• Save writes the values into the PDF, so Acrobat, Preview and Bluebeam show them. View-only Cella shows filled-in values but can't change them.

#Measuring

Measuring needs a key or the trial. Measurements are written into the PDF as real measurement annotations, so Bluebeam and Acrobat show the same values.

#Setting the scale

Set the sheet's scale first: Tools ▸ Set Scale…, or click the scale in the status band, and pick a preset (architectural, engineering or metric) or Custom. Or calibrate from the drawing: Tools ▸ Calibrate (⇧⌥K; Shift+Alt+K), click two points a known distance apart and type the distance (12'-6" works).

Both end with Apply to: this sheet, every sheet of the same paper size (handy when the plans are one size and the details another), or all sheets. Each sheet keeps its own scale; the status band, the sidebar and Properties show the one you are on. A sheet without a scale says "No scale", and the first measuring tool you pick on it asks for one.

For a detail sheet with several scales, Tools ▸ Scale Region (⇧⌥R; Shift+Alt+R): drag round the detail and pick its scale; measurements that start inside it use that scale. Tools ▸ Remove Scale Regions on This Sheet takes them off.

#The measuring tools

On Windows and Linux the keys are Shift+Alt and the letter.

Dynamic Fill (⇧⌥F; Shift+Alt+F) measures a room with one click: hover inside it and Cella tints the region its walls enclose, with the area by the pointer; click and it becomes an ordinary Area measurement (cut-outs, Properties and totals as for one you drew). Fill gap in the options row (0–12 pt, 4 by default) closes door openings narrower than that. If the fill would run out of the room, Cella says the area isn't closed: raise Fill gap, or draw the room with the Area tool. Esc puts the tool down.

#Drawing measurements precisely

• While you draw, a readout by the pointer shows the length and angle of the segment you are drawing and the total so far.
• Hold Shift to keep the segment at 0°, 45°, 90° and so on.
• Points snap to the linework, text and other markups as you draw (see Snapping); hold ⌘ (Ctrl) to place one free.
• Type a length while drawing a length, polylength, area, perimeter or volume: 12'6, 12'-6 1/2", 6", 3.5m or 350mm, then Return. The segment is fixed at that length in the direction you are pointing, and you carry on drawing. A plain number is in the sheet's unit. Delete corrects; Esc drops it.
• The Length tool works by dragging, or by clicking at one end and then the other.
• Arcs: with the Polylength, Area, Perimeter or Volume tool, hold Option (Alt) and click a point the next segment should curve through, then click where it ends. Select the measurement to bend an arc by its middle handle; Properties' Arcs row has Straighten. Lengths and areas count the true curve.

#Dimensions

Set a length's Style to Dimension in Properties for a drafted dimension: extension lines at both ends, ticks (Slash), dots (Circle) or arrows at the ends, and the value on the line (Text: On the line) or above it (Above the line). Offset moves the dimension line away from what you measured (negative: the other side). Selected, drag the handle at the value to slide it along the line, and the other handle to move the line itself. Acrobat and Bluebeam show the dimension as drawn.

Slope and 3D length. For a pipe run or a roof, type a Slope in Properties for a length or polylength: a ratio (1:12), a percentage (8 %), degrees (4.5°), or a rise as a length (3'-6"). The value then shows the plan length and the true length with the slope, such as 12'-4" (3D 12'-9", 1:12). The Markups List, its CSV and Excel export gain 3D Length and Slope columns (the plan length stays under Measurement), and the totals add the 3D lengths. A rise is the whole run's; one slope or rise applies to every segment of a polylength. Clear the field to make it flat again. When a polylength's legs change grade, select it alone and use the Segments table in its place: give each leg its own slope or rise (blank is flat), or Apply to all; the 3D length is the sum of the legs' and the value says mixed, such as 32'-0" (3D 32'-7 5/8", mixed). Bluebeam and Acrobat still measure the plan length.

#Areas and cut-outs

A stairwell, a shaft or a courtyard shouldn't count in the floor area. Select the area (or volume) and choose Markups ▸ Cut Out from Area, then draw the opening as a polygon: click each vertex and finish by clicking the first or last point again, double-clicking or pressing Return. With the Area or Volume tool you can also hold Option (Alt) on the first click while one area is selected. The hole's area comes off the area (a volume is the cut area times the depth). The cut-out has to lie inside the outline; Cella says so if it doesn't. Cut as many openings as you need.

Properties shows a Cut-outs row with the count, Cut Out and Remove (which gives the area back whole). The perimeter stays the outline's alone; tick Cut-out edges in perimeter to add the openings' edges. The Markups List, totals, legends and the CSV all use the reduced value, and Acrobat, Preview and Revu show the openings. Cella saves the openings in the area's outline the way Revu is believed to keep them, and reads a Revu area's openings back as cut-outs; this has not yet been checked against Revu itself (see What's not there yet).

#Custom columns and formulas

Markups List ⋯ ▸ Custom Columns… is the list of columns your office adds to every markup (Ball in Court, Division, Due, Cost Impact). Each column has a name and a type:

• Text; Number, with a Unit (a currency sign shows before the number, LF or SF after it) and Decimals; Choice, a pop-up of the options you list, separated by commas; Checkbox; and Formula.
• A Formula column works its value out from the markup's measurement and its other columns, so a take-off prices itself: area * [Unit Cost]. A formula can use length, area, volume and count (in the units the sheet's scale shows: feet, SF, CY, each), the other columns by name in square brackets, + - * / ^ and brackets, comparisons, and round(x, 2), if(cond, a, b), min, max, abs, ceil and floor. The Insert menu offers them all, and under the formula Cella says at once whether it reads ("✓ The formula reads") or what it can't find. A markup the formula can't be worked out for shows #ERR.

Use + to add a column and − to remove one (its values go when you save); a column keeps its values when you rename or retype it. The columns travel with the file and show in Bluebeam's custom column data. Fill them in in Properties, or double-click a row of the Markups List. File ▸ Set ▸ Apply Columns to Set… gives every file of a set the same columns.

#Take-offs and the CSV

Sort the Markups List by subject and it becomes a take-off: each subject a group with its count and totals, and number and formula columns summed too (Area 1,133.44 SF · Count 21 EA · Cost Impact $7,000). Filter to total one subject or one sheet. ⋯ ▸ Export CSV… (⇧⌘E, File ▸ Export Markups as CSV…; File ▸ Export ▸ Markups CSV… on Windows and Linux) writes every column, with a heading line and subtotals per group and the totals at the end, ready for a spreadsheet. ⋯ ▸ Export to Excel… writes the same take-off as an Excel workbook, with the numbers as numbers and a Totals row that adds up. See The Markups List.

For an estimator's summary, choose File ▸ Export Take-off Summary… (File ▸ Set ▸ Export Set Take-off Summary… for the whole set). It pivots the listed measurements: a row per subject (or per tool when a markup has no subject), a column per space, layer, sheet or status (Group columns by; by file too for a set), each cell the quantity summed in the units the list shows (LF, SF, CY, EA, or metric), with a Units column, a Total for each row, your number and formula columns (a cost column, say) summed beside it, and a bold Totals row per unit. Save it as an Excel workbook or a CSV. Export to Excel can add the same table as a second worksheet, Take-off, after the markups: pick the grouping under Take-off sheet by in its save panel, or None to leave it out.

#The Markups List

View ▸ Show Markups List (⌥⌘M; Ctrl+Alt+M) shows every markup in the document, under Properties: a swatch in its colours, the subject, then its measurement, comment and status, with the sheet and the author's initials at the right. Click a row to go to the markup and select it; double-click to edit its subject, comments and custom columns. View-only Cella shows the list read-only.

#Sorting and grouping

The ⋯ menu sorts the list As Drawn, By Subject, By Sheet, By Author, By Date, By Status, By Revision or By Space. Sorted by subject, sheet, author, status, revision or space, the markups run in groups, each under a header with its name, its count and, when it holds measurements, its totals (AREA MEASUREMENT · 2 Area 1,133.44 SF). Click a header to fold its group away and again to open it; click the count to select every markup in the group, for instance to restyle a whole subject at once. Turn Show Group Headers off for a plain sorted list.

A group of markups (a punch key) is one row with "Group of 3" under it; the totals and the CSV still count every markup.

#Filtering and totals

Type in the filter field to show only the markups whose text matches; group names match too ("no author", "revision 3"). The line under the list totals everything listed (Length 191'-6" · Area 1,133.44 SF · Count 21 EA), so filter to total one subject or one sheet. The Filter button beside the field narrows the list by Status, Author or Sheet (pick several, or This Sheet), to Measurements Only, or to what changed since a time; the caption then reads "12 of 40", and Clear Filters shows everything again.

Views. Once the list is sorted, grouped and filtered the way you like, ⋯ ▸ Views ▸ Save View… keeps that arrangement under a name: the sort and grouping, the filter, Changed Since, Show Modified By, Whole Set and the columns. Pick it from ⋯ ▸ Views later, in any document, to put the list back that way; the view the list is arranged as has a tick. Three come with Cella: Default, Review (grouped by status, with the author and date) and Take-off (only the measurements, grouped by subject with their totals). Save over a view, or a built-in, with Update “Review”; Reset puts a built-in back; Manage Views… renames and deletes your own. Views travel in profiles, so an office can hand everyone the same ones.

#With the keyboard

Return shows the selected markups on the drawing; Delete deletes them (asking first when there are several); ⌘↑ and ⌘↓ jump between groups; ↑ and ↓ step over the headers. On Windows and Linux F2 edits a row.

#The whole set

With a folder set open, the ⋯ menu starts with This File and Whole Set. Whole Set lists every file's markups at once, with the file name at the right of each row. Sort By Sheet (By File) to group them by file; the totals, group totals and the CSV run across the whole set, each measurement in its own file's scale. Double-click a markup of another file to open that file and go to it.

#Summary PDF, CSV and Excel

• ⋯ ▸ Export CSV… (⇧⌘E): every column, grouped as the list is, with subtotals and totals. In Whole Set the CSV starts with a File column.
• ⋯ ▸ Export to Excel… (also File ▸ Export Markups to Excel…, and File ▸ Set ▸ Export Set to Excel… for the whole set) saves an Excel workbook (.xlsx) of the markups listed, after the filter, with the CSV's columns. Unlike the CSV its cells are typed: dates are dates, lengths, areas, volumes and counts get number columns of their own (Length (LF), Area (SF), Volume (CY), Count (EA)), number and formula columns are numbers in their units, and checkboxes are TRUE or FALSE, so Excel can sort, filter and add them up. The header row stays in view as you scroll, the columns are sized to their contents, and a last Totals row sums the number columns with formulas. When the list is grouped the first column names each markup's group, and One worksheet per group in the save dialog adds a worksheet for each group (each subject, sheet, author, status, revision or space) after an All markups sheet, each with its own totals. In Whole Set the workbook starts with a File column. Numbers and LibreOffice open it too.
• File ▸ Export Markups to DXF… (File ▸ Export ▸ Export Markups to DXF… on Windows and Linux) hands the markups to a CAD program as a .dxf drawing. Choose This Sheet or Every Sheet (one file per sheet, named after the sheet) and whether each Cella layer or each subject becomes a CAD layer. The drawing is in the sheet's real units from its scale, with its origin at the sheet's lower-left corner, so a wall measured 10'-0" is 10 feet long in AutoCAD; a sheet with no scale is written in points, and Cella says so. Lines, polylines, clouds, rectangles and ellipses keep their shapes (arcs as arcs), text boxes and callouts become text with their leaders, measurements become their lines with their values as text, counts a point and a number at each spot, and stamps and snapshots a box with their name. Colours, line weights and dashes come along; hidden and flattened markups stay out. Each piece carries the markup's id, subject and custom columns as Cella data, and the Spaces come in as outlines on a layer of their own.
• File ▸ Export Markups Summary PDF… (File ▸ Export ▸ Markups Summary PDF… on Windows and Linux) makes a report with a picture of each markup and its details, comments, custom columns and replies. File ▸ Set ▸ Export Set Summary PDF… does one for the whole set, with a contents page.

#History and Changed Since

Select a markup and Properties ▸ History tells its story: who created it, who changed it and when, each status it went through ("Status set to Accepted"), who replied, and when it moved to another sheet. Cella keeps this in the PDF itself (up to 50 events per markup), so it travels with the file and needs no server; on a synced document the server's record is added (marked ⇅). Markups from other programs show what their own dates and replies say.

In the ⋯ menu, Show Modified By adds who last changed each markup to its row, and a Modified By column to the CSV. Changed Since… lists only the markups created or changed after a date and time, or since the last revision. Markups ▸ Show Changes Since… does the same and outlines every changed markup on the sheet in orange, so a reviewer sees at a glance what is new since the last issue; Markups ▸ Clear Changes takes the outlines away.

#Sets and documents

#Folder sets

File ▸ Open Folder as Set… (⇧⌘O) opens a folder of PDFs as a set. The Set tab of the sidebar lists the files with their markup counts (kept in .cella/set-index.json in the folder, so they show before any file is opened). Click a file to open it in the same window; a file with unsaved changes is saved first.

File ▸ Set ▸ works on every file of the set, with a progress sheet you can cancel. The open file is saved first if it has changes.

• Print Set… and Export Transmittal…: see Printing and Transmittals.
• Export Set Summary PDF…: one report with a contents page and a section per file.
• Export Set CSV…: the Whole Set list as CSV, with a File column.
• Flatten Set…: flattened copies of every file into another folder; your files stay editable.
• Set Status for Selection…: select markups in the Whole Set list (across files), then set their status in one go; each file is saved, nothing else in it changes.
• Apply Columns to Set…: gives every file this file's custom columns (matched by name, so values a file already has stay put).
• Compare Set with Folder…: compares each file with the file of the same name in the other issue's folder (revision suffixes such as _R2 ignored) and clouds the changes on layer Compare.

File ▸ Set ▸ Rename Files from Sheets… names each PDF of the set after its first sheet: its number and title from the Sheet Index, Detect Sheet Numbers or the sheet names. Type a pattern with {number}, {title}, {rev} (the revision from the file's revision schedule, if it has one) and {file} (the name now); the default is {number} - {title}, and characters a file name can't hold become "-". The preview lists every file's current and new name before anything moves; names in red would collide (two sheets with the same number, or a name already in the folder) and those files stay as they are. Rename moves the files with everything Cella keeps beside them (markup logs, backups, search indexes, sync links), keeps the Set list's order, and an open file stays open under its new name. File ▸ Set ▸ Undo Rename puts the last rename's names back.

#Sheet index

Many sets list their drawings in a table on the cover ("SHEET NO. / SHEET TITLE / REV"). Tools ▸ Sheet Index… reads that table from the first sheets of the open file and shows each row with the sheet it matches by number (in a folder set: any file of the set). Fix a misread number or title by double-clicking it, untick rows to leave out (Cella can take another table on the sheet, such as a wall-type schedule, for an index: untick its rows), then Apply: each matched sheet is named by its number and keeps its title, which the Sheets list, the strip and the status band show. Tick Move the sheets into index order to reorder them (in a set, the Set list follows the index). The report lists index rows with no sheet and sheets the index doesn't list. Save to write the numbers and titles into the PDF; in a set each changed file is saved for you.

#Slip-sheeting

When a new issue arrives, slip-sheet it in and keep every markup:

• File ▸ Slip-Sheet from Newer Issue… replaces sheets with the newer PDF's, matched by sheet number, keeping every markup in place. A one-page PDF with no match offers to replace the sheet on screen.
• File ▸ Slip-Sheet Set from Folder… does it for a whole folder set, pairing each file with the file of the same name in the folder you choose (revision suffixes like _R2 or rev 3 ignored), and reports what it replaced and skipped.

#Page operations

The Sheets menu and a right-click on a row of the Sheets list work on the selected sheets (⌘-click or Shift-click rows to select several), or on the sheet on screen:

• Rotate Right and Rotate Left (⌘R, ⌘L) turn sheets a quarter turn. Markups and measurements turn with the drawing and keep their values; text you add to a turned sheet reads upright.
• Move Sheet Up / Down, Move Sheet To…, or drag rows in the Sheets list to reorder.
• Insert Pages… (also in File) adds every page of another PDF after the selected sheet, with its markups, scales and links.
• Extract Sheets… (also in File) saves the selected sheets as a new PDF with their markups, scales, custom columns and bookmarks; this document stays as it is.
• Insert Blank Page… (also in Document) adds empty sheets; see Blank pages below.
• Insert Image Pages… (also in Document) makes a sheet of each picture you choose; see Blank pages below.
• Delete Sheet… removes sheets and their markups after asking.

Every one of these is undone with ⌘Z until you close the document, even after saving. On a document connected to a sync project they go to everyone in the project as you make them, and so does their undo: ⌘Z turns, moves, deletes or brings the sheet back for everyone; see Sharing and sync. Blank pages, cropping and resizing travel the same way: everyone gets the blank sheet, the crop or the new paper size, with the sheet's markups, scale, links and Spaces moved with its drawing, and ⌘Z takes it back for everyone. Cropping and resizing need an up-to-date Atrium; with an older one a synced document refuses them until you disconnect it (Sync ▸ Disconnect Document). Extract, Split Document and Export Sheets as Images work either way.

#Combining files

File ▸ Combine Files… joins several PDFs into one, in the order you set. Add files with Add Files…, drop PDFs onto the list, drag rows to reorder them and Remove the ones you don't want; with a folder set open, Combine the Set lists every file of the set in order. Choose:

• Markups: keep them as markups you can still edit, or flatten them into the sheets.
• Page labels: each file's own sheet names (from the file, or read from each title block), or names made from the file names.
• A bookmark per file, with the file's own bookmarks under it, or a bookmark per sheet when it has none.

Combine… asks where to save ("A-101 combined.pdf") and opens the new file. Every markup comes along exactly as it was, Bluebeam's data included. Layers with the same name become one layer, and form fields with the same name are renamed ("Date_2") so both keep their values. The files themselves are never changed.

#Reducing file size

File ▸ Reduce File Size… makes a smaller copy of the document:

• Pictures: Good for sharing (150 dpi, JPEG 80), Small for email (100 dpi, JPEG 65), Custom, or Keep as they are. Scans and photos drawn finer than that, measured by how large they appear on the sheet, are averaged down and stored as JPEG (gray scans stay gray), so a scanned set of 90 MB typically comes down to a tenth; the summary says how much ("31 pictures recompressed: 92.4 MB → 11.8 MB"). Black-and-white (1-bit) scans are stored the way fax machines store them (CCITT Group 4), at their own resolution, or at 200 dpi when they were scanned at more than 400 dpi; they never go below 200 dpi, so line work and small lettering stay legible ("4 black-and-white scans recompressed: 9.6 MB → 1.2 MB"). Drawings made of lines are not pictures and are never touched, nor are pictures with transparency, pictures under 150 KB and JBIG2 scans.
• Clean up stores fonts and pictures that appear several times once, and drops what earlier edits left behind. Flatten markups draws them into the sheets.
• Discard page thumbnails, attached files and other programs' private data (Illustrator keeps a second copy of its artwork in exported PDFs). Cella's own data always stays.

Press Check Size to see "Before 48.2 MB → After 9.1 MB" before anything is written, then Save As… for a copy ("A-101 reduced.pdf") or Replace to make this file the smaller one (a copy of the original is kept in the .cella folder beside it). Markups, links, bookmarks, page labels and measurements stay exactly as they were; Cella reads the smaller file back and refuses to write it if anything is missing.

#Headers and footers

Document ▸ Headers & Footers… puts text at the top and bottom of every sheet, or of a range of sheets: left, centre and right in the header and in the footer. Type text and add these from Insert:

Bates numbers count on from sheet to sheet. Choose the text size and the margin; the preview shows the first sheet. Put them as markups (on the layer Header/Footer: edit, move or delete them like any text box, or hide the layer) or into the page content (they print and show in every viewer like the drawing itself). Applying again replaces the earlier ones. Document ▸ Remove Headers & Footers takes off every header and footer Cella added.

#Splitting a document

File ▸ Split Document… makes several PDFs out of the open one. Split by:

• Sheet ranges: type them, such as 1-3, 4-6, 7- (each range is a file; 7- runs to the last sheet).
• Every N sheets: files of 2, 5, 10 sheets.
• Top-level bookmarks: each top-level bookmark starts a file, named after the bookmark.
• Sheet-name prefix: the discipline letters, so A-101, A-102 … go into one file, S-201 … into another, M-301 … into a third.

The list shows every file it will make ("Tower - A.pdf", with its sheets) before anything is written. Choose the folder and what the names start with, then Split. Each file keeps its sheets' markups, bookmarks, scales and custom columns, as Extract Sheets does; the open document stays as it is.

#Blank pages

Sheets ▸ Insert Blank Page… or Document ▸ Insert Blank Page… adds empty sheets after the sheet on screen (or before it, at the start, at the end). The size is the sheet on screen's, or any of Arch A–E, ANSI A–E and A4–A0, portrait or landscape. ⌘Z takes them out again.

Sheets ▸ Insert Image Pages… turns pictures into sheets: choose one or more JPEG, PNG, HEIC or TIFF files and each becomes a sheet after the sheet on screen (or at the end), named after its file. A sheet is the picture's own size at the resolution the file gives (a 300-dpi letter scan comes in at 8½ × 11 in; a picture that gives none is taken at 150 dpi, which you can change), or This sheet's size or a paper such as Arch D, with the picture scaled to fit and centred on white. JPEGs go in exactly as they are, with no loss; a PNG's transparent parts become white. On the Mac you can also drop pictures on the Sheets filmstrip or the Sheets list. ⌘Z takes them all out again, and on a synced document the new sheets reach everyone in the project.

#Cropping and resizing pages

Document ▸ Crop Pages… sets what a sheet shows and prints: trim its margins (top, bottom, left, right, in inches, millimetres or points), crop it to a size, or Remove the crop. Apply it to this sheet, the sheets selected in the Sheets list, or all of them. To draw the crop instead, choose Document ▸ Draw Crop Box (or Draw on Sheet in the sheet) and drag a rectangle over the drawing; Crop Pages opens with the margins it leaves, ready for that sheet or the others (coming from Draw on Sheet, with the units and sheets you had chosen). It works in either pane of Split View showing this document. Markups stay exactly where they are on the drawing; one cut off by the crop comes back when the crop is removed.

Document ▸ Resize Pages… puts sheets on another paper. Scale to fit the paper shrinks or enlarges the drawing (its hatching and fills too) with its markups, and changes the sheet's scale with it, so a wall that measured 12'-6" still does. Keep its size leaves the drawing as it is and grows (or trims) the paper around it, centred or from the top-left corner. Both are undone with ⌘Z.

#Sheets as pictures

File ▸ Export Sheets as Images… saves one PNG or JPEG per sheet, at 72 to 600 dpi, with or without the markups, into a folder you choose: "Tower - A-101.png", "Tower - A-102.png" … Each picture is the sheet as it reads on screen (turned sheets upright, crops applied). A very large sheet at a high resolution is made as large as Cella can draw it (about 15,000 pixels across at most); the sheet says so before you export.

#A stamp on every sheet

Document ▸ Apply Stamp to Every Sheet… puts a copy of a stamp on every sheet, or on the sheets selected in the Sheets list. Select a stamp you have placed first to copy it to the same spot on every sheet (the same distance from the same corner, so one in the title block lands in each title block), or pick a stamp from the list and a corner. A stamp you turned (Markups ▸ Rotate) is copied turned. Each copy is an ordinary stamp you can move or delete, with its own sheet's name and number filled in; one ⌘Z takes them all away.

#Printing

File ▸ Print… (⌘P; Ctrl+P) opens the Print sheet, also when the trial has ended:

• Printer: your printers; the choices below are remembered for each.
• Sheets: this sheet, all of them, a Range (1-3, 7 or A-101), or the ones selected in the Sheets list.
• Markups: Print markups (in colour), Form fields, and a Markups summary at the end.
• Scale: Fit to paper (a half-size set on 11×17), Actual size (100%) or Custom %; Tile large sheets prints a full-size sheet across several smaller pages with a ½" overlap and crop marks; Auto-rotate to fit.
• Paper: the printer's choice, or Letter, Tabloid, Arch C, D or E when the printer offers them.
• Colour: Colour, Grayscale, or Markups in colour, drawing in grayscale, the review set where red marks stand out on a grey drawing. Print as image under it sends each page as one picture at 150, 300 or 600 dpi, for printers and print shops that stumble on transparency, unusual fonts or very large CAD drawings (in grayscale, black-and-white pages go as crisp fax-style images).
• Copies.

The preview shows the first sheet on its paper. Print… continues to the usual print dialog; Print as PDF… saves exactly what would print. Unsaved markups print without saving the file.

On Windows and Linux the dialog is the same without the preview. On Windows, the print dialog that follows chooses the printer, copies and paper, and its own scale setting decides Fit to paper and Actual size. On Linux the printer, paper, copies and scale go straight to the printer (CUPS).

File ▸ Set ▸ Print Set… is the Print sheet for the whole set (or the files selected in the Set list): the same choices apply to every file, and Sheets of each file (empty for all, or 1 for each file's first sheet) picks the sheets. The files print as one job with a bookmark per file, or tick One job per file. Transmittal cover listing the sheets puts a page first that lists every sheet printed (number, title, revision, file). Print as PDF… saves the whole set as one PDF with the same bookmarks.

#Transmittals

File ▸ Set ▸ Export Transmittal… writes a one-page transmittal: the project (the folder's name), today's date and the drawing index (from Tools ▸ Sheet Index…, or the cover of the open file) with which sheets this set includes, in which file and at which revision; sheets the index doesn't list are added at the end.

#Batch operations

Everything under File ▸ Set ▸ runs file by file across a folder set: summaries, CSV, flattening, statuses, columns, comparing and printing. Each shows a progress sheet ("Summarising 3 of 25…") with Cancel, which stops after the file in hand, and ends with a report of what it did and any files that failed. Slip-Sheet Set from Folder… and Combine Files… with Combine the Set work across the set too.

#Working with Bluebeam files

Cella is built to sit beside Bluebeam Revu: the PDFs it saves are the PDFs Revu reads, and Revu's PDFs open in Cella with everything in them.

#What round-trips

• Markups are standard PDF annotations. Revu's own private data on each markup (custom columns, spaces, labels, groups, review states, its measurement data) is read and kept, and a markup you didn't touch is saved byte for byte as it was, appearance included.
• Measurements carry the PDF's measurement dictionaries and the sheet's scale (viewports), so Revu reads Cella's scales, lengths, areas, counts and volumes, and Cella reads Revu's.
• Custom columns are written where Revu keeps its custom column data.
• Groups (punch keys) are written the way Revu writes them and come back as groups.
• Text boxes keep Revu's margin, alignment and line spacing both ways.
• Statuses and replies are the review states and threaded replies Revu and Acrobat show.
• Sheet names are written as page labels, bookmarks as the PDF's outline, links as standard link annotations, stamps as standard stamps.

#Tool sets

Tools ▸ Import Bluebeam Tool Set… reads a tool set exported from Revu (Tool Chest ▸ Manage Tool Sets ▸ Export, a .btx file); the zips from Bluebeam's community tool set library work too. The tools arrive as a set under its name with their colours, line styles, text, stamp names and layers. Punch keys, symbols and other fixed-size tools drop onto the sheet with one click and stay grouped. Picture stamps (trees, people, doors) come in as linework at their size, in their colours (as pictures when they hold text or images). Sequence tools come in as sequences and count tools as Count tools (none of Bluebeam's community tool sets has either kind, so tell us if one of yours doesn't come in as it should). Tools Cella doesn't draw (file attachments, form fields) are listed as skipped.

In Tools ▸ Manage Tool Chest…, Export "Set" as a Revu Tool Set… writes a .btx that Revu imports (Tool Chest ▸ Manage Tool Sets ▸ Import), and Export All Sets… writes one per set into a folder. Export Tool Chest… saves everything as a .cella-tools.json for another Cella user; Import… reads it back (or a .btx, or the tool sets in a Revu profile .bpx), skipping tools you already have.

#Exchanging markups (.bax)

Markups ▸ Export Markups… saves the document's markups (or just the selected ones) as a Bluebeam .bax, which Revu imports with Markups ▸ Import, or as a Cella file that keeps everything exactly. Markups ▸ Import Markups… (or dropping a .bax on the drawing) adds markups from either: they land on the same sheets, keep their authors, dates, status, replies and groups, and Undo takes them all back out. When a sheet is a different size (a new issue of the drawing), its markups go to the sheet with the same number.

#What doesn't come across

• Cella writes .bax files the way Revu writes markups and tool sets, but they have not yet been checked against Revu itself; if Revu refuses one, send it to us with the Revu version.
• Revu image stamps in a .bax come in as pictures you can move, and file attachments come in as they were (shown in the Markups List, not editable); both keep the picture or file exactly. A turned image stamp shows at the nearest quarter turn in Cella.
• Cut-outs travel both ways in the shape Revu is believed to use, but no Revu file with a cut-out has been checked yet: if a Revu area with openings reads as its full area in Cella, or a Cella cut-out measures uncut in Revu, send us the file.
• Revu's Studio Sessions and Studio Projects have no counterpart (an Atrium server does the sharing), and the hatch patterns of Revu's measurement tools come in as plain fills.

#Sharing and sync

Cella's Sync shares a project's drawings and everyone's markups live through an Atrium server: either one your IT runs on the firm's own server or cloud, or one Sorted Solution hosts for your firm at an address such as https://yourfirm.atrium.sortedsolution.com. Setting one up, inviting people, backups and the rest are in the IT guide, Atrium: the sync server for Cella; this section is about using it.

1. Sync ▸ Join Server…: the server's address and the invite code you were given, your name and email. The token is kept in your Keychain (on Windows encrypted for your account, on Linux in the keyring).
2. Open a document and Sync ▸ Connect Document to Project…: pick the project; if it doesn't have this document yet, Cella uploads it.

From then on every markup you make reaches the others in the project and theirs reach you; the status band shows ● project. Work offline freely: changes queue and send when the server is reachable (○ … offline · 3 pending).

What syncs: markups and their replies and statuses; sheets turned, moved, inserted, deleted or renamed (and sheet titles), with their markups going wherever their sheet goes; the custom columns, the sequences and where they have got to, the revision schedule, the bookmarks, and each sheet's scales, hyperlinks and Spaces. A sheet change arrives on everyone's copy as it is made, and their sheets list and thumbnails follow. ⌘Z undoes a sheet change of yours for everyone too: the sheet turns or moves back, a deleted sheet comes back with its markups and their history, an inserted one goes again, and ⇧⌘Z does it again. Your ⌘Z history stays as sheets move, arrive or go, yours or someone else's: each step finds its sheet wherever it is now. If someone else deleted the sheet a step was for, that step is skipped and Cella says so ("Can't undo: that sheet was deleted by Sam."). A markup you are still drawing (an area or polyline half clicked out) when sheets move is dropped. If an inserted sheet can't be downloaded at once (the network dropped), Cella keeps trying, and its markups appear with it.

When two people change the same thing at once (both turn the same sheet, rename it, reorder the sheets, or edit the custom columns), the change that reaches the server last stands everywhere, and the person whose change was replaced is told: "Sam turned “A-101” at the same time as you; their turn stands. The sheets were reloaded." If someone uploads a newer issue of the document, sheet changes made on the older one aren't sent ("Your sheet change wasn't sent"): use Sync ▸ Update Sheets from Project, then make the change again. An older Atrium server keeps only markups: on one of those, sheets can't be changed while the document is synced (Cella says so), and an older Cella on any server syncs markups only.

• Who else is here: while a document is connected you see the people working in it: each person's pointer on the sheet, with their name in their colour, and a dashed outline round the markups they have selected. In the status band a circle with their initials shows each person who has the document open; click one to go to their sheet. View ▸ Show Collaborators hides it all.
• Sync ▸ Update Sheets from Project pulls a newer issue someone uploaded and slip-sheets it in.
• Sync ▸ Show Markup History… lists who changed the selected markup and when (Properties ▸ History shows the same with the local record).
• Sync ▸ Disconnect Document stops syncing this document; Forget This Mac's Servers (Forget This Computer's Servers) removes the tokens.

If a hosted server's subscription runs out, the server becomes read-only: Cella says so, your markups stay in your PDF, and nothing more is sent until it is renewed.

The server sees only markup data, sheet changes and document settings (columns, sequences, the revision schedule, bookmarks), the PDFs you choose to upload and pages you insert into a synced document. Without a server, share a file the usual way: the PDF carries every markup, comment, reply, status and its history.

#Profiles and settings

#Settings

Cella ▸ Settings… (⌘,; File ▸ Options… on Windows, File ▸ Settings… on Linux, Ctrl+,):

• Author name: written into every markup you make.
• Appearance: System, Light or Dark.
• Default scale: the scale new sheets start with.
• Autosave: Off, or every 1, 2, 5 or 10 minutes; see Troubleshooting and recovery.
• Reopen documents at launch, Open documents in tabs, Automatically check for updates.
• Profile and Firm profile: see below.
• Keyboard: Shortcuts…: change any command's keys; see Changing shortcuts.

Tool defaults (colours, widths, fonts) are remembered as you change them in the toolbar. Whether the Welcome window appears at launch is the checkbox on the Welcome window itself; Invert Drawing, Snap to Drawing and the Snap pull-down's checkboxes are remembered from their menus.

#Profiles

A profile is your setup in one file: your Tool Chest's tool sets, your stamps, custom columns, status values, layout (where the sheets and panels go), defaults (tool styles, autosave, the Welcome window, Invert Drawing), units (default scale and presets) and the keyboard shortcuts you changed. A firm makes one so everyone works the same way.

• File ▸ Profiles ▸ Export Profile… asks for the profile's name and your firm's, and whether to include your signatures' pictures (off unless you tick it: a profile is meant to be shared).
• Import Profile… shows what the file holds with a checkbox for each part; for tool sets, columns and keyboard shortcuts choose Replace (the profile's instead of yours) or Merge (yours stay, the profile's new ones are added; for a shortcut you both changed, the profile's). Before anything is replaced your current setup is saved as the profile Previous Settings, so you can switch back. It also reads a Revu profile (.bpx, with a drawing open): its tool sets, custom columns and Markups List layout, the rest listed as not carried (see What to do with your Revu files).
• Imported profiles are listed in File ▸ Profiles with the active one ticked; choose another to switch to it. Manage Profiles… saves the current setup as a new profile and duplicates, renames, deletes, activates and reveals them. Add Profile Columns to Document gives the open document the profile's custom columns it doesn't have yet.

A firm profile. In Settings, Firm profile ▸ Choose… picks a profile on the office's shared drive. Cella applies it then, and again at launch whenever the file has changed, so the office can push new tools: the firm's tool sets replace the ones of the same name, your own sets stay, columns and the firm's shortcuts are added (your other shortcut changes stay), and layout, defaults and status values follow the firm's. The active profile shows in Settings and on the Welcome window.

#Firm standards

A profile can carry the firm's standards: a style sheet so every seat marks up the same way. They cover each tool's look (colour, fill, width, opacity, line ends, cloud, font, size, bold, italic, alignment), the nine hot colours, the Subject and Status values (and whether other values are allowed), the default scale and depth unit, how measurements read (feet and inches to 1/16", millimetres…), whether authors are written as full names or initials, header & footer presets, the firm's stamps, legend templates, and the profile's tool sets.

Each item can be locked. A locked value is enforced: you see its control, but it is disabled and says "Set by <profile>" (in Properties, the options row under the toolbar and the tool palette's STYLE column); new markups take it whatever you pick. An unlocked value is just the firm's default, which you may change.

• Making them: File ▸ Profiles ▸ Manage Profiles…, select the profile, and use the Standards table under the list. Capture Current Defaults takes your Mac's tool styles, colours, status values, scale, author rule, stamps and last-used headers and legend into the standard; Edit… (or double-click) changes one item: for a tool's style, pick the tool and set its colour, width, font and so on with the same controls as the options row. Tick Locked for what every seat must follow. Changes are saved to the profile at once; export it or put it on the office drive as the firm profile.
• Using them: importing or switching to a profile that has standards (or the firm profile changing) applies them; Apply to This Mac in the Standards table does it by hand. Each launch puts locked values back. Settings shows Standards: <profile> and the Welcome window's profile line does too. A profile without standards leaves yours as they are.
• Apply to Document gives the open document the profile's custom columns and gives sheets without a scale the default scale. Subject and Status lists stay in the profile: a PDF has no place for them.
• Headers & Footers… and Insert Legend… offer the firm's presets and templates in a popup (locked: only those). With the stamps locked, Create Stamp is off: use the firm's stamps.
• Settings ▸ Author shown as chooses full name or initials, unless the standard locks it.

#Keyboard shortcuts

Help ▸ Keyboard Shortcuts (⌘/; Ctrl+/), or the ? at the right of the status band, lists every shortcut over the drawing, with a filter field; Esc closes it. The full Mac list is the appendix at the end of this guide.

Single-key tool shortcuts (V, R, T, ⇧⌥L…) work only while the drawing has the keyboard, never while you type in a field. ⌃Tab (Ctrl+Tab) moves the keyboard between the sheets, the drawing, Properties and the Markups List (⌃⇧Tab goes back); the panel that has it shows a blue ring round its heading. In the toolbar the arrow keys move between buttons and Space presses one. Every button and list is named for VoiceOver, Narrator and Orca.

#Changing shortcuts

The keys in this guide are the defaults. Cella ▸ Settings… ▸ Shortcuts… (or Customise… at the top of the shortcut list) lists every menu command and every tool, grouped as the menus are, with a search field. Click a command's shortcut and press the new keys; Esc cancels and Delete leaves the command without one. ↺ puts one command back, Restore All Defaults puts them all back, and nothing changes until you click OK: then the menus, the toolbar's tooltips, the tool buttons, the command palette and the shortcut list all show the new keys.

• A menu command's shortcut needs ⌘ or ⌃ (or is a function key such as F5). A tool's key is a single letter or digit, with ⇧ or ⌥ if you like, and works while the drawing has the keyboard.
• If another command already has the keys, the row names it in orange with a Reassign button; only Reassign moves the keys (the other command is then left without any).
• ⌘Q, ⌘W, ⌘H, ⌥⌘H and ⌘, can't be changed, and neither can the keys macOS keeps for itself (⌘Tab, ⌘Space, ⇧⌘3 and the other screenshot keys, ⌃ and the arrow keys…) or ⌃Tab, which moves between panels.
• Your changes travel in a profile (Export Profile…), and a firm profile can set them for everyone.

Changing shortcuts is on the Mac today; Windows and Linux follow.

#Windows and Linux keys

On Windows and Linux, Ctrl stands for ⌘ and Alt for ⌥: ⌘S is Ctrl+S, ⇧⌥L is Shift+Alt+L. These are the exceptions:

On Linux, Ctrl+Alt+T is left to the desktop (it opens a terminal), which is why the tool palette is Ctrl+Shift+T on Windows and Linux alike.

#Troubleshooting and recovery

#Saving can't lose your file

Save (⌘S) writes the PDF to a temporary file next to the original, reads it back to make sure it is a complete, valid PDF, and only then swaps it in. If anything goes wrong (the folder is read-only, the file is locked or open in another program, the disk is full, the copy doesn't read back the same) your file stays exactly as it was, the document stays open with your markups in it, and an alert says why: "Couldn't save “A-101.pdf”". Use File ▸ Save As… to put a copy somewhere else. While a save hasn't worked, Cella won't close the window or switch to another file of the set, so nothing is dropped on the way.

The first save of a session also keeps the original in the .cella folder next to the file (.cella/<file>.bak), and every save adds to a log of the markups there.

#Saving keeps signatures valid

When you save a file you opened from disk, Cella adds your changes to the end of the file and leaves everything that was already there exactly as it was, as Acrobat does. Saving is quick even on big sets, and a digitally signed drawing stays signed: the signature still covers exactly what was signed, and a reader that checks signatures shows it valid, with your markups as changes made after signing.

Saving an encrypted or damaged file rewrites the whole file instead, and so does changing the sheets of a signed file (rotating, moving, inserting, deleting, cropping or replacing them, flattening, headers and footers). Then Cella asks first: Save Anyway rewrites it (the signature is no longer valid), Save a Copy… saves your changes to a new file and leaves the signed one as it is, Cancel saves nothing.

Earlier versions stay inside the file until it is rewritten (Cella does that by itself every 25 saves, or when you choose File ▸ Compact File, but never to a signed file), so a markup or a sheet you deleted can still be found by PDF tools. To hand out a file without them, use Export Flattened Copy or Reduce File Size.

#Autosave and crash recovery

While a document has unsaved changes, Cella writes them every two minutes to a recovery copy, .cella/<file>.autosave.pdf next to the file (or, if that folder can't be written, in Cella's own application data folder). Your file itself is not touched. Saving, reverting or closing the document cleanly deletes the recovery copy.

If Cella ends unexpectedly, the next time you open that file, or start Cella, it asks "Recover unsaved changes from Today at 14:32?" Recover opens them as unsaved changes to the file (save to keep them); Discard deletes the recovery copy and opens the file as it is on disk. Choose how often under Settings ▸ Autosave: Off, or every 1, 2, 5 or 10 minutes. View-only Cella doesn't save, so it doesn't autosave either.

#Encrypted and protected PDFs

A PDF that is encrypted but opens without a password (RC4, AES-128 or AES-256, which is how most "owner password only" files come) opens normally, and a save writes it back encrypted with the same protection and permissions. If its permissions forbid adding or changing comments, Cella opens it read-only and tells you once: ask the sender for a copy without that restriction. A PDF that needs a password to open can't be opened yet; Cella says so, and the way round is an unprotected copy from whoever sent it.

#Read-only files and folders

A file you can't write to (locked in the Finder, read-only on a server, in a folder you can't write in) opens normally and you can mark it up, but Save says why it can't, before anything is written: "You don't have permission to save in the folder “Issued”". Use File ▸ Save As… to save a copy somewhere you can write. The recovery copy goes to Cella's own folder instead.

#Other things to try

• The keys don't pick tools. Tool keys only work while the drawing has the keyboard: click the drawing (or press ⌃Tab until it has the blue ring) and try again.
• Panels cover the drawing. Below 1280 points wide panels float over the drawing; click the pin at the top of a panel to dock it, or choose View ▸ Panels Overlay the Drawing ▸ Never.
• A measurement reads "No scale". Set the sheet's scale (Tools ▸ Set Scale…) or calibrate.
• A damaged file. A damaged list of annotations doesn't stop a file opening; if a file won't open at all, Cella says why. Send it to us with Help ▸ Report a Bug….

#Getting help

• Help ▸ Cella Help (⌘?; F1) opens this guide in its own window, with a search field and the contents at the side. Help ▸ Online Documentation opens the same guide on the website, where it may be newer.
• Help ▸ Report a Bug… (⌥⌘B; Ctrl+Alt+B) sends us a report: see Reporting a problem below.
• Help ▸ Check for Updates… (on the Mac, Cella ▸ Check for Updates…) looks for a newer version. The daily automatic check sends only the app's version, whether a trial or a license is active, and the system version, and can be turned off in Settings.

Cella keeps no account and sends no documents, markups or usage data anywhere, except a report you send yourself with Help ▸ Report a Bug…. Sync talks only to your firm's Atrium server.

#Reporting a problem

Help ▸ Report a Bug… (⌥⌘B on the Mac, Ctrl+Alt+B on Windows and Linux) opens a short form: the type (a bug, something that looks wrong, a feature request or a question), a one-line title, what happened, what you expected, the steps if you know them, and your email so we can reply. Three boxes choose what goes with it, and What is sent lists it exactly before you send:

• Include a screenshot (on): the window as it was just before the form opened, with a preview and Retake; on the Mac and Windows you can send the whole screen instead.
• Include diagnostics (on): Cella's version and license state (never your licence key), your computer's model, system version, displays, language and free disk space, your settings (not your name, and no folder paths), and for the open document its name, size, page count and sheet sizes, never its content, with the last 300 lines of its save log in the .cella folder; and the system's record of Cella's last crash, if there is one newer than your last report.
• Include this document (off): the PDF itself. Tick it only if you may share the drawing with us; we use it to find the bug and delete it after. Files over 200 MB can't be sent this way: say so in the report and we'll send you a link.

On the Mac, Send opens Mail with everything attached (if you use another mail app, the report is saved on your Desktop as a zip and an email opens for you to attach it to). On Windows and Linux the zip is saved on your Desktop and an email to support@sortedsol.com opens; Reveal shows the zip. A copy of every report stays on your computer: Help ▸ Previous Bug Reports lists them. If Cella crashed the last time it ran, it asks at the next start whether to send the crash report (Send, Not Now or Never Ask).

#Coming from Bluebeam Revu

If you have used Revu for years, most of Cella is where you expect it, and the PDFs go both ways: Revu's files open in Cella with their markups, and what Cella saves is read by Revu (see Working with Bluebeam files). This section is a map: what each Revu feature is called in Cella and where to find it, the keys, and what to do with your Revu files. Most of it needs a key or the trial; a view-only Cella views, searches and prints (see One product, one key).

#Revu to Cella, feature by feature

#Keys

Cella took Revu's single-letter tool keys, so a tool's key is the same: press it while the drawing has the keyboard. The Mac and the Windows and Linux keys are the same letters; the measuring tools use ⇧⌥ on the Mac and Shift+Alt on Windows and Linux.

The menu keys are the Mac's usual ones, with Ctrl for ⌘ on Windows and Linux, except where the table says otherwise. The ones you will reach for:

If a key isn't the one you are used to, change it: Cella ▸ Settings… ▸ Shortcuts… lists every menu command and tool, and Help ▸ Keyboard Shortcuts (⌘/) shows the keys you have now (see Changing shortcuts; changing keys is on the Mac today, Windows and Linux follow). The whole list is the appendix.

#What to do with your Revu files

• Drawings with markups. Open them. Revu's markups, measurements, scales, replies, statuses, groups and custom column values are read and kept, and a markup you don't touch is saved as it was.
• Tool sets. In Revu, Tool Chest ▸ Manage Tool Sets ▸ Export makes a .btx. In Cella choose Tools ▸ Import Bluebeam Tool Set… (or Import… in Tools ▸ Manage Tool Chest…). Do this for each set, including your punch keys.
• Profiles. Export the profile from Revu (a .bpx), open any drawing in Cella and choose File ▸ Profiles ▸ Import Profile… with the .bpx. Cella reads its tool sets (each its own set), its custom columns (text, number, choice list, checkmark and formula columns; a date column becomes text, and a formula Cella can't read is kept as a text column with a note) and its Markups List layout (saved as the view "Revu: profile name"), and the import sheet shows them with a checkbox each before anything is installed. It also lists what is not carried: toolbars, keyboard shortcuts, Studio settings and stamps. Cella reads .bpx files as Revu is believed to write them, not yet checked against a real export: if yours doesn't come in as it should, send it to us. To take only the tool sets, give the .bpx to Tools ▸ Import Bluebeam Tool Set…. Then save the setup with File ▸ Profiles ▸ Export Profile… so the office can share it, or put it on the shared drive as the firm profile (Profiles and settings).
• Custom columns. The columns on your markups are read from the PDF. Markups List ⋯ ▸ Custom Columns… shows them, and File ▸ Set ▸ Apply Columns to Set… gives every file of a set the same ones.
• Exchanging markups. Markups ▸ Export Markups… writes a .bax that Revu imports (Markups ▸ Import in Revu), and Markups ▸ Import Markups… reads one; the .bax Cella writes has not yet been checked against Revu itself.
• Cut-outs. An area's openings are read and written in the shape Revu is believed to use, not yet checked against a Revu file with a cut-out. Check the first area you open or send.
• Studio Sessions and Projects. These have no counterpart: a PDF you have from them opens like any other, and sharing between people is done with an Atrium server (Sharing and sync).

#What Cella doesn't do (yet)

Cella is not a copy of Revu. What it does not do, or has not yet been checked on, is listed in What's not there yet and, for Bluebeam files, under What doesn't come across.

#What's not there yet

• The Windows and Linux versions have not yet been run on those systems. They carry the same features as the Mac, built and tested but untested until that first run, and the Windows installer has not been run either. On those two, Visual Search has a minimal control, Project Tools show read-only, and a picture dropped on the Sheets strip is not taken.
• Form calculations, formats, validation and date pickers work for the standard Acrobat ones; custom form scripts (pop-up messages, your own code) don't run, and you can't create or edit form fields.
• Edit Text writes a letter the drawing's font lacks in Liberation Sans or the matching serif or monospace face rather than the original typeface; a paragraph that grows runs over what is below it; it doesn't edit blocks placed more than once or nested in other blocks, Type 3 fonts or vertical text, and it is refused on a document synced through Atrium and in Split View's second pane. Recognize Text (OCR) on Linux needs Tesseract installed (see Search); a placed signature is a picture (see Signatures).
• Redaction has the limits listed under Redaction (Type 1 fonts, letters that only just touch a mark, lines much wider than a mark): check the copy before you send it.
• Cut-outs show open in every viewer and are written and read in the shape Revu is believed to use, not yet checked against a Revu file with a cut-out.
• The .bax Cella writes has not been checked against Revu itself, and file attachments from a .bax can't be edited in Cella.
• Scales, scale regions, hyperlinks and Spaces sync only through an up-to-date Atrium; with an older one they stay on each copy.
• Cropping and resizing sync only through an up-to-date Atrium; with an older one a synced document refuses them. When two people resize the same sheet at once, the later one stands. An undo of an older link or Space step after someone else changed the same one puts your version back. Pages inserted while you are offline wait on disk until they upload, up to 64 MB of them (past that it says so).
• Export to Excel has not yet been opened in Excel itself; it is read back and checked in tests.
• Export Markups to DXF has not yet been opened in AutoCAD or another CAD program; its files are read back and checked in tests. Arrowheads, fills, count symbols and stamp pictures are not carried.
• Export PDF/A-2b Copy passes the veraPDF validator on our test sets, but none of them drew in CMYK; a drawing in CMYK colour or with a font Cella has no replacement for may need attention.
• Sheets from CAD exports with thousands of fonts and pictures open faster and lighter than they did: a synthetic 10-sheet set now views in about 1.3–1.4 GB of memory (now and then more), and Cella reads the whole file to open it.

#Cella on the iPad

Cella for the iPad opens the same PDFs and writes the same markups as the Mac, and the files go back and forth without conversion. This chapter covers only what differs on the iPad; the tools, measuring, the Markups List and the Tool Chest work as described in the rest of this guide. Keys on the iPad are for a Magic Keyboard.

Opening drawings. Cella shows the Home when it starts: a Recent row, the sample set, and the licence status. Open brings up the Files browser, so a drawing can come from On My iPad, iCloud Drive or any provider Files shows (Dropbox, OneDrive and so on). You can also open a PDF from another app with Open in Cella, or tap Share ▸ Cella in Files or Mail. Cella keeps the drawing where it is and saves through Files, so an iCloud file stays in iCloud. A .bax opened this way goes into the drawing that is open; a .btx goes into the Tool Chest. Open the sample drawing on the Home opens A-101, the clinic floor plan used for the pictures in this guide.

The trial and buying. The 14-day free trial starts the first time you open Cella, with no sign-up. The pill at the top of a document counts the days. When it ends Cella is view only, as on the Mac: you can open, read, search and print, and the Cella sheet explains how to carry on. Two ways to buy: - Buy Cella… (on the Home, and on the sheet) is the App Store purchase: one payment through your Apple account. - Enter License Key… takes a key you already have, including one bought for another platform. One key covers one computer (Mac, Windows or Linux) and one iPad. Restore Purchases, on the licence screen, brings back an App Store purchase on a new or erased iPad. Deactivate This Device… frees the iPad's place on a key.

Touch and Apple Pencil. - One finger draws with the tool you have chosen. With Select it selects what it touches and pans the sheet when it touches nothing. - Two fingers pan and pinch, about the point between them. A double-tap fits the sheet. - A long press opens the menu a right-click gives on the Mac. Long-press a tool in the palette for its variants. - The Pencil draws with pressure on the Pen, and a resting palm is ignored while the Pencil is down. - A double-tap on the Pencil's side returns to your last tool, as the Pencil settings say. Where those settings say "switch to eraser", Cella chooses Select for now, since it has no eraser tool.

The panels. The sidebar at the left has Sheets, Search, Layers, Bookmarks, Markups List and Tool Chest tabs, as the Mac's sidebar does; tap a sheet to go to it. The tool palette floats over the drawing: drag it to any edge and it stays there. The options bar above the drawing shows the active tool's colour, line, fill and opacity. Properties opens from the selection or from the options bar and changes every selected markup at once.

Printing and sharing. Print uses AirPrint and prints the sheet with its markups. Share offers the PDF, Save a Copy… and the exports (Excel, DXF, PDF/A, flattened PDF). While the trial has ended and no key is entered, the exports are greyed; Share PDF, Save a Copy and Print stay.

Autosave and recovery. Cella saves a copy every two minutes into its own storage, never beside your drawing. If the iPad runs out of power or Cella is closed with changes unsaved, the Home offers Recover unsaved changes… or Discard the next time.

What is not on the iPad yet. Settings (the Mac's Settings window), importing a Profile, signing a document with a certificate, the Print sheet's page ranges, scale and tiling, the Pencil as an eraser, and one window per document (Stage Manager) are coming. Everything in What's not there yet applies here too.

#Appendix: Keyboard shortcuts

Help ▸ Keyboard Shortcuts (⌘/) shows this list over the drawing, with a filter field. These are the default keys: Cella ▸ Settings… ▸ Shortcuts… changes them, and the list then shows yours. Single-key tool shortcuts work while the drawing has the keyboard, never while you type in a field. On Windows and Linux, Ctrl stands for ⌘ and Alt for ⌥. Once the free trial has ended, only Select and Pan work until you buy Cella.

#Navigation

#View

#Tools

#Markup

#Sheets

#Edit

#Panels

#File

#App and Window