Im supernew to javascript animations. I just found out how to add the 2nd movement to my animation.
When running funk() function, the ball goes down to the right. When it triggers funktre() function, the ball goes to its starting marginTop position but keeps its marginLeft position.
Why does it return to the top? I want the 2nd animation, funktre(), to move the ball from the funk() ending position.
const ball = document.querySelector("#en");
ball.addEventListener("click", funk);
function funk() {
let id = null;
let position = 0;
clearInterval(id);
id = setInterval(funkto, 5);
function funkto() {
if (position == 450) {
clearInterval(id);
funktre();
// sett en ny funksjon her
}
else {
stop();
position++;
ball.style.marginLeft = position + "px";
ball.style.marginTop = position + "px";
}
}
};
function stop() {
ball.removeEventListener("click", funk);
};
function funktre() {
let idd = null;
let pos = 0;
clearInterval(idd);
idd = setInterval(funkfire, 5);
function funkfire() {
if (pos == 200) {
clearInterval(idd);
// ny funksjon her
}
else {
pos++;
ball.style.marginTop = pos + "px";
}
}
}
"I want the 2nd animation, funktre, to move the ball from the funk() ending position."
Then you should not initialize its starting position at zero, but at its current position.
function funktre() {
let idd = null;
let pos = parseInt(ball.style.marginTop); // set the initial pos to current pos
clearInterval(idd);
idd = setInterval(funkfire, 5);
function funkfire() {
if (pos == 200) {
clearInterval(idd);
// ny funksjon her
}
else {
pos++;
ball.style.marginTop = pos + "px";
}
}
}
If you intend to program more animations, or even a video game, I would suggest storing the ball top/left position in a global variable (which you could access from any scope).
Related
I'm trying to control video playback depending on where my mouse is on screen.
I've split the width of the window into 3 areas - left, centre and right. This works fine so far.
When the mouse is in the 'left' I want to specify to jump to a certain time, same for centre and right.
The issue I'm having is that every time the mouse moves the video playback restarts, I want it to change only when it changes from 'left' to 'right' or 'centre'. I've made a current_pos and new_pos variable but can't figure out how to update them properly.
Many thanks!
PS have left out the video code for now, just trying to get the position working.
var viewport_width = document.documentElement.clientWidth;
var viewport_height = document.documentElement.clientHeight;
var current_pos;
var new_pos;
function getMousePos(e) {
return {x:e.clientX,y:e.clientY};
}
document.onmousemove=function(e) {
var mousecoords = getMousePos(e);
//left
if (mousecoords.x < viewport_width/3){
current_pos = 'left';
//centre
}else if (mousecoords.x > viewport_width/3 && mousecoords.x < viewport_width*.66){
current_pos = 'centre';
//right
}else {
current_pos = 'right';
}
console.log(current_pos);
};
You need to check whether current_pos has been changed every time you attempt to change it.
var viewport_width = document.documentElement.clientWidth;
var viewport_height = document.documentElement.clientHeight;
var current_pos;
function getMousePos(e) {
return {
x: e.clientX,
y: e.clientY
};
}
document.onmousemove = function(e) {
var mousecoords = getMousePos(e);
//left
if (mousecoords.x < viewport_width / 3) {
if(current_pos != 'left') {
current_pos = 'left';
// Play your video from the desired point
}
//centre
} else if (mousecoords.x > viewport_width / 3 && mousecoords.x < viewport_width * .66) {
if(current_pos != 'centre') {
current_pos = 'centre';
// Play your video from the desired point
}
//right
} else {
if(current_pos != 'right') {
current_pos = 'right';
// Play your video from the desired point
}
}
console.log(current_pos);
};
Need to apply the animateScript() function to different images/divs on mouseover. i think i just need to change my document.querySelector but im not sure how to do so so that it applies to one of the 4 different images.
let tID; //we will use this variable to clear the setInterval()
//let x = event.clientX, y = event.clientY, elementMouseIsOver = document.elementFromPoint(x, y);
function stopAnimate() {
clearInterval(tID);
} //end of stopAnimate()
function animateScript() {
let position = 80; //start position for the image slicer
let height = 0;
const interval = 190; //180 ms of interval for the setInterval()
const diff = 80; //diff as a variable for position offset
const next_row = 110;
let elements = document.querySelectorAll(':hover');
tID = setInterval(() => {
document.querySelector(".avatar").style.backgroundPosition = `-${position}px -${height}px`;
//we use the ES6 template literal to insert the variable "position"
if (height < 220)
{
if (position < 720) {
position = position + diff;
console.log(position);
}
else if (position == 720){
//console.log("height");
position = 80;
height = next_row + height;
console.log("height: ", height);
}
}
else {
if (position < 400) {
position = position + diff;
console.log(position);
}
else if (position == 480){
position = 80;
height = 0;
console.log("height: ", height);
}
}
//reset the position to 256px, once position exceeds 1536px
}, interval); //end of setInterval
} //end of animateScript()
You're hard-coding the .avatar selector, which will always get the first element with that class, so you're correct that that will need to change.
One easy solution would be to pass the hovered element into your function.
const handleMouseEnter = (e) => {
const el = e.target;
animateScript(el);
}
element.addEventListner("mouseenter", handleMouseEnter);
function animateScript(element) {
[...]
tID = setInterval(() => {
element.style.backgroundPosition = `whatever style`;
[...]
}, interval);
}
I know similar questions have been asked before, but the answers did not help me because they are too advanced for me and my simple animation. I am at the very beginning of javascript. On my website, I have the simple code for moving an element from one posotion to another. I would like to have it disappear when it reaches the final position, not fading out, just suddenly disappear. Should I do it with opacity change? How do I write it? My code is the following.
function myMove() {
var elem = document.getElementById("animation");
var pos = 100 ;
var id = setInterval(frame, 5);
function frame() {
if (pos == 380) {
clearInterval(id);
} else {
pos++;
elem.style.top = pos + 'px';
elem.style.left = pos + 'px';
}
}
}
To hide an element simply set style.display to 'none'.
For example:
function myMove() {
var elem = document.getElementById("animation");
var pos = 100 ;
var id = setInterval(frame, 5);
function frame() {
if (pos == 380) {
clearInterval(id);
// this is the key line
elem.style.display = 'none';
} else {
pos++;
elem.style.top = pos + 'px';
elem.style.left = pos + 'px';
}
}
Just as a heads up, using chained setTimeouts can be better than using setInterval in HTML animation. The reason being that if the animation (and/or other scripts on the page) takes longer than the interval the browser will become unresponsive. With a chain of setTimeouts, the clock doesn't start ticking until the end of the current frame.
For example, you could do:
function myMove() {
var elem = document.getElementById("animation");
var pos = 100 ;
function frame() {
if (pos == 380) {
// this is the key line
elem.style.display = 'none';
} else {
pos++;
elem.style.top = pos + 'px';
elem.style.left = pos + 'px';
// set a timeout for 5 ms
setTimeout(myMove, 5);
}
}
I am trying to get this function to be repeatable without resetting.
For example, when i press a button with this function, the button will move to the right from 0px to 100px. When I press the button again it will go from 100px to 200px and so on. It is supposed to animate as well, so it moves 1px at a time until the loop ends.
The code below only works as a one time use, as in it will move from 0px to 100px and pressing it again makes it go 0px to 100px.
I've been working on this for several hours and looked through many sources of help before asking.
function goRight() {
var pos = 0;
var count = pos;
var elem = document.getElementById("main");
var id = setInterval(move, 5);
function move() {
if(pos == count + 100){elem.style.left = pos + 'px'; clearInterval(id);}
else {pos++; elem.style.left = pos + 'px';}
}
}
function goRight() {
var elem = document.getElementById("main"); // the element
var origin = parseInt(elem.style.left) || 0; // get the left of the element (as an origin for the animation), 0 if not set yet
var pos = 0; // pos initialized to 0
var id = setInterval(move, 5);
function move() {
if(pos == 101) { clearInterval(id); } // if pos is 101, then stop the animation
else { pos++; elem.style.left = (origin + pos) + 'px';} // if not, then increment it and set the left of the element to pos + origin
}
}
I think you must only make pos as a global variable and initiate it outside goRight function
like this:
var pos = 0;
function goRight() {
var count = pos;
var elem = document.getElementById("main");
var id = setInterval(move, 5);
function move() {
if(pos == count + 100){elem.style.left = pos + 'px'; clearInterval(id);}
else {pos++; elem.style.left = pos + 'px';}
}
}
Whats wrong in your code is only every time you call goRight pos will be set to zero and again it will begin from start.
but with a global variable it will be save for next time interval will run.
Everything was going smoothly until now. I want to have this hor() function reverse after 20 seconds. The original hor() function grabs an image offscreen and moves it horizontally from the left to the center of the page. I'd like to create a function that does the opposite after 20 seconds. The "after 20 seconds" part is giving me the most grief. If you could show me what a new function would look like or an 'else' addition to the current function that would be great. Thanks.
<script language="JavaScript" type="text/JavaScript">
var x = -500;
var y = 100;
function hor(val) {
if (x <= 500){
x = x + val;
document.getElementById("pos").style.left = x + "px";
setTimeout("hor(5)", 10);
}
}
</script>
<style type="text/css">
<!--
#pos {
position: absolute;
left: -500px;
top: 100px;
z-index: 0;
}
</style>
<body onLoad="setTimeout('hor(5)',5000)">
<div id="pos">
<img src="image.jpg">
</div>
Perhaps you could try changing the script to this:
// Define variables
var x = -500,
y = 100,
direction = 1;
// Function which moves "pos" element
function hor(val) {
// Move by specified value multiplied by direction
x += val * direction;
if(x > 500){
x = 500;
// Reverse direction
direction = -1;
} else if(x < -500){
x = -500;
// Reverse direction, once again
direction = 1;
}
// Move element
document.getElementById("pos").style.left = x + "px";
// Continue loop
setTimeout("hor("+val+")", 10);
}
This code will continue moving the pos element by the specified value until x greater than 500, at which point it will switch direction, then continue until x reaches -500, and so on.
EDIT:
This code will fix that issue with 20 seconds (I had thought that the 500 pixel thing computed to 20 seconds, lol).
// Define variables
var x = -500,
y = 100,
direction = 1;
firstCall = true;
timeElapsed = 0;
// Function which moves "pos" element
function hor(val) {
// Don't let the first call count!
if(!firstCall)timeElapsed += 10;
else firstCall = false;
if(timeElapsed >= 2000){
// Reverse direction
direction *= -1;
timeElapsed = 0;
}
// Move by specified value multiplied by direction
x += val * direction;
// Move element
document.getElementById("pos").style.left = x + "px";
// Continue loop
setTimeout("hor("+val+")", 10);
}
Try this. Here the img is moved horizontally and after sometime it is reverted back to its original position.
<script>
var x = -500;
var y = 100;
var op;
function hor(val) {
if (x <= 500 && x>=-500) {
x = x + val;
document.getElementById("pos").style.left = x + "px";
setTimeout(function(){hor(val);},10);
}
}
$(document).ready(function(){
setTimeout(function(){hor(5);},1000);
setInterval(function(){
setTimeout(function(){hor(-5);},1000);
},2000);
});
</script>
I have changed the timings for testing purpose only, you can change it back.