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How to play a tween animation on key press multiple times

I am trying to make a robot that can perform certain animations when keys are pressed.
When I press the "J" key I would like the robot to jump up and down.
I am using Three.js and Tween.js to accomplish this. So far I have a scene made with light and a camera. I am creating the different parts of the robot through functions. I have an example of one of these functions below.
function createHead() {
const head = new THREE.Mesh( new THREE.BoxGeometry(30, 30, 30),
new THREE.MeshLambertMaterial({ color: 0x669999 }));
head.position.y = 30;
head.position.z = -250;
head.rotation.y = 5;
scene.add(head);
var jumpTween = new TWEEN.Tween(head.position).to({y: head.position.y+20}, 1000).repeat(1).yoyo(true).start();
}
Here is my function for updating
function update (event) {
if (String.fromCharCode(event.keyCode) == "J" || isJumping)
{
isJumping = true;
TWEEN.update();
}
// Draw!
renderer.render(scene, camera);
// Schedule the next frame.
requestAnimationFrame(update);
}
When I press "J" my robot jumps once and only once. I cannot press "J" again to get the robot to perform another jump. I was hoping there would be away to just simply "call" a tween on command and have it play on command. However, it seems like TWEEN.update() is the only function that actually runs the tween and in this case, it only runs once. I have been reading the documentation for Tween.js but I am not finding anything helpful.
Edit: I have also tried adding this to my tween.
.onComplete(() => {isJumping = false})
so that it would set isJumping back to false when the animation completes but this did not work.
Thanks for the help.

Three.JS instance can't be re-created

I'm trying to destroy (or destruct or dispose) an 'instance' of Three.JS using this:
Full example: https://jsfiddle.net/v7oLzs4m/58/
function kill() {
const rendererDomWas = renderer.domElement;
renderer.dispose();
controls.dispose();
renderer = scene = camera = controls = null;
document.body.removeChild( rendererDomWas );
shouldRender = false;
}
function animate() {
if(!shouldRender) {return} // no more requesting animation frames if 'shouldRender' is false
frameID = window.requestAnimationFrame( animate );
renderer.render( scene, camera );
}
(i.e. disposing, setting references to null, and stopping the draw loop from touching renderer while shouldRender is false)
It appears to work at first (The renderer content stops showing) but when I re-create the instance, it never comes back.
It's as if something is still... holding onto the GLContext which prevents it from being invoked again.
Why can't I re-create a new instance of Three.JS?

I'm not sure why this works (since I was already doing this in my Fiddle...)
But it turns out the secret ingredient (for me) to letting Three.JS get GC'd/disposed is this:
window.cancelAnimationFrame(frameID);
I suppose that this stops the render function from being stored in the hardware-level draw loop, which holds references to GLContext (and the chain)
The GC can't ever happen unless the 'loop is broken'
(Correct me if I'm wrong please)

How can I loop a GLTF animation in three.js with random intervals?

I am experimenting with creating games using Three.js and I would like to ask if there is a way to animate a GLFT model but instead of having the animation loop I would like to use random intervals. In my case, the game is about taking care of frogs (but I'm cool so I spelled it phrogs) and as an idle animation I want the frogs to croak randomly. Further on in development I also want to add randomly playing animations for movement, eating etc but right now I only need the croaking animation.
Here is the code that loads the model and animates it:
const basePhrog = new GLTFLoader()
var obj
basePhrog.load('assets/models/Phrogs/base phrog/phrog.gltf', function (gltf) {
mixer = new THREE.AnimationMixer(gltf.scene)
obj = gltf.scene
var action = mixer.clipAction(gltf.animations[0])
scene.add(gltf.scene)
action.play()
})
My animate loop looks like this:
function animate () {
requestAnimationFrame(animate)
var delta = clock.getDelta()
if (mixer) mixer.update(delta)
renderer.render(scene, camera)
}
animate()
I hope you can help and thank you for any suggestions!

The glTF file provides an animation (or THREE.AnimationClip in three.js terminology), and the playback of that clip is managed by a THREE.AnimationAction instance. The code in your example will begin playing that animation immediately, and loop it forever, but the AnimationAction does not have to be used that way.
Instead, you could wait and play the action at random intervals:
var action = mixer.clipAction( animation );
action.loop = THREE.LoopOnce;
// Play animation randomly every 1-10s.
setInterval(() => {
action
.reset()
.play();
}, Math.random() * 9000 + 1000);
You can continue to update the AnimationMixer as you are doing now, regardless of whether the animation is playing at any given time.
If you're later trying to play multiple animations on the same object, some of the APIs for transitioning between two animations may be helpful, see the animation / skinning / morph example.

Queue getting multiple video frames

I'm creating a PDF output tool using jsPDF but need to add multiple pages, each holding a canvas image of a video frame.
I am stuck on the logic as to the best way to achieve this as I can't reconcile how to queue the operations and wait on events to achieve the best result.
To start I have a video loaded into a video tag and can get or set its seek point simply with:
video.currentTime
I also have an array of video seconds like the following:
var vidSecs = [1,9,13,25,63];
What I need to do is loop through this array, seek in the video to the seconds defined in the array, create a canvas at these seconds and then add each canvas to a PDF page.
I have a create canvas from video frame function as follows:
function capture_frame(video_ctrl, width, height){
if(width == null){
width = video_ctrl.videoWidth;
}
if(height == null){
height = video_ctrl.videoHeight;
}
canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
var ctx = canvas.getContext('2d');
ctx.drawImage(video_ctrl, 0, 0, width, height);
return canvas;
}
This function works fine in conjunction with the following to add an image to the PDF:
function addPdfImage(pdfObj, videoObj){
pdfObj.addPage();
pdfObj.text("Image at time point X:", 10, 20);
var vidImage = capture_frame(videoObj, null, null);
var dataURLWidth = 0;
var dataURLHeight = 0;
if(videoObj.videoWidth > pdfObj.internal.pageSize.width){
dataURLWidth = pdfObj.internal.pageSize.width;
dataURLHeight = (pdfObj.internal.pageSize.width/videoObj.videoWidth) * videoObj.videoHeight;
}else{
dataURLWidth = videoObj.videoWidth;
dataURLHeight = videoObj.videoHeight;
}
pdfObj.addImage(vidImage.toDataURL('image/jpg'), 'JPEG', 10, 50, dataURLWidth, dataURLHeight);
}
My logic confusion is how best to call these bits of code while looping through the vidSecs array as the problem is that setting the video.currentTime needs the loop to wait for the video.onseeked event to fire before code to capture the frame and add it to the PDF can be run.
I've tried the following but only get the last image as the loop has completed before the onseeked event fires and calls the frame capture code.
for(var i = 0; i < vidSecs.length; i++){
video.currentTime = vidSecs[i];
video.onseeked = function() {
addPdfImage(jsPDF_Variable, video);
};
}
Any thoughts much appreciated.

This is not a real answer but a comment, since I develop alike application and got no solution.
I am trying to extract viddeo frames from webcam live video stream and save as canvas/context, updated every 1 - 5 sec.
How to loop HTML5 webcam video + snap photo with delay and photo refresh?
I have created 2 canvases to be populated by setTimeout (5000) event and on test run I don't get 5 sec delay between canvas/contextes, sometimes, 2 5 sec. delayed contextes get populated with image at the same time.
So I am trying to implement
Draw HTML5 Video onto Canvas - Google Chrome Crash, Aw Snap
var toggle = true;
function loop() {
toggle = !toggle;
if (toggle) {
if (!v.paused) requestAnimationFrame(loop);
return;
}
/// draw video frame every 1/30 frame
ctx.drawImage(v, 0, 0);
/// loop if video is playing
if (!v.paused) requestAnimationFrame(loop);
}
to replace setInterval/setTimeout to get video and video frames properly synced
"
Use requestAnimationFrame (rAF) instead. The 20ms makes no sense. Most video runs at 30 FPS in the US (NTSC system) and at 25 FPS in Europe (PAL system). That would be 33.3ms and 40ms respectively.
"
I am afraid HTML5 provided no quality support for synced real time live video processing via canvas/ context, since HTML5 offers no proper timing since was intended to be event/s controlled and not run as real time run app code ( C, C++ ...).
My 100+ queries via search engine resulted in not a single HTML5 app I intend to develop.
What worked for me was Snap Photo from webcam video input, Click button event controlled.
If I am wrong, please correct me.

Two approaches:
create a new video element for every seek event, code provided by Chris West
reuse the video element via async/await, code provided by Adrian Wong

html 5 canvas: using draw image in game makes loop very slow

i am making a game based on draw images and clear it every some part of second.
i started with:
var peng = new Image();
and then:
peng.onload = function() {
context.drawImage(peng, pengXPosition, pengYPosition, pengWidth, pengHight);
};
and in the loop:
var i=0;
function pengMoveRight(){ i++;if(i==1){peng.src = 'images/1.png';}else if(i==2)
{peng.src = 'images/2.png';} else if(i==3){peng.src = 'images/3.png';}else if(i==4){
peng.src = 'images/4.png';}else if(i==5){peng.src = 'images/5.png';}else if(i==6){
peng.src = 'images/6.png';i-=6;}}
when i run it it works well on IE but on chrome and mozilla it`s too slow and the character is about to disappear .. i used setinterval(); once and window.requestAnimationFrame(); once and both of them cause the same problem.
what should i do to make it smooth move?
here is the full script http://mark-tec.com/custom%20game/

Instead of changing the source, try to create several Image objects instead. That way, the drawImage call can always use a pre-loaded image.

You need to preload all the images or use the sprite method (all images packed into a single sprite) in order to avoid the initial delay caused by the image loading only when it's needed.
However, after that initial problem, your example should run fine once all the images are cached.