Image formats supported in Endless Sky

The file formats currently supported for simple images are .png and .jpg/.jpeg/.jpe. Since v. 0.10.15, you can also use .avif/.avifs files to store all frames of an animation. In this case, you should only have one file matching the sprite name.

File names

The general naming pattern of sprites used in Endless Sky looks like this:

<sprite-name><blending-mode><frame-number><swizzle-mask-flag><size>.<extension>

• <sprite-name> is the common stem of all filenames that are combined into a single in-game sprite. This is the identifier that should be used when referencing the sprite in game data.

• <blending-mode> is a single-character specifier for transparency handling. Can be omitted if there is no frame number in the name. See the Blending Modes page for details.

• <frame-number> is the index (starting from 0) of the sprite frame this file contains. Can be omitted if the sprite has only one frame.

• <swizzle-mask-flag> is a @sw string. If present, it indicates that this file is not normal sprite data, but a swizzle mask.

• <size> can be omitted, or one of the following:

  • @2x, which means the file is a high-resolution sprite and should be used when a high-DPI display is detected by the game or main zoom factor is high enough,
  • @1x, indicating that it's important to keep the sprite in its original resolution (for example when the sprite represents a UI element) even when sprite reduction is enabled (v. 0.10.17).

• <extension> is one of the supported image format extensions (listed above).