Animation Events do not Trigger on Speed -1

im currently trying to animate various Objects. The Objects have one Animation attached (in an Anim State Graph) and in this Animation the Objects are changing their visuals. I want to change them stepwise, so i have some Animation Events set. When the Animation is playing at speed 1 the Events are getting fired correct. But when i try to revert the Animation (speed = -1) the Events do not fire.

AnimationHandler.prototype.initialize = function() {
    this.state = 'small'
    this.entity.anim.playing = false;

    this.entity.anim.on('anim-small', ()=>{
        this.state = 'small';
        this.entity.anim.playing = false;

    this.entity.anim.on('anim-normal', ()=>{
        this.state = 'normal';
        this.entity.anim.playing = false;

    this.entity.anim.on('anim-big', ()=>{
        this.state = 'big';
        this.entity.anim.playing = false;


AnimationHandler.prototype.bigger = function(){
    this.entity.anim.speed = 1;
    this.entity.anim.playing = true;

AnimationHandler.prototype.smaller = function(){
    this.entity.anim.speed = -1;
    this.entity.anim.playing = true;

Is there a way to play the Animation backwards WITH the Events fire?

Engine 1.65.0 adds support for this, see Releases · playcanvas/engine · GitHub - change #5413 adds this.

This engine version is in testing at the moment (you can already use it in the Editor by running with Release Candidate build). The official release to the Editor is planned sometimes around the 16th of August.

okay, thank you ^^

The Engine 1.65.3 is released already a few days. Still the Events are not getting fired while the Animation is running backwards (at -1 speed).
Is there something special i have to do in Code?

You need to have your events added in code I believe. When those are added, they should play when playing forward, but with Handle anim events during reverse playback by ellthompson · Pull Request #5413 · playcanvas/engine · GitHub they should also play when the speed is less than zero (negative)