spine

[dependencies.spine_tiny]
git = "http://github.com/tomaka/spine-rs"

extern crate spine;

Parses a Spine document and calculates what needs to be drawn.

You can find an example here

Step 1: loading the document

Call skeleton::Skeleton::from_reader to parse the content of a document.

This function returns an Err if the document is not valid JSON or if something is not recognized in it.

let file = File::open(&Path::new("skeleton.json")).unwrap();
let skeleton = spine::skeleton::Skeleton::from_reader(file).unwrap();

Step 2: preparing for drawing

You can retrieve the list of animations and skins provided a document:

let skins = skeleton.get_skins_names();
let animations = skeleton.get_animations_names();

You can also get a list of the names of all the sprites that can possibly be drawn by this Spine animation.

let sprites = skeleton.get_attachments_names();

Note that the names do not necessarily match file names. They are the same names that you have in the Spine editor. It is your job to turn these resource names into file names if necessary.

Step 3: animating

To run an animation, you first need to call skeleton.get_animated_skin to get a SkinAnimation.

You then have 2 methods to get the sprites you need to draw:

• directly call animation.interpolate for a given time
• use a built-in AnimationIter iterator by calling animation.run() to run the animation with a constant period

Both methods returns a Sprites iterator over the Sprites do be drawn.

let animation = skeleton.get_animated_skin("default", Some("walk")).unwrap();

// either use `interpolate`
let sprites = animation.interpolate(0.3).unwrap();
// or use the iterator
let sprites = animation
              .run(0.1)  // iterator that interpolates sprites every 0.1s
              .nth(3);   // get the 3rd item generated when time = 0.3

The result contains an iterator over the sprites that need to be drawn with the skeleton::SRT (scale, rotate, translate)). The srt supposes that each sprite would cover the whole viewport (ie. drawn from (-1, -1) to (1, 1)). You can convert it to a premultiplied matrix using srt.to_matrix3() or srt.to_matrix4 ; if you want to apply your own matrix C over the one returned M, you need to call C * M.

for sprite in animation.interpolate(0.3).unwrap() {
    let texture = textures_list.get(&&*sprite.attachment).unwrap();
    draw(texture, &sprite.srt, &sprite.color);
}