import { Game } from "../Game" ; import { SceneNode } from "./SceneNode" ; import { linear , Easing } from "../easings" ; /**
 * Function signature for a scene node animator. Function is called with the scene node to animate as first parameter,
 * the current animation time index (0.0 - 1.0) and the elapsed time in seconds as third parameter.
 */ export type SceneNodeAnimator < T extends Game = Game > = ( sceneNode : SceneNode < T > , value : number , elapsed : number ) => void ; /**
 * Constructor arguments for [[SceneNodeAnimation]]
 */ export interface AnimationArgs < T extends Game = Game > { /** The animator function. */ animator : SceneNodeAnimator < T > ; /** Number of seconds to wait until animations starts. Defaults to 0. */ delay ? : number ; /** Duration of the animation in seconds. Defaults to 1. */ duration ? : number ; /** The easing function to use. Defaults to linear. */ easing ? : Easing ; } param T export class SceneNodeAnimation < T extends Game = Game > { /** The scene node to animate. */ private readonly sceneNode : SceneNode < T > ; /** The animator function. */ private readonly animator : SceneNodeAnimator < T > ; /** The delay in seconds before actual animation starts. */ private readonly delay : number ; /** The duration of the animation in seconds. */ private readonly duration : number ; /** The total lifetime of the animation (delay + duration). */ private readonly lifetime : number ; /** The easing function to use for easing the animation. */ private readonly easing : Easing ; /** Time elapsed so far within the animation (including delay). */ private elapsed : number = 0 ; /**
     * Creates scene node animation for the given scene node and with the given animation arguments. You usually
     * don't create an instance of this class yourself. Instead you have to use the [[SceneNode.animate]] method.
     */ public constructor ( sceneNode , { animator , delay = 0 , duration = 1 , easing = linear } ) { this . sceneNode = sceneNode ; this . animator = animator ; this . delay = delay ; this . duration = duration ; this . easing = easing ; this . lifetime = delay + duration ; } param dt public update ( dt ) { this . elapsed += dt ; if ( this . elapsed < this . lifetime ) { if ( this . elapsed > this . delay ) { const timeIndex = ( ( this . elapsed - this . delay ) / this . duration ) % 1 ; this . animator ( this . sceneNode , this . easing ( timeIndex ) , this . elapsed ) ; } return false ; } else { this . animator ( this . sceneNode , 1 , this . lifetime ) ; return true ; } } /**
     * Finishes the animation by fast-forwarding the animation index to the end of the animation lifetime.
     */ public finish ( ) { this . elapsed = this . lifetime ; } }