From SuperTux

Contents 1 Introduction 2 Example 3 Format 3.1 (sprite) block 3.2 (action) block 4 Adding Own Sprites / Testing 4.1 Sprite Editor

[edit] Introduction

Most animated images you see in supertux are sprites. Sprite definitions are defined in individual files that end in ".sprite", e.g. "data/images/creatures/snowball.sprite", and follow S-expr syntax.

[edit] Example

(supertux-sprite
  (action
    (name "left")
    (hitbox 2 4 31.8 31.8)
    (images "left-0.png"
            "left-1.png"
            "left-2.png")
  )
  (action
    (name "right")
    (hitbox 2 4 31.8 31.8)
    (mirror-action "left")
  )
  (action
    (name "squished-left")
    (hitbox 1 -19 31.8 31.8)
    (images "squished-left.png")
  )
  (action
    (name "squished-right")
    (hitbox 1 -19 31.8 31.8)
    (mirror-action "squished-left")
  )
)

[edit] Format

Let's look at the sprite "snowball":

A sprite consists of a set of actions. An action is simply an animation composed from several images. The engine can render a sprite and change it's currently displayed action. The snowball sprite, for example, contains 4 actions named "left", "right", "squished-left" and "squished-right".

Additionally you can define animation speed (fps <n>) and a hitbox (hitbox <x> <y> <w> <h>).

The hitbox offset indicates where the "origin" of the sprite is: If the engine draws a sprite at position 50,50 then <x> will be substracted from the x coordinate and <y> will be substraced from the y-coordinate. The hitbox size will get read by most sprites' gamecode to set the width and height of an imaginary rectangle that defines what parts of a sprite are solid.

[edit] (sprite) block

The sprite description file is S-expr based. A sprite description starts with a (sprite) list, It should then contain a name entry (name "myname") and then several (action) entries (at least 1).

[edit] (action) block

The action block contains then the name of an action (name "myaction") can optionally contain an (hitbox <x> <y> <w> <h>) block. It's also possible to add an (fps number) block to define the number of frames played per second. Finnaly comes a list of (images) or the '(mirror-action "actionname") keyword which will take an already defined action and flip all it's images vertically.

[edit] Adding Own Sprites / Testing

You can easily add your own sprites by creating a custom .sprite file and placing it somewhere appropriate, e.g. "data/creatures/<name>/<name>.sprite" for badguys or "data/objects/<name>/<name>.sprite" for game objects. Now you probably want to test your sprite. This is easily possible from the game Console (example for data/images/creatures/yeti/yeti.sprite):

 testsprite<-FloatingImage("images/creatures/yeti/yeti.sprite")
 testsprite.fade_in(1)
 testsprite.set_action("run-left")

To remove the sprite from your screen, use

 testsprite<-null

An alternative would be creating ScriptedObjects in the leveleditor and selecting your spritefile

[edit] Sprite Editor

A Python/GTK-based sprite editor, named GSprite, is currently under development. Such an editor will have a graphical interface, and be able to add, remove, and edit individual actions, but will require Python, GTK, and PyGTK libraries as dependencies.