cl-aseprite

System Information

Definition Index

• CL-ASEPRITE

  • ASEPRITE
  • ASE

  NOTE: this software is of alpha quality, and the API is subject to change.

  cl-aseprite is a high-performance Common Lisp library for parsing .aseprite files created with Aseprite and LibreSprite programs into meaningful Lisp structures.

  Aseprite is a proprietary image editor designed for pixel art drawing and animation. It was used in the development of several notable games such as Celeste, Loop Hero, and many others (source: Wikipedia).

  LibreSprite is a free and open source fork of Aseprite created after its license changed from GPLv2 to proprietary in 2016.

  Key part of the library is LOAD-SPRITE function, which returns SPRITE structure, which in turn contains lists of TAG and LAYER structures with latter having an array of CEL structures. See Aseprite docs for details on those entities.

  In most cases, CEL's DATA field contains an array of 32-bit ABGR pixel data, so to convert it to image just copy it using CFFI into proper container, e.g. to the result of call to al_lock_bitmap when using cl-liballegro.

  • EXTERNAL STRUCTURE

    CEL

    Source

    Representation of cel.

    • DURATION: duration in milliseconds
    • X: x position of cel data
    • Y: y position of cel data
    • OPACITY: opacity level
    • Z-INDEX: z-index
    • TYPE: one of :IMAGE, :LINKED or :TILEMAP
    • USER-DATA: user data string
    • WIDTH: width in pixels (for :IMAGE type) or in tiles (for :TILEMAP type)
    • HEIGHT: height in pixels (for :IMAGE type) or in tiles (for :TILEMAP type)
    • DATA: raw data, only for :IMAGE and :TILEMAP types
    • FRAME-POSITION: frame position to link with (only for :LINKED type)
    • ID-BITMASK: bitmask for tile ID (only for :TILEMAP type)
    • X-FLIP-BITMASK: bitmask for X flip (only for :TILEMAP type)
    • Y-FLIP-BITMASK: bitmask for Y flip (only for :TILEMAP type)
    • DIAGONAL-FLIP-BITMASK: bitmask for diagonal flip (only for :TILEMAP type)
  • EXTERNAL STRUCTURE

    LAYER

    Source

    Representation of layer.

    • VISIBLEP: whether layer is visible
    • BACKGROUNDP: whether layer is background layer
    • CONTINUOUSP: whether layer is continuous (prefers linked cels)
    • REFERENCEP: whether layer is reference layer
    • TYPE: one of :IMAGE, :GROUP or :TILEMAP
    • CHILD-LEVEL: relationship with next layer in layers list, see here
    • BLEND-MODE: keyword indicating blend mode
    • OPACITY: layer opacity. only valid if SPRITE-HAS-OPACITY-P is T
    • TILESET-INDEX: only for :TILEMAP type
    • USER-DATA: user data string
    • CELS: array of CELs, indices correspond to frame numbers
  • EXTERNAL STRUCTURE

    SPRITE

    Source

    Representation of sprite.

    • WIDTH: width in pixels
    • HEIGHT: height in pixels
    • COLOR-DEPTH: color depth in bits per pixel, could be 32 (ABGR), 16 (grayscale) or 8 (indexed)
    • COLOR-PROFILE: :SRGB or NIL (corresponding to "None")
    • HAS-OPACITY-P: whether there is opaque color
    • TRANSPARENT-INDEX: palette entry index for transparent color (only for indexed sprites)
    • COLORS: number of colors
    • PALETTE: palette as an array of packed ABGR values
    • PIXEL-RATIO: pixel width/pixel height
    • USER-DATA: user data string
    • FRAMES: number of frames in each layer
    • LAYERS: plist of sprite LAYERs in reversed order
    • TAGS: plist of frame TAGs
  • EXTERNAL STRUCTURE

    TAG

    Source

    Representation of tag.

    • FIRST-FRAME: index of first tagged frame
    • LAST-FRAME: index of last tagged frame
    • DIRECTION: one of :FORWARD, :REVERSE, :PING-PONG or :PING-PONG-REVERSE
    • REPEAT: repeat N times. 0 means infinite, 1 once etc.
    • USER-DATA: user data string
  • EXTERNAL FUNCTION

    LOAD-SPRITE

    • FILESPEC

    Source

    Loads Aseprite file from given FILESPEC, either path or binary stream.

    See SPRITE.