Slides

A slide is a single cell on the 2D canvas. It carries a title, a position, and a stack of positioned elements, plus a few properties that control how it scrolls.

Anatomy

Each slide is authored as a .slide.json file (JSON5 on the .json extension). At minimum it has a title and a list of elements; its grid position is set from the deck manifest. See Slide format for the full field list.

Scroll range

A slide's scroll_range is how far the reader scrolls from top to bottom. It can be a fixed number, or "auto" (the default) for content-driven height — the slide is exactly as tall as its content needs. An explicit 0 pins the slide static: it never scrolls, even when its content is taller than the viewport. Animation keyframes are expressed in scroll-position units within this range.

Snap positions

snap_positions are scroll offsets the view eases to as the reader scrolls, so a slide can rest on meaningful moments rather than anywhere. Readers can toggle snapping on or off while viewing — see Navigation & shortcuts.

Other controls

• font_scale multiplies the slide's text size, for tuning density independently per slide.
• reverse flips the scroll direction so the thumb starts at the bottom and rises as the reader advances — natural for bottom-up content.