A simple 2d sprite animation plugin for the Bevy game engine.
Anyone is welcome to make suggestion and corrections to this repository, typographic and otherwise!
This is more or less a copy of Aarthificial's Reanimator for Unity but for Bevy of course.
Here is a video explaining how the example works. Here is a video going over what is new in 0.4
subject to change with feedback
0.3 = Bevy 0.7 avalable as 0.7 branch
0.3.1 = Bevy 0.8 avalable as 0.8 branch
0.3.1 = Bevy 0.10 avalable as 0.10 branch
0.3.2 = Bevy 0.11 avalable as master branch
0.4 = Bevy 0.11 avalable as v0.4 branch
the usize is the max nodes a single path can take this is to stop loops from locking up frames indefinitly
fn main() {
App::build()
.add_plugin(AnimationPlugin::<10>)
.add_startup_system(add_nodes.system())
.add_startup_system(add_animator.system())
.add_system(update_animator)
.add_system(read_animator)
// registure any custom nodes so thay can be loaded
// these nodes should reflect LoadNode inorder to work correctly
.register_type::<MatchNode<ZState>>()
.run()
}fn add_nodes(
asset_server : Res<AssetServer>,
mut nodes : ResMut<Assets<AnimationNode>>,
) {
// make some image handles
let mut handles = Vec::new();
for i in 0..10 {
handles.push(asset_server.load(format!("SomeSprite_{}", i));
}
// add a node created in this system
// hardcoded like this
let node = Box::new(IndexNode::new("New Node", &handles));
// this will return a handle to the node
let node_handle = nodes.add_node(node);
// this converts our handle into a NodeId
let node_id = NodeId::from_handle(node_handle);
// this can be used to make common nodes easy to refrence
// or to make it easy to refrece from a node loaded from a file
//with a given name
nodes.set(NodeId::from_name("Node Name"), node);
//with a given id
nodes.set(NodeId::from_u64("Node Name"), node);
// load a node from a file
// this will return a handle to a Refrence Node, this is so the node can have a Handle<AnimationNode> diffrent from its FilePath
let from_file = asset_server.load("example.node");
// load a node_tree from a file
// this will return a handle to a Refrence Node, this is also the nodes can have diffrent Handle<AnimationNode> diffrent from its FilePath and so they dont unload if the nodes that my point into the tree where to unload
node_tree.load("example.nodetree");
// Refrence Nodes will run the first Node in there list if you call them so it it ok the use them as start nodes, as long as you are using .node or the first node in the file is correct
}the start node it used to pick the entry point each frame
fn add_animator(
mut commands: Commands,
) {
// create a default state
let mut state = AnimationState::default();
// set starting Attributes
start.set_attribute(Attribute::FlipX, true);
// Attributes data can be any time that derives Reflect
// Attributes can be made from any time that impls `Into<Cow<'static, str>>`
// Attributes made this way will dispay this name when they are debugged
start.set_attribute(Attribute::new_attribute("custom_attribute"), "cat");
// there is a more relaxed way to get Attributes that only requies it impl Hash
// Attributes made this way will **Not** dispay a name when they are debugged
// Atttibute both methodes of getting an attribute are Eq, if T.into::<Cow>().hash() and T.hash()
// are also Eq
start.set_attribute(Attribute::new_attribute_id("specil_attribute"), 5);
// set temporary attribute
// these will be removed if they are not changed each frame
// you can also get index attributes, they follow the same rules but can only be used to get and set usize into the AnimationState
state.set_temporary(Attribute::new_index("Idel"));
// remove temporary attribute
// by default all attributes are persistent
// Index Attributes do not conflict with Custom Attributes
// Attribute::new_index("Idel") != Attribute::new_attribute("Idel")
state.set_persistent(Attribute::new_index_id("Idel"));
// spwan the entity
commands.spwan((
// we need this to see it
SpriteBundle::default(),
// the state the nodes can use so multiple entitys can use the same nodes and get diffrent results
state,
// the first node the entity should run to work out its final sprite
// this can be from a u64, anything that impls Cow<'_, str>, or a Handel<AnimationNode>
StartNode::from_u64(0),
))
}fn update_animation_state(
mut animatiors : Query<&mut AnimationState>,
input : Res<Input<KeyCode>>,
) {
if input.just_pressed(KeyCode::Space){
for mut animatior in animatiors.iter(){
start.set_attribute(Attributes::new_attribute("custom_attribute"), "dog");
}}
}fn read_animation_state(
animatiors : Query<(Entity, &AnimationState)>,
) {
for (entity, animatior) in animatiors.iter(){
if let Ok(ground_type) = animatior.get_attribute::<GroundType>(Attributes::new_attribute("step")) {
println!("{} is on a frame where you should play the sound of someone stepping on {}", entity, ground_type);
}
}
}fn read_animation_change(
animatiors : Query<(Entity, &AnimationState)>,
dogs: Query<&mut Dogs>,
) {
for (entity, animatior) in animatiors.iter(){
// assuming barke is temporary it will only change when set to true.
// use `changed` for logic where you dont care what the attribute
if animatior.changed(Attributes::new_attribute("barke")) {
println!("{} is on a frame where you should play a barke sound effect", entity);
}
}
for (entity, animatior) in animatiors.iter(){
if animatior.changed(Attributes::new_attribute("dog_breed")) {
let dog = dogs.get(animatior.get_attribute::<Entity>(Attributes::new_attribute("dog_breed")));
// do something to the state based on the dog's breed
println!("{} is on a frame where you should play a barke sound effect", entity);
}
}
}