Creating random image flicker - javascript

Basically I'm trying to make a skull flicker over a persons face, I've achieved it flashing up once. But the effect I'm trying to achieve is that it looks more organic and random. Here's the basic structure:
function flicker() {
var maxFlick = 6,
amount = Math.round(Math.random() * maxFlick),
running = false;
function showHide() {
$flicker.show();
running = true;
setTimeout(function() {
$flicker.hide();
running = false;
}, 100)
}
for (i = 0; i < amount; i++) {
if(!running) {
showHide();
}
}
}
setInterval(flicker, 4000);
I had presumed that running a for loop with a random amount statement would produce the desired effect, but it's still only flashing up once every 4000milliseconds as previously. Any pointers?

With the help of Regent and this fiddle I came up with the answer:
function flicker() {
var maxFlick = 6,
amount = Math.round(Math.random() * maxFlick),
delta = 2,
timer;
var doneFlicks = 0;
var flickInterval = setInterval(showHide, timer);
function showHide() {
timer = Math.round((Math.random() + delta) * 100)
$flicker.show();
var hide = setTimeout(function() {
$flicker.hide();
doneFlicks++
}, 20)
if (doneFlicks == amount) {
clearInterval(flickInterval);
}
}
}
setInterval(flicker, 3000);
This produces a randomised flicker effect that's called every 3 seconds - perfect for a horror film effect!
Thanks again to Regent for all the help!

Related

if body has class Fade in mp3 sound else fade out

I am trying to fade the volume of an mp3 in to 1 if the body has the class fp-viewing-0
How ever this isn't working and the volume doesn't change how can I fix this?
Code:
var audio0 = document.getElementById('audio-0');
audio0.volume = 0;
setInterval( function(){
if ($("body").hasClass("fp-viewing-0")) {
audio0.animate({volume: 1}, 1000);
}
else {
audio0.animate({volume: 0}, 1000);
}
}, 100);
HTML
<audio id="audio-0" src="1.mp3" autoplay="autoplay"></audio>
I've also tried:
$("#audio-0").prop("volume", 0);
setInterval( function(){
if ($("body").hasClass("fp-viewing-0")) {
$("#audio-0").animate({volume: 1}, 3000);
}
else {
$("#audio-0").animate({volume: 0}, 3000);
}
}, 100);
Kind Regards!
I have changed the jquery animate part to a fade made by hand. For that i created a fade time and steps count to manipulate the fade effect.
var audio0 = document.getElementById('audio-0');
audio0.volume = 0;
if ($("body").hasClass("fp-viewing-0")) {
audio0.volume = 1; //max volume
var fadeTime = 1500; //in milliseconds
var steps = 150; //increasing makes the fade smoother
var stepTime = fadeTime/steps;
var audioDecrement = audio0.volume/steps;
var timer = setInterval(function(){
audio0.volume -= audioDecrement; //fading out
if (audio0.volume <= 0.03){ //if its already inaudible stop it
audio0.volume = 0;
clearInterval(timer); //clearing the timer so that it doesn't keep getting called
}
}, stepTime);
}
Better would be to place all of this in a function that receives these values a fades accordingly so that it gets organized:
function fadeAudio(audio, fadeTime, steps){
audio.volume = 1; //max
steps = steps || 150; //turning steps into an optional parameter that defaults to 150
var stepTime = fadeTime/steps;
var audioDecrement = audio.volume/steps;
var timer = setInterval(function(){
audio.volume -= audioDecrement;
if (audio.volume <= 0.03){ //if its already inaudible stop it
audio.volume = 0;
clearInterval(timer);
}
}, stepTime);
}
Which would make your code a lot more compact and readable:
var audio0 = document.getElementById('audio-0');
audio0.volume = 0;
if ($("body").hasClass("fp-viewing-0")) {
fadeAudio(audio0, 1500);
}

Continuously fade in and out random pictures

I am trying to get make a function that will continuously fade in and out pictures that are randomly selected, so that the same picture doesn't come up twice. I can get it to fade out / change image / fade in once if it is clicked with
$("img").click(function() { CODE });
but I have to click the image each time, and I am getting stuck trying to make it into a function that is called when the page has loaded:
$(document).ready(function() {
$("img").fadeOut(2000, function() {
while (picPicker1 === picPicker2) {
picPicker2 = (Math.floor(Math.random() * 5) - 1);
}
var source = pics[picPicker2];
$("img").attr("src", source);
$("img").fadeIn(2000);
picPicker1 = picPicker2;
});
});
pics[] is an array with the web addresses of five different pictures. I also tried using setInterval, but that didn't work either. New to all of these languages so thank you in advance for your patience!
setInterval was the correct function to use. The code you've provided in your question is missing a closing });.
Here's some basic code that makes use of setInterval to change the image:
JQuery:
var pics = [
"https://placehold.it/350x150/ff0000",
"https://placehold.it/350x150/00ff00",
"https://placehold.it/350x150/0000ff",
"https://placehold.it/350x150/F2F5A9",
"https://placehold.it/350x150/FF00FF",
];
setInterval(function() {
var picPicker2 = (Math.floor(Math.random() * 5) + 1);
var source = pics[picPicker2];
$("img").fadeOut(500).attr("src", source).fadeIn(500);
}, 2000);
Note: The images will repeat occasionally, but the code I've provided is only a base for you to improve upon.
Fiddle Demo
You can either use setInterval(), for (x = 5; x > 0; x ++) {}, var x = 0; do {} while (x = 0);, or var x = 0; while (x = 0) {}.
$(document).ready(function() {
var picPicker, source;
function generateImage() {
$("img").fadeOut(2000, function() {
picPicker = (Math.floor(Math.random() * 200));
source = 'https://unsplash.it/400/300/?image=' + picPicker;
$("img").attr("src", source);
$("img").fadeIn(2000);
});
setTimeout(generateImage, 5000);
}
generateImage();
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<img src="https://unsplash.it/400/300/?image=1">

Trying to randomize words from an array and stop the loop after 5

I'm trying to write a script that will pick a random word from an array called words, and stop the loop after 5 times and replace the html with Amazing. so it always ends on amazing. Can't figure out best practice for something like this. My thinking is there just don't know where to put the script ender or how to properly implement this.
I feel like I need to implement something like this into my script, but can't figure out where. Please help.
if(myLoop > 15) {
console.log(myLoop);
$("h1").html('AMAZING.');
}
else {
}
Here is the Javascript that I'm using to loop and create bring new words in.
$(document).ready(function(){
words = ['respected​', 'essential', 'tactical', 'effortless', 'credible', 'smart', 'lucid', 'engaging', 'focussed', 'effective', 'clear', 'relevant', 'strategic', 'trusted', 'compelling', 'admired', 'inspiring', 'cogent', 'impactful', 'valued']
var timer = 2000,
fadeSpeed = 500;
var count = words.length;
var position, x, myLoop;
$("h1").html(words[rand(count)]);
function rand(count) {
x = position;
position = Math.floor(Math.random() * count);
if (position != x) {
return position;
} else {
rand(count);
}
}
function newWord() {
//clearTimeout(myLoop); //clear timer
// get new random number
position = rand(count);
// change tagline
$("h1").fadeOut(fadeSpeed, function() {
$("h1").slideDown('slow'); $(this).html(words[position]).fadeIn(fadeSpeed);
});
myLoop = setTimeout(function() {newWord()}, timer);
}
myLoop = setTimeout(function() {newWord()}, timer);
});
Here's my codepen
http://codepen.io/alcoven/pen/bNwewb
Here's a solution, which uses a for loop and a closure.
Words are removed from the array using splice. This prevents repeats.
I'm using jQuery delay in place of setTimeout:
var i, word, rnd, words, fadeSpeed, timer;
words = ['respected​', 'essential', 'tactical', 'effortless', 'credible', 'smart', 'lucid', 'engaging', 'focused', 'effective', 'clear', 'relevant', 'strategic', 'trusted', 'compelling', 'admired', 'inspiring', 'cogent', 'impactful', 'valued'];
fadeSpeed = 500;
timer = 2000;
for(i = 0 ; i < 6 ; i ++) {
if(i===5) {
word= 'awesome';
}
else {
rnd= Math.floor(Math.random() * words.length);
word= words[rnd];
words.splice(rnd, 1);
}
(function(word) {
$('h1').fadeOut(fadeSpeed, function() {
$(this).html(word);
})
.slideDown('slow')
.delay(timer)
.fadeIn(fadeSpeed);
}
)(word);
}
h1 {
text-transform: uppercase;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<h1></h1>
I added an iteration counter to check how many times it has changed.
Added this by other variables:
var iter = 1;
Added this in the newWord function:
iter = iter + 1;
if (iter > 5) {
return;
}
var word;
if (iter == 5) {
word = 'awesome';
}
else {
...
Here's my solution by changing your code:
http://codepen.io/anon/pen/YPGWYd

JQuery Auto Click

I have a problem, I have 3 button lets say it's called #pos1, #pos2 and #pos3.
I want to makes it automatically click #pos1 button in 2 seconds, after that click the #pos2 after another 2 seconds, and #pos3 after another 2 seconds,
after that back to the #pos1 in another 2 seconds and so on via jQuery.
HTML
<button id="pos1">Pos1</button>
<button id="pos2">Pos2</button>
<button id="pos3">Pos3</button>
Anyone can help me please?
Try
$(function() {
var timeout;
var count = $('button[id^=pos]').length;
$('button[id^=pos]').click(function() {
var $this = $(this);
var id = $this.attr('id');
var next = parseInt(id.substring(4), 10) + 1;
if( next >= count ){
next = 1
}
if (timeout) {
clearTimeout(timeout);
}
timeout = setTimeout(function() {
$('#pos' + next).trigger('click');
}, 2000);
})
timeout = setTimeout(function() {
$('#pos1').trigger('click');
}, 2000);
})
var posArray = ["#pos1", "#pos2", "#pos3"];
var counter = 0;
setInterval(function() {
$(posArray[counter]).triggerHandler('click');
counter = ((counter<2) ? counter+1 : 0);
}, 2000);
That should do the trick, though you did not mention when you want it to stop running.
Well I don't know what you already have but technically it could be done via triggerHandler()
var currentPos = 1,
posCount = 3;
autoclick = function() {
$('#pos'+currentPos).triggerHandler('click');
currentPos++;
if(currentPos > posCount) { currentPos = 1; }
};
window.setInterval(autoclick,2000);
If I have understood you question right, you need to perform click in a continuous loop in the order pos1>pos2>pos3>pos1>pos2 and so on. If this is what you want, you can use jQuery window.setTimeout for this. Code will be something like this:
window.setTimeout(performClick, 2000);
var nextClick = 1;
function performClick() {
if(nextClick == 1)
{
$("#pos1").trigger("click");
nextClick = 2;
}
else if(nextClick==2)
{
$("#pos2").trigger("click");
nextClick = 3;
}
else if(nextClick == 3)
{
$("#pos3").trigger("click");
nextClick = 1;
}
window.setTimeout(performClick, 2000);
}
This is quite buggy but will solve your problem.
using setInterval()
Calls a function or executes a code snippet repeatedly, with a fixed time delay between each call to that function.
var tempArray = ["pos1", "pos2", "pos3"]; //create an array to loop through
var arrayCounter = 0;
setInterval(function() {
$('#' + tempArray[arrayCounter ]).trigger('click');
arrayCounter = arrayCounter <2 ? arrayCounter +1 : 0;
}, 2000);
fiddle here
check your console for fiddle example

Javascript/jquery fade effect decay

Pretty specific one this time, I have the following code to loop some fades depending on conditions, as you can see depending on the state the animation differs slightly.
At the moment it is producing the effect I want but it seem's to slow down gradually until at around 3 minutes it stops completely.
I've gotten to the point where I can't stare at it any longer! can anyone offer me some advice on how to make this a continuous loop?
Here's a fiddle: http://jsfiddle.net/CbNc5/
var glimmerLen = 16;
var initiated = false;
var animateLoop = false;
var timeout;
function glimmerAnimate() {
if (!initiated) {
timeout = window.setTimeout(function() {glimmerAnimate();}, 2500);
initiated = true;
} else if (!animateLoop && initiated) {
$("#glimmer li").fadeTo(1500, 0.5, function(){
glimmerAnimate();
animateLoop = true;
});
} else if (animateLoop) {
var rangeMax = glimmerLen + 1;
var randObj = Math.floor(Math.random() * rangeMax);
$("#glimmer-" + randObj).fadeTo(1500, 0.8, function() {
$("#glimmer-" + randObj).fadeTo(2000, 0.2);
glimmerAnimate();
});
}
}
I have rewrite this, hope this help (http://jsfiddle.net/CbNc5/5/)
function fadeLoop(e) {
$(e).fadeTo(Math.random() * 500, 0.2, function () {
$(this).fadeTo(Math.random() * 500, 1, function () {
fadeLoop(this);
});
});
}
$('li').each(function () {
fadeLoop(this);
});
P.S. If you only want loop opacity, you can use CSS3, it will be more simple

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