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Opening projects

Every way into an existing project: the Open dialog, the Recent list, dragging a file onto the window, double-clicking in your file manager, and the command line.

File ▸ Open… brings up your system's browse dialog with two filters: Celas Studio Project for .cls files, and SVG Drawing. A project opens into its own document tab; an SVG is not a project, so it opens as a fresh untitled document with the drawing imported into it.

If the tab you are sitting on is untitled and untouched, it is replaced rather than joined: you do not collect empty documents. A project that is already open in a tab is simply brought forward, keeping the zoom and pan you left it at, while a freshly loaded one is fitted to the canvas.

CtrlO Open
CtrlN New project
CtrlW Close the current document

Recent projects

The Home window opens on its Recent tab, showing a card for each project you last worked on: the preview stored in the file, the file name, and the folder it lives in. Click a card to open it.

The list holds up to 16 projects, most recent first, and is written to disk the moment it changes. Hovering a card reveals a small x in its corner that takes the project off the list without touching the file on disk. A project whose file has gone missing shows its name in dull red and will not open.

A card that does not open tells you which of the two problems it hit. A file that is no longer where the list remembers it reads that it could not be found and may have been moved, renamed or deleted; a file that is there but cannot be read reads that it may be damaged or written by a newer version of Celas Studio. The same two messages appear when the file comes from Open, a drop or the command line, so a project that will not open is never a silent dead click.

Only projects are remembered. An SVG you opened is never added, because opening it again would build a new document from scratch rather than reopen anything.

The Home window Recent tab with project cards, one hovered to show its remove badge.
You can also reach Open from the Home window's Open… pill, and from the three cards (Home, New Project and Open…) that fill the viewport when no document is open.

Dragging files onto the window

Dropping a file on Celas Studio does one of two things, and where you drop it decides which.

Dropped fileOn the canvasAnywhere else in the window
.cls projectMerged into the current scene as a groupOpened as its own document
.svg drawingImported into the current sceneOpened as a new untitled project
Image, video, audio, PSDImported into the current sceneImported into the current scene

Media has no meaning as a document of its own, so it always imports wherever it lands. With no document open at all, only a .cls or an SVG is accepted: there is no scene for anything else to land in.

Dropping a .cls onto the canvas merges it into the project you are in; it does not open it. If you meant to open it, drop it on a panel or the title bar instead. See Merging another project.

Opening from your file manager

On Windows .cls files are registered as Celas Studio Project, so double-clicking a project in Explorer opens it, starting Celas Studio first if it is not already running. Celas Studio claims the extension itself on every launch, for the current user only, so a Steam or portable copy that never ran an installer gets the association too. On macOS the application bundle declares .cls as its own document type, so Finder shows the project icon and Open With behaves as you would expect.

The .cls extension is not ours alone: LaTeX class files and some Visual Basic tooling use it too. Celas Studio never takes the default away from whichever app already holds it; it adds itself to Open with, and only becomes the default if nothing else has claimed the extension or you set it yourself in Windows Settings.

On Linux there is no file association: start Celas Studio and open the project from inside the app, or pass it on the command line.

The command line

Celas Studio accepts one argument, a path to a project:

  • celasstudio.exe "D:\Work\walk-cycle.cls"

The project opens and is added to Recent, and the Home window is skipped so you land straight on the canvas. Any further paths are ignored.

Two switches exist, both for the Windows file association, and both do their work and exit without opening a window. They are there for deployment and support cases where the association has to be fixed without starting the app:

SwitchWhat it does
--register-file-typesClaims .cls for the current user, the same write the app makes at startup
--unregister-file-typesRemoves the entries, but only the ones still pointing at this copy of Celas Studio

There is nothing else: no --help, no --version, nothing to render a project from a script.

The Home window otherwise appears at startup unless you turn off Show at startup at the bottom of it.