#Assets

Your Asset library holds the files your games use. Assets belong to your workspace, so every project can use them.

#Upload an asset

  1. Open Upload asset (or Asset library → Upload asset).
  2. Drop the files for one asset, or browse for them. The kind is detected from the set.
  3. Check the name and the alias prefix; the form shows the aliases it creates.
  4. Optionally pick a requirement to check against, and a project to add it to.
  5. Tick I have the right to use these files in my games.
  6. Choose Add to library. The files upload straight to storage, then the server checks them and shows any warnings.

If the files can't be used (for example an atlas page is missing), nothing is kept and the message says why.

#Upload rights

Every upload (assets, components, and uploads from the editor) asks you to confirm that you have the right to use the files. The confirmation is kept with each asset: who confirmed it, when, and which wording they saw. Once you've ticked it, it stays ticked on every upload screen until you close the browser. If the wording changes, you're asked again. An upload without it is refused.

#Asset kinds

Kind Files Aliases
Image one PNG, JPG, WebP, GIF, AVIF or SVG prefix
Spritesheet .json (TexturePacker) plus its page images prefix
Spine .json or .skel, .atlas, and the atlas pages prefixSkeleton, prefixAtlas
Bitmap font .fnt (text or XML) plus its page images prefix
Video WebM or MP4 prefix
Audio MP3, OGG or WAV prefix
Font one TTF, OTF, WOFF or WOFF2 prefix

#Fonts

Upload a font file (TTF, OTF, WOFF or WOFF2) like any other asset. When the upload finishes, the font is checked by its contents, not its extension, and its family name (and style, such as Bold) is read from the font itself and shown in the library. The preview draws a sample line in the font. Collections (.ttc) aren't supported; upload each font on its own.

Text uses a font by its alias, and builds include the font file with the game. Fonts are different from bitmap fonts: a bitmap font is a .fnt with images and draws only the characters it has, while a font file scales to any size and covers its whole character set.

Aliases are unique in your library. Scenes refer to assets by alias, so changing a file means uploading it under the same alias after deleting the old asset.

#Preview

Choose Preview on a card. Spine animations play live, with the animation list, play and pause, loop, speed and skins. Bitmap fonts render a sample of their own characters. Images, spritesheets, video and audio use the browser's players.

#Requirements

A requirement is a set of checks an asset should pass, such as "Slot game logo": a Spine skeleton with the animations intro and loop, the slot numbers_holder, and under 2 MB. Templates use requirements to describe the assets you swap in. Pick one when uploading, or in the preview, to see which checks pass. A failed check doesn't stop the upload.

#Export Spine 4.3

The engine runs Spine 4.3. Skeletons exported from another version get a warning ("Exported with Spine 4.1.24; the runtime is 4.3") and may not play correctly.

  1. Open the project in Spine 4.3 or later.
  2. Export → JSON (or binary), with Pack set to create an atlas.
  3. Upload the .json or .skel, the .atlas and every page image together.

#Delete an asset

Open its preview and choose Delete asset…. An asset a project still uses can't be deleted; the dialog names the projects. Deleting frees its storage.

#Storage

The meter under the library shows assets and builds against your plan's quota. See Plans and billing.