Bakes and the timeline

The Timeline automatically keeps committed simulation states. Run and Step append frames; scrubbing restores a recorded state without recalculating it. The download icon beside Timeline saves the current timeline as a .hylebake. No account is needed to play, scrub, or download a bake.

At the latest frame, Undo reverts the last recorded simulation step or cell edit so you can continue from the preceding state. Redo restores it without recalculating. A new step or cell edit replaces the undone future. Scrubbing alone does not discard redo frames. Undo and Redo are disabled during computation or loading and are unavailable in read-only bakes. A continuous brush stroke may produce several recorded edits, so undoing it can take more than one click.

The size includes frames held for Redo. Downloads contain only the active timeline; redo frames are excluded. New edits release discarded redo storage.

Opening and editing

Use File → Open bake… to open a local bake in a separate tab (a separate window in the native app). It opens as Read-only bake: you can play its frames, move the camera, inspect cells, and change viewing options. Source, cells, solver precision, and recorded frames cannot be changed in this document.

Use Fork & save to turn the displayed state into a private project on your profile. Sign in first. The new project’s initial cells come from the visible frame; earlier and later frames stay in the original bake. Published simulations and their bakes remain unchanged.

An editable project’s past frames are also read-only. Scrub back to the latest frame to continue developing, or fork from the displayed frame to develop a separate future. There is no take selector or separate recording-management panel.

File → Open project… opens an editable .hyleproject package or a single .hyle source file. Download a project through File → Download project (Save project file… in the native app). A project package contains source, pinned dependency source, and the starting-world recipe; it does not contain the timeline or automatically capture the live viewport. To retain the displayed scene as a new project’s starting world, fork from that state first. Guests can download the timeline bake to preserve it without creating a profile draft.

Playback and limits

The scrubber updates while dragging. One restore runs at a time; newer positions replace the pending target. The last completed frame remains visible until its replacement is ready. Loading feedback is delayed and occupies reserved space.

Download before closing: the timeline cache is temporary. If its 512 MiB limit is reached, Studio stops instead of silently deleting frames. Download the bake, then start a new project or fork from the current state. Compiling or changing solver replaces the timeline after a warning; download it first to preserve it.

The .hylebake format contains simulation states and the source needed to view them with a compatible compiler. Camera movement is not recorded. It is not a rendered video. Blender, USD, OpenVDB, and rendered-video exports are not yet implemented.