v0.91.1 Your Own Data

A script can read and write its own data files now. A rhythm chart, a dialogue tree, a table of enemy stats — anything you would rather author as JSON than as a Lua table — is a file under Assets/, and a script gets it in one call.

Data files, in and out

json.encode and json.decode have been here since v0.20.0, but a script had no way to open a file: assets.getFile answers a path, which is what a model or a material wants and nothing a script can read. So a chart authored outside the game had to be rewritten as Lua, or pushed through save.* a kilobyte at a time. Four calls close that gap:

local chart, why = assets.readJson("charts/neon.json")
if not chart then return log("no chart: " .. why) end
for _, note in ipairs(chart.notes) do
  spawnNote(note.t, note.lane)
end

• assets.readJson(path) — a JSON file decoded straight to a Lua value, by json.decode's rules: objects are tables, arrays are 1-based lists that stay lists on the way back out, null is nil.
• assets.writeJson(path, value [, { pretty = true }]) — the reverse. pretty indents it for a person, or for a git diff.
• assets.readText(path) / assets.writeText(path, text) — the same for any text file, when the format is your own.

Writing back is the half that makes a chart editor a scene in your game rather than a tool outside it: record the hits, call assets.writeJson, and the file it wrote is one the Asset Browser shows, git diffs and the export ships. A write creates the folders on the way.

Every one of them answers value, why rather than raising — a data file is content, and a file that is missing, not text, or not JSON is a message in the Console and a nil the script can handle, never an error that stops the script loading. Paths are relative to Assets/ and stay inside it, the same rule assets.getFile follows; a path that would leave the project is refused and says so. The same calls work in an exported build and in a browser, where a read comes from the bundle and a write lands in the page's own storage.