I have read about how using translate has better performance, but it seems they behave slightly differently: using left:100% moves the animated object all the way to the end of the screen, whereas translate(100%) only moves the animated object as far as its length. That is, it moves 100% of the screen versus 100% of the object.
Can explain why this is, and what can be done to reproduce the same behavior when using translate?
You can see a demo here: http://jsfiddle.net/32VJV/1/
.slide_1 {
top: 0px;
left:0%;
position: absolute;
overflow: hidden;
font-size: 30px;
}
.slide_1 {
-webkit-animation: slide 3s infinite;
-webkit-animation-delay: 0s;
-webkit-animation-fill-mode:forwards;
-webkit-transform-origin: 0% 0%;
}
.slide_2 {
top: 25px;
left:0%;
position: absolute;
overflow: hidden;
font-size: 30px;
}
.slide_2 {
-webkit-animation: slide2 3s infinite;
-webkit-animation-delay: 0s;
-webkit-animation-fill-mode:forwards;
-webkit-transform-origin: 0% 0%;
}
#-webkit-keyframes slide {
0% {
-webkit-transform: translate(0%);
}
50% {
-webkit-transform: translate(100%);
}
100% {
-webkit-transform: translate(0%);
}
}
#-webkit-keyframes slide2 {
0% {
left 0%;
}
50% {
left:100%;
}
100% {
left:0%;
}
}
<div style="font-size:18px;">
<div class=""> <span class="slide_1" id="dimensions">ABC</span> <span class="slide_2" id="dimensions">ABC</span>
</div>
</div>
The difference between the two is that animating a property like left will keep the element in the flow of the document whereas translate does not.
For more information on why you might use one or the other, Paul Irish has an excellent write up (with links to more information): Why Moving Elements With Translate() Is Better Than Pos:abs Top/left
There's also a lot of great information on browser performance at jankfree.org
Solution for the translate animation: make the element as wide as the window:
Example
slide_1 {
top: 0px;
left:0%;
right: 0;
position: absolute;
overflow: hidden;
font-size: 30px;
}
An interesting exercise: Open your devtools and what what happens when you activate one animation at a time.
In Chrome:
The translate animation has basically nothing going on except a periodic GC
The Left animation you will see repeatedly:
Recalculate Style
Layout
Pain Setup
Paint
Composite Layers
In this case, the overhead it pretty small, but that can change quickly depending on what is being moved around the screen.
Related
This is my first time asking a question on here and I've found questions that are somewhat similar, but haven't worked for my issue.
I am trying to spin a word across the screen from off-screen left to off-screen right. The center of the word should be it's rotation point (ie word spins in place from left side of screen to right). I have tried using variations of translateX and rotate, but it either rotates in place or moves left to right. When it does move from the left to right off the screen, it keeps extending the bounds of my screen and stretching it before it loops back to the left side. Any ideas how I can solve this? Seems simple, but I'm terrible with animations.
.move {
position: absolute;
animation: moveword 10s infinite linear;
}
.spin {
position: absolute;
animation: spin 7s infinite linear;
}
#keyframes spin {
from {
transform: rotate(0deg);
}
to {
transform: rotate(360deg);
}
}
#keyframes moveword {
from {
left: -10%;
}
to {
left: 95%;
}
}
Based on code that you provide, I assume you could make something like this.
overflow: hidden needs to be applied to separate element, not the <body> because it restricts scrolling.
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
.page {
position: relative;
width: 100vw;
height: 100vh;
overflow: hidden;
}
.word {
position: absolute;
top: 5px;
left: 5px;
animation: word-anim 10s infinite linear;
}
#keyframes word-anim {
0% {
transform: translateX(0px) rotateZ(0deg);
}
70% {
transform: translateX(70vw) rotateZ(360deg);
}
100% {
transform: translateX(100vw) rotateZ(360deg);
}
}
<div class="page">
<span class="word">A word</span>
</div>
I have a div element, which has an animation to play when starting the page. I want to make it have another animation to play when I'm hovering over it. It works just fine, but when I get my mouse out of the div element, it plays the starting animation again (fades in from out of the screen).
#keyframes div{
0%{
opacity: 0;
}
}
#keyframes divHover{
50%{
top: 200px;
}
100%{
top: 0px;
}
}
#div{
opacity: 1;
animation: div 1s;
position: absolute;
left: 0px;
top: 0px;
}
#div:hover{
animation: divHover 1s linear 0s infinite;
}
<div id="div"> abc </div>
Expected:
Div starts invisible and fades in. When hovering div, it goes up and down, and keeps doing it while hovering. After stopping the hover, div stops the animation and keeps its full opacity
Actual:
After stopping the hover, div stops the animation but returns to 0 opacity, then takes one second to display the starting animation again.
https://jsfiddle.net/odq125Lu/6/
The issue is due to the fact that you are overriding the first opacity animation with the up & down one then when you unhover you active the first one again.
You can use multiple animations and consider animation-play-state to activate the second one:
#keyframes div {
0% {
opacity: 0;
}
}
#keyframes divHover {
50% {
top: 200px;
}
100% {
top: 0px;
}
}
#div {
opacity: 1;
animation:
div 1s,
divHover 1s linear 0s infinite;
animation-play-state:running,paused;
position: absolute;
left: 0px;
top: 0px;
background:red;
padding:20px;
}
#div:hover {
animation-play-state:running,running;
}
<div id="div"> abc </div>
I'm no expert, but it may have something to do with the fact that you haven't set a 100% value for the animation "divHover"?
#keyframes div{
0%{
opacity: 0;
}
100% {
opacity: 1;
}
}
I'm trying to animate a background image position smoothly with CSS over a longer period, let's say 60 seconds:
#movingbackground {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
background-image: url('https://upload.wikimedia.org/wikipedia/commons/thumb/6/68/Bigsurflowers.jpg/1280px-Bigsurflowers.jpg');
overflow: hidden;
background-position: left center;
animation: zoomin 60s ease-in infinite;
}
#-webkit-keyframes zoomin {
0% { background-position: 0% center; transform: scale(1.0); }
50% {background-position: 100% center; transform: scale(1.2); }
100% { background-position: 0% center; transform: scale(1.0); }
}
#keyframes zoomin {
0% { background-position: 0% center; transform: scale(1.0); }
50% {background-position: 100% center; transform: scale(1.2); }
100% { background-position: 0% center; transform: scale(1.0); }
}
<div id="movingbackground"></div>
The small movements in the beginning and end are "jumping" a few pixel every second instead of moving slowly (may depend on screen size).
The reason for that is probably that there is not enough movement to fill the required number of frames, especially when the animation is eased. As I think I have seen this effect working smoothly somewhere I wonder how to work around this.
Here's a Fiddle as well.
Animation of background-position makes browser to do layout, paint and composite.
Re-layout and re-paint are heavy on CPU and cause "jumping".
Instead of that, you might apply your background to pseudo-element (or use <img> in your HTML) and animate its transform property using 3d transformation.
It will make browser to use GPU for the animation and animation will run in composition phase pretty smoothly.
See the snippet below:
html,
body {
margin: 0;
padding: 0
}
#movingbackground {
position: relative;
width: 100vw;
height: 100vh;
overflow: hidden;
}
#movingbackground:before {
content: '';
position: absolute;
top: 0; left: 0; z-index: -1;
height: 100%;
width: 200%;
background: url(https://upload.wikimedia.org/wikipedia/commons/thumb/6/68/Bigsurflowers.jpg/1280px-Bigsurflowers.jpg) 0 50% / cover;
animation: zoomin 60s ease-in infinite;
}
#keyframes zoomin {
50% {
transform: translateX(-50%) scale(1.2)
}
}
<div id="movingbackground"></div>
I did some testing and came to the conclusion that it's probably impossible. (At least with transitions or animations)
The problem is the way browsers render images on a screen. The pixels of the image apparently get lined up with those of your screen.
So the picture always "jumps" exactly one pixel at a time.
That means, that the more pixels you have in your image, the more steps it will make. But when using ease-in it will always stutter in the beginning.
As I think I have seen this effect working smoothly somewhere
That was probably not realized with css.
If I have two lines of text one on top of the other. Content of each line is dynamic.
Is there a way to set animation speed in pixels per second? So that line would scroll with same speed regardless of their length?
Example of the situation:
div {
width: 50%;
padding-left: 10%;
float: left;
height: 50px;
overflow: hidden;
position: relative;
}
#line1 {
background-color: green;
}
#line2 {
background-color: yellow;
}
h4 {
position: absolute;
height: 100%;
margin: 0;
line-height: 50px;
text-align: left;
/* Apply animation to this element */
/* Animation delay 0.5s */
-moz-animation: line-scroll 15s linear 0.5s infinite;
-webkit-animation: line-scroll 15s linear 0.5s infinite;
animation: line-scroll 15s linear 0.5s infinite;
}
#line1 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 200%;
}
#line2 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 600%;
}
#keyframes line-scroll {
0% {
-moz-transform: translateX(0%);
/* Firefox bug fix */
-webkit-transform: translateX(0%);
/* Firefox bug fix */
transform: translateX(0%);
}
100% {
-moz-transform: translateX(-100%);
/* Firefox bug fix */
-webkit-transform: translateX(-100%);
/* Firefox bug fix */
transform: translateX(-100%);
}
}
<div id="line1">
<h4>I don't want to come off as arrogant here, but I'm the greatest botanist on this planet.</h4>
</div>
<div id="line2">
<h4>Every human being has a basic instinct: to help each other out. If a hiker gets lost in the mountains, people will coordinate a search. If a train crashes, people will line up to give blood. If an earthquake levels a city, people all over the world will send emergency supplies. This is so fundamentally human that it's found in every culture without exception. Yes, there are assholes who just don't care, but they're massively outnumbered by the people who do. ~ Mark Watney, The Martian</h4>
</div>
Means of AngularJS directive and CSS are welcome.
You can use JQuery (javascript) to get the width of headings and than calculate the duration based on the width i.e duration per pixel
width() method of jquery is used to get width of the headings.
I calculate the the duration as follows:
1s = 20px
Therefore 100px = 100/20
= 5s
You can increase the denominator (see the number10) in var dur1=Math.ceil(w1/10) to speed up the scrolling.
Here is the code
//getting the width of both the headings
var w1=$("#line1>h4").width();
var w2=$("#line2>h4").width();
//calculating the duration of the animation dynamically based on the width
var dur1=Math.ceil(w1/10);
var dur2=Math.ceil(w2/10);
//setting the duration dynamically
$("#line1>h4").css("animation-duration",dur1+"s");
$("#line2>h4").css("animation-duration",dur2+"s");
div {
width: 50%;
padding-left: 10%;
float: left;
height: 50px;
overflow: hidden;
position: relative;
}
#line1 {
background-color: green;
}
#line2 {
background-color: yellow;
}
h4 {
position: absolute;
height: 100%;
margin: 0;
line-height: 50px;
text-align: left;
/* Apply animation to this element */
/* Animation delay 0.5s */
-moz-animation: line-scroll 15s linear 0.5s infinite;
-webkit-animation: line-scroll 15s linear 0.5s infinite;
animation: line-scroll 15s linear 0.5s infinite;
}
#line1 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 200%;
}
#line2 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 600%;
}
#keyframes line-scroll {
0% {
-moz-transform: translateX(0%);
/* Firefox bug fix */
-webkit-transform: translateX(0%);
/* Firefox bug fix */
transform: translateX(0%);
}
100% {
-moz-transform: translateX(-100%);
/* Firefox bug fix */
-webkit-transform: translateX(-100%);
/* Firefox bug fix */
transform: translateX(-100%);
}
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="line1">
<h4>I don't want to come off as arrogant here, but I'm the greatest botanist on this planet.</h4>
</div>
<div id="line2">
<h4>Every human being has a basic instinct: to help each other out. If a hiker gets lost in the mountains, people will coordinate a search. If a train crashes, people will line up to give blood. If an earthquake levels a city, people all over the world will send emergency supplies. This is so fundamentally human that it's found in every culture without exception. Yes, there are assholes who just don't care, but they're massively outnumbered by the people who do. ~ Mark Watney, The Martian</h4>
</div>
In CSS you must provide the animation duration in time units, which is currently seconds / miliseconds.
You could, however, adapt the width of the transition by switching from a %-value to px-values like shown below:
div {
width: 50%;
padding-left: 10%;
float: left;
height: 50px;
overflow: hidden;
position: relative;
}
#line1 {
background-color: green;
}
#line2 {
background-color: yellow;
}
h4 {
position: absolute;
height: 100%;
margin: 0;
line-height: 50px;
text-align: left;
/* Apply animation to this element */
/* Animation delay 0.5s */
-moz-animation: line-scroll 15s linear 0.5s infinite;
-webkit-animation: line-scroll 15s linear 0.5s infinite;
animation: line-scroll 15s linear 0.5s infinite;
}
#line1 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 200%;
}
#line2 h4 {
/* width must be big enought to fit in whole text othrwise
whole text will not scroll into view */
width: 600%;
}
#keyframes line-scroll {
0% {
-moz-transform: translateX(0%);
/* Firefox bug fix */
-webkit-transform: translateX(0%);
/* Firefox bug fix */
transform: translateX(0%);
}
100% {
-moz-transform: translateX(-1000px);
/* Firefox bug fix */
-webkit-transform: translateX(-1000px);
/* Firefox bug fix */
transform: translateX(-1000px);
}
}
<div id="line1">
<h4>I don't want to come off as arrogant here, but I'm the greatest botanist on this planet.</h4>
</div>
<div id="line2">
<h4>Every human being has a basic instinct: to help each other out. If a hiker gets lost in the mountains, people will coordinate a search. If a train crashes, people will line up to give blood. If an earthquake levels a city, people all over the world will send emergency supplies. This is so fundamentally human that it's found in every culture without exception. Yes, there are assholes who just don't care, but they're massively outnumbered by the people who do. ~ Mark Watney, The Martian</h4>
</div>
I'm working on a website (that I didn't design, someone else gave me the HTML/CSS) as a developer and We've got a nice spinner animation for async loading components. It's forever-spinning animation is defined by this CSS rule:
animation: spinning 1s infinite linear; (it has also vendor prefix versions but it's irrelevant).
The spinning animation is defined as:
#keyframes spinning {
0% { transform: rotate(0); }
100% { transform: rotate(360deg); }
}
Our designer has put a position: absolute !important attribute to the spinning element. I was trying to position it inside some other element and I've thought that attribute was irrelevant. As soon as I removed position: absolute, the spinner stopped spinning. When I added it again, spinner started spinning again.
I've tried other position values too, it seems that absolute and fixed are working okay (in regards to spinning animation) while relative and static cause the animation to stop.
Why would CSS position attribute affect a spinner animation?
Here is a snippet reproducing the problem:
#keyframes spinning {
0% { transform: rotate(0); }
100% { transform: rotate(360deg); }
}
#first{
position: absolute;
}
#second{
position: relative; /* or don't specify it at all */
}
<div style='background:yellow;width:400px;height:100px;'>
<span id='first' style='animation:spinning 1s infinite linear'>hello</span>
</div>
<div style='background:lime;width:400px;height:100px;'>
<span id='second' style='animation:spinning 1s infinite linear'>hello</span>
</div>
It's because a span is an inline-element by default and so is not affected by transforms.
Setting the position to absolute imparts a block formatting to the span.
Just add display:inline-block:
#keyframes spinning {
0% {
transform: rotate(0);
}
100% {
transform: rotate(360deg);
}
}
div.one {
background: yellow;
width: 400px;
height: 100px;
}
div.two {
background: lime;
width: 400px;
height: 100px;
}
#first {
position: absolute;
animation: spinning 1s infinite linear
}
#second {
position: relative;
/* or don't specify it at all */
animation: spinning 1s infinite linear;
display: inline-block;
}
<div class="one">
<span id='first'>hello</span>
</div>
<div class="two">
<span id='second'>hello</span>
</div>