pdf-next

pdf-next by machine-made.

You write in one window and read in another. pdf-next is the other window.

Point it at the PDF your LaTeX or Typst build writes, or at the Markdown file you are editing, and it redraws every time the file changes, on the same page, at the same zoom, in the same spot. You stop switching windows to press reload. Then it gets out of the way: no ribbon, no account, nothing to sign in to, and nothing downloaded after you install it.

It opens PDFs, Markdown and images (.png, .jpg, .webp, .avif) on Windows, macOS and Linux. It is the desktop sibling of vscode-pdf Next and draws pages the same way, with Mozilla PDF.js ([email protected]) in a worker thread.

A quick tour

It follows your file

• Rebuild and look. Watching is on by default. Save or rebuild and the view updates within a second, keeping your page, scroll position and zoom. The View menu sets how often it looks (1 s, 2 s, 3 s, or off). If the build deletes the file first, the last page stays on screen with a red dot until the new file lands.
• See what the rebuild changed. In Markdown the changed blocks light up for a few seconds; in a PDF the new words do, and thin ticks along the right edge show where on the whole document the changes are. The ticks stay, faint, until the next build; click one to go there, or press . and , for the next and previous change. Pages that did not change get nothing, and a page the build added is marked whole. A long thesis is compared page by page in the background, so the reload is as quick as before.
• It never shows a half-written file. A build takes hundreds of milliseconds to write a PDF, and a naive viewer reloads the half it has. pdf-next waits until the file is whole: on Windows the writer holds a lock, so opening it fails until it is done; on macOS and Linux it also checks for the PDF's closing %%EOF. If the file is not ready, it tries again next tick.
• Your build can always write. The page is kept in memory and the file is closed after reading, so you can overwrite, replace or delete it while it is on screen.
• Sharp on any screen. Pages redraw when you move the window to a display with a different scale, and deep zoom only draws what you can see.

The window fits the page

• It opens at the size of what you opened. A paper comes up at 100% in a window the size of its page, centred; a wide figure gets a wide window. A figure bigger than the screen, such as a plot saved at 400 dpi, is scaled down until it fits whole. A page taller than the monitor fills the screen's height and scrolls. This only happens when you open a file: rebuilds and tab switches never move your window.
• Dock it to half the screen with the Window menu (a small picker laid out like the screen) or Ctrl+Shift+← / → / ↑ / ↓, so the document takes one half and your editor the other. Docked, it fits the width, so the text stays readable. The centre of the picker, Ctrl+Shift+Enter, or the same edge again undocks.
• Or bring the window to the content with Ctrl+Shift+F: set a figure to the size you want and the window closes in on it, edge to edge. It stays on, so zooming moves the window with you, up to the size of your screen. Picking a fit from the zoom menu turns it off.
• Full screen with F11, or from the Window menu. F11 again comes back.
• Present with F5: full screen, no toolbar, one page at a time fitted to the screen, on black. ← / →, PageUp / PageDown (what a presentation clicker sends), Space, Home and End move through the pages; Esc comes back to the view, zoom and page you had. A Markdown file is shown as its A4 pages. The outline steps aside while you present, Alt+← after following a link goes back to the slide you came from, and switching to another tab ends the presentation.

This is the beginning of the README. Read the rest at the original. Read the full README ↗