I am looking to create a scrolling effect similar to that shown here: http://www.seaham-hall.co.uk/
However I am unable to achieve the desired effect, and inspecting the sites code gives me no hints. Quite difficult to google for as it is also quite difficult to describe. The closest I can get to finding a solution is this JSFiddle:
http://jsfiddle.net/xtyus/1/
(function($){
/* Store the original positions */
var d1 = $('.one');
var d1orgtop = d1.position().top;
var d2 = $('.two');
var d2orgtop = d2.position().top;
var d3 = $('.three');
var d3orgtop = d3.position().top;
var d4 = $('.four');
var d4orgtop = d4.position().top;
/* respond to the scroll event */
$(window).scroll(function(){
/* get the current scroll position */
var st = $(window).scrollTop();
/* change classes based on section positions */
if (st >= d1orgtop) {
d1.addClass('latched');
} else {
d1.removeClass('latched');
}
if (st >= d2orgtop) {
d2.addClass('latched');
} else {
d2.removeClass('latched');
}
if (st >= d3orgtop) {
d3.addClass('latched');
} else {
d3.removeClass('latched');
}
if (st >= d4orgtop) {
d4.addClass('latched');
} else {
d4.removeClass('latched');
}
});
})(window.jQuery);
However I am not sure that is going in the right direction, this pulls images up and covers the previous image, but notice on the Seaham Hall site the images don't appear to move up at all, they are stationary and become revealed as you scroll.
How do I recreate this effect? My initial thought was to have the first image shrink as you scroll from 1000px down to 0px, and the second image grow to 1000px, and as you continue to scroll this image then shrinks and the third grows, and so on. However this means that after the first image all the other images have a starting size of 0px and there would technically be no scrolling on the page to begin with, so that is an issue.
My second thought is that perhaps the second image is fixed to the page, the first image slides up revealing the second as you scroll, the second image would not appear to move. Once the first image has gone off the top of the page the second image is detached from the page and allowed to move up with scrolling, while the third image is attached and revealed as the second moves up, this would give the exact effect seen in the Seaham website but I have no clue of it is the correct answer.
If anyone can point me to tutorials or a JSFiddle with a basic concept I can probably figure it out from there. Just stumped what direction to approach this from.
That's a nice effect. Here's one way to do it.
Put each image in a fixed position div, which takes up the entire viewport (initially) and has overflow:hidden.
Set each div's z-index to be higher than the next div's.
As the window scrolls, adjust the height of the divs as a function of the window height times the div's position (index) in the DOM, minus the window's scrollTop:
$(window).scroll(function() {
$('.D').each(function(index) {
$(this).css({
height: $(window).height()*(index+1) - $(window).scrollTop()
});
});
});
Additional content will need a higher z-index than the image divs. And note that z-index works with positioned elements only.
Fiddle
Your desired effect isn't technically a parallax background, but it's close enough that parallax jQuery frameworks should work for you.
I would suggest you research jQuery Parallax plugins as they'll likely provide the functionality you'd like without much custom work. Of course since you're dealing with large images it's also best to keep an eye on the resource management; a good plugin should be fairly efficient but others may be slow or resource intensive.
Check this jquery plugin:ScrollMagic
usage: taken from github
The basic ScrollMagic design pattern is one controller, which has several scenes attached.
Each scene has a definite start and end position and defines what happens when the container is scrolled to the specific offset.
/*
Basic workflow example
*/
// init controller
var controller = new ScrollMagic();
// assign handler "scene" and add it to controller
var scene = new ScrollScene({duration: 100})
.setPin("#my-sticky-element") // pins the element for a scroll distance of 100px
.addTo(controller); // add scene to controller
// adding multiple scenes at once
var scene2 = new ScrollScene();
var scene3;
controller.addScene([
scene2,
scene3 = new ScrollScene({duration: 200}), // add scene and assign handler "scene2"
new ScrollScene({offset: 20}) // add anonymous scene
]);
Related
I need to know if the end of a div element is currently visible in the users' browser.
I tried something I saw on the web, but scrollTop() always gave me zero in my Browser. I read something about an issue in Chrome, but I didn't understand quite well.
jQuery(
function($) {
$('#flux').bind('scroll', function() {
if ($(this).scrollTop() + $(this).innerHeight() >= $(this)[0].scrollHeight) {
alert('end reached');
}
})
}
);
My idea is the following:
1- User loads page and sees a Bar (sticky div at bottom visible page) with some information.
2- After scrolling a bit, and reaching the end of a div element, this bar will position there, after the div. This is the bar's original position
I wasn't really able to know when I was at the end of the div element. Eventually I found this code:
if ($(window).scrollTop() >= $('#block-homepagegrid').offset().top + $('#block-homepagegrid').outerHeight() - window.innerHeight) {
$('.hero-special-message').removeClass('hero-special-messege-scrolling');
} else {
$('.hero-special-message').addClass('hero-special-messege-scrolling');
}
});
I see that it's working, but I'm having a bit of trouble understanding what it does.
I know the following:
1. $(window).scrollTop();
this gives me the amount of pixels the user has scrolled, pretty self explanatory.
2. $('#block-homepagegrid').offset().top;
I THINK this is the distance between the start of the page and the start of the div. I know it's the current coordinates, but what is top exactly here?
3. $('#block-homepagegrid').outerHeight();
this gives the height of the element, I know there are 3, like
height(), innerHeight() and outerHeight(), if you want to take into
account border, margin, padding, which is the better to use?
4. window.innerHeight;
I understand this is what the user sees, but I'm having troubles understanding why does it matter for my situation.
Thanks!
You may be interested in the native JavaScript IntersectionObserver API. It automatically figures out what percentage of a given element is visible in the window and triggers callbacks based on that. So then you can do this:
function visibleHandler(entries) {
if (entries[0].intersectionRatio >= 1.0) {
// The whole element is visible!
} else {
// Part of it is scrolled offscreen!
}
}
const observer = new IntersectionObserver(visibleHandler, {threshold: 1.0});
observer.observe(document.getElementById('flux'));
Now, whenever the element with ID flux is 100% in view, it will trigger the visibleHandler. It will also trigger again if it's scrolled back out of view; that's why the function checks the ratio of visibility to see if it just hit 100% or just got reduced from 100%. You could be more fancy and use the observer entry's insersectionRect, which gives you the rectangle containing the visible portion of the element, and use that to determine top/bottom visibility.
An example, http://www.laravel.com
I want to mimic this effect. I've seen it used a lot across the web lately, but I've never seen a tutorial covering how to create it.
Anyone happen to have some instructions or perhaps a tutorial on recreating this effect?
It's called parallax scrolling. You can do such things with skrollr.js.
And a great tutorial
There are plenty of examples and tutorials for sticky headers,
First link on google search for sticky header http://codepen.io/senff/pen/ayGvD
// Create a clone of the menu, right next to original.
$('.menu').addClass('original').clone().insertAfter('.menu').addClass('cloned').css('position','fixed').css('top','0').css('margin-top','0').css('z-index','500').removeClass('original').hide();
scrollIntervalID = setInterval(stickIt, 10);
function stickIt() {
var orgElementPos = $('.original').offset();
orgElementTop = orgElementPos.top;
if ($(window).scrollTop() >= (orgElementTop)) {
// scrolled past the original position; now only show the cloned, sticky element.
// Cloned element should always have same left position and width as original element.
orgElement = $('.original');
coordsOrgElement = orgElement.offset();
leftOrgElement = coordsOrgElement.left;
widthOrgElement = orgElement.width();
$('.cloned').css('left',leftOrgElement+'px').css('top',0).css('width',widthOrgElement+'px').show();
$('.original').css('visibility','hidden');
} else {
// not scrolled past the menu; only show the original menu.
$('.cloned').hide();
$('.original').css('visibility','visible');
}
}
I have been looking into parallax effects for vertical scrolling on my web page, and after some research, I'm not sure that what I want to do is technically a parallax effect.
From what I've seen, most parallax effects assume you want to be able to scroll indefinitely with many background images rolling by, or with huge images that repeat.
What I want to do is have the background of two DIVs be filled with a background image as the scroll bar reaches the bottom of the page. Note that I do not want the background images to stretch. I'm assuming to get the effect I want that these images would have a vertical height bigger than most people's viewport, and then their vertical position would change. When the user's scrollbar is at the top, a certain amount of the background is visible, and then it moves vertically to fill the background space as the user scrolls down.
Please see the image below for a visual explanation of the effect I hope to acheive:
The height of the veiwport will vary depending on the length of content inside the inner DIV.
My trouble is that if what I am trying to do is not exactly a parallax effect, then I don't know what else to call it, and my attempts to search by describing it keep landing me back at pages offering tutorials on parallax effects. So I've been stumped by a lack of terminology.
If someone could direct me to how I can control the vertical position of the background depending on the scrollbar position, that would be much appreciated. If this can be done with just CSS that would be great, but I'm assuming some Javascript would be required. A jQuery solution would also work for me.
Update:
After searching using the terms provided in comments, I've got the background image in the outer DIV to almost do what I want with the following code:
$(window).scroll(function () {
var yPos = $("#outerDiv").height() - ($("#outerDIV").height() * ($(window).scrollTop() / $(window).height()));
document.getElementById('outerDIV').style.backgroundPosition="0px " + yPos + "px";
});
It moves the background image in the right direction relative to the scrolling, but what it lacks is constraining that motion to within the viewport. Getting the right proportions based on the viewport and DIV sizes is proving to be just a little beyond my mathematical abilities.
For your requirement, you have to use a jquery parallax plugin to guide this activity, my best suggest it to use a Superscollorama and play with the elements as your wish...
As far as your question, Try this example,
controller.addTween(
'#examples-background',
(new TimelineLite())
.append([
TweenMax.fromTo($('#parallax-it-left'), 1,
{css:{backgroundPosition:"(0 -54px)"}, immediateRender:true},
{css:{backgroundPosition:"(0 -54px)"}}),
TweenMax.fromTo($('#parallax-it-right'), 1,
{css:{backgroundPosition:"(0 -54px)"}, immediateRender:true},
{css:{backgroundPosition:"(0 54px)"}})
]),
1000 // scroll duration of tween
);
You serial vice change as far as your wish...
Try practice this plugin, hope that works for you...
http://johnpolacek.github.io/superscrollorama/
Thanks...
Turns out what I want to acheive is possible with no special plugins, just some carefully thought out math. I did use a little jQuery syntax, but I don't think it's strictly necessary.
The code below has copious notes, so hopefully it's largely explanatory. In summary, you just need to find the position of the background image when the scroll would be at the top, and the position it would be if the scroll bar was at the bottom, and then you can use the percentage of the scrollbar's movement to work out where you are between those two points. It's a little tricker than just that, of course, in that you have to account for the difference between the total height of the scroll bar and where your DIV appears on the page and a few other adjustments, but the details of what I did are below.
What I've done here is just for the "outer DIV" that I described in my question. To get a background to move like the "inner DIV" I described, you'd have to modify the code, presumeably by reversing a few parameters. I haven't done that yet, but it seems like a straightforward task.
Hope others find this code useful. If anyone has suggestions on how it can be made more efficient or better, please let me know.
function moveBG(){
// imageHeight is not the total height of the image,
// it's the vertical amount you want to ensure remains visible no matter what.
var imageHeight = 300;
// Get the maximum amount within the DIV that the BG can move vertically.
var maxYPos = $("#outerDIV").height() - imageHeight;
// Get the amount of vertical distance from the top of the document to
// to the top of the DIV.
var headerHeight = document.getElementById("outerDIV").offsetTop;
// Calculate the BG Y position for when the scrollbar is at the very top.
var bgTopPos = $(window).height() - headerHeight - imageHeight;
// I don't want the image to wander outside of the DIV, so ensure it never
// goes below zero.
if (bgTopPos < 0)
{
bgTopPos = 0;
}
// Calculate the BG Y position when the scrollbar is at the very top.
var bgBottomPos = $(document).height() - $(window).height() - headerHeight;
// To prevent the BG image from getting cut off at the top, make sure
// its position never exceeds the maximum distance from the top of the DIV.
if (bgBottomPos > maxYPos)
{
bgBottomPos = maxYPos;
}
// Subtract the top position from the bottom, and you have the spread
// the BG will travel.
var totalYSpan = bgBottomPos - bgTopPos;
// Get the scrollbar position as a "percentage". Note I simply left it as a
// value between 0 and 1 instead of converting to a "true" percentage between
// 0 and 100, 'cause we don't need that in this situation.
var scrollPercent = ($(window).scrollTop() / ( $(document).height() - $(window).height()));
// The percentage of spread is added to the top position, and voila!
// You have your Y position for the BG image.
var bgYPos = bgTopPos + (Math.round(totalYSpan * scrollPercent));
// Apply it to the DIV.
document.getElementById('outerDIV').style.backgroundPosition="0px " + bgYPos + "px";
}
// Place the BG image correctly when opening the page.
$(document).ready(function() {
moveBG();
});
// Make it update when the scrollbar moves.
$(window).scroll(function () {
moveBG();
});
Ok - here is what I am trying to do. I was looking online for a cool timeline that I can purchase - allowing zoom in zoom out, posting of events on it, and so on. However, all the examples I found are either too expensive or just downright useless.
So, I have decided to create my own, but there are two elements that I am having trouble with.
1) Converting the wheel scroll to left-right scrolling (so not up-down). I can't seem to find an easy and quick way to do this.
But, more importantly..
2) I need the area I will be showing the timeline on to automatically expand as I go about my scrolling. So, if I scroll down, it will add an "equivalent" area on the right, and down, on the left. So I was thinking like making an iFrame (already use these) and when you scroll it just adds more "timeline" on the left or the right, loads what ever it needs to load from the DB/list of events, and so on, ad infinitum, thus creating an ever-expanding list of blocks that are time-sized.
If I can do the two things above, then I am set - the rest (loading/positioning) I can figure out - just these two things are eluding my imagination and ability to find an answer.
Basically you need a horizontal infinite scroll script.
Take this plugin I wrote:
$.fn.hScroll = function( options )
{
function scroll( obj, e )
{
var evt = e.originalEvent;
var direction = evt.detail ? evt.detail * (-120) : evt.wheelDelta;
if( direction > 0)
{
direction = $(obj).scrollLeft() - 120;
}
else
{
direction = $(obj).scrollLeft() + 120;
}
$(obj).scrollLeft( direction );
e.preventDefault();
}
$(this).width( $(this).find('div').width() );
$(this).bind('DOMMouseScroll mousewheel', function( e )
{
scroll( this, e );
});
}
Initialize it with:
$('body').hScroll();
Makes your website a horizontally scrollable website.
Your content div must be wider than your body (ex. 3000px).
As for the infinite scrolling effect you pretty much gotta do that your self because I can't know what kind of data you'll input. But I'll explain.
Your children elements in the content div must be floated to left. (every new appended div will not go to new line).
Set an interval to check if the user's scrollLeft position is near the end of the content (just like pinterest and similar site).
function loadNewData(){ /* Your search for data and update here. */ }
setInterval('loadNewData', 500);
search for new data according to your last one with AJAX. When you get new data, append it into your content div (in a div that's floated left, as I wrote previously), and mark it as your last item.
Maybe you could use your ID to mark the last item on it's div.
<div data-id="467" class="item"> // your data here </div>
You can fetch it with
$('.item:last').attr('data-id');
with jQuery.
I have a list of images on a page. As I scroll through the page I would like to show some options in a naviationbar of the image currently in the viewport. Therefore I need to get the image element currently in the viewport, is this possible ?
Jakob
Who says there's just one image in viewport? What would you like to do when there are many?
But otherwise you can always get the scroll position of your container with images as well as your images' top offset to see which one is currently in-view.
So these values will get you to your result
container scroll position
container visible client height
images' top offset
Using these values will make it possible to locate all images in the view regardless whether they're fully or partially displayed (at the top or bottom).
This is a simplified JSFiddle that gives red border around the first fully-in-the-view image. The code does this:
// get top positions and references to all images
var pos = $("img").map(function(){
var $this = $(this);
return {
el: $this,
top: $this.offset().top
};
}).get();
// provide document scrolling
$(document).on("scroll", function() {
$("img").removeClass("first-in-view");
var scroll = $(this).scrollTop();
var i = 0;
while(pos[i].top < scroll) i++;
pos[i].el.addClass("first-in-view");
}).scroll();
This should be optimised to only toggle class when it needs to. Otherwise we have flickering in every scroll. But it demonstrates how this can be done and you can get going from here.
IMPORTANT
It is utterly important that you attach your image position determining process on document load event and not the usually use DOM ready, because you have to wait for the document to load in order for your images to have final positions.