p5.js: resize canvas height when div changes height - javascript

I'm trying to make the canvas with p5.js resize together with a div in which it is in when clicking on a button that extends this div giving it additional height. I don't need the canvas to reload, instead I just need it to add some additional height. Is there a way to do it? I tried making the canvas width 100% and height: auto, but it doesn't work. Please, see the code below:
<div class="canvas-wrapper">
<div id="canvas"></div>
</div>
<button type="button" class="button" id="extend-canvas">Extend</button>
Scripts:
function setup() {
var myCanvas = createCanvas(498, 598);
myCanvas.parent('canvas');
}
$( "#extend-canvas" ).click(function() {
var canvasHeight = $(".canvas-wrapper").height();
$(".canvas-wrapper").height(canvasHeight + 300);
});
CSS:
.canvas-wrapper {
margin: 0 auto;
background: #fff;
width: 500px;
height: 600px;
position: relative;
}
#canvas canvas {
width: 100% !important;
height: auto !important;
}

You can use the resizeCanvas() function for this. More info can be found in the reference.
Here's an example that resizes the canvas to match the screen width and height:
function setup() {
createCanvas(windowWidth, windowHeight);
}
function draw() {
background(0, 100, 200);
}
function windowResized() {
resizeCanvas(windowWidth, windowHeight);
}
But you could also get the width and height of the div and set the canvas size to that.

Related

why html5 canvas is not full screen when vertical scrollbar appears

I'm using a full screen canvas as background of the first section of my page. But as soon as I add the second section and vertical scrollbar appears, the height of canvas reduces a little bit and a gap appears. here's my code:
P.S: Sorry, my code contained bugs, I fixed them. now you can see the red gap.
var canvas = document.getElementById('canvas')
var c = canvas.getContext('2d')
scaleCanvas()
window.addEventListener("resize", scaleCanvas)
function scaleCanvas() {
canvas.width = window.innerWidth
canvas.height = window.innerHeight
c.fillStyle = 'black'
c.fillRect(0, 0, canvas.width, canvas.height)
}
* {
box-sizing: border-box;
max-width: 100%;
}
body {
margin: 0;
padding: 0;
}
#first-section {
position: relative;
min-height: 100vh;
background-color: red; /* to see the gap */
}
#content {
position: relative;
z-index: 2;
}
#second-section {
min-height: 100vh;
background-color: blue;
}
#canvas {
display: block;
padding: 0;
margin: 0;
border: none;
position: absolute;
top: 0;
left: 0;
z-index: 1;
}
<div id="first-section">
<canvas id="canvas"></canvas>
<div id="content">content</div>
</div>
<div id="second-section"></div>
Assuming you mean full screen, and not full page. The two are very different.
If you mean full page then the link to the Screen API will also give you details on obtaining the page size.
Size full screen canvas.
The problem is that you have content that extends outside the page width and height (innerWidth, innerHeight)
The elements with ids first-section, content, and second-section must be inside the display area or else you will get a scroll bar. The scroll bar will change the innerWidth, innerHeight values subtracting the scrollbar width or height depending on which is visible.
To prevent scroll bars the best option is to keep all content inside innerWidth, and innerHeight
Full screen with scroll bars.
If you want have the scroll bars and you are using full screen you can use the Screen API to get the width and height of the display in pixels. You can set the canvas size to match the screen without the scroll bars effecting its size.
Note Do read the provided link to Screen as what defines the screen may not be as expected. EG more than one monitor, or device orientation will effect how you use the API.
Basic example
Thus when in full-screen mode you can set the canvas size and ignore scroll bars with
function sizeFullScreenCanvas() {
canvas.width = screen.width;
canvas.height= screen.height;
}

How to move an image/div from right to left continuously?

What I'd like to do is animate a small image as well as a div (or an image within a div) from the right to the left of the screen, repeating once the image/div leaves the screen.
I found an example online that moves an image/div from left to right, but not all the way to the other side of the screen, and I am struggling to make it from right to left.
Here's what I have been doing
function moveTruck() {
$("#ImageToMove").animate({
"margin-right": "5000px"
}, 3000, function () { $("#ImageToMove").css("margin-right", "10000"); moveTruck(); });
}
moveTruck();
Playing with the margin-right values. My CSS class is:
.HomeImageAnimate{
position:absolute;
margin-top:80px;
right:1000px;
}
Try setting , animating left property using values of window.innerWidth , container element width
(function fx(el) {
$(el).css("left", window.innerWidth)
.animate({
left: "-" + (window.innerWidth - $(el).width() * 2)
}, 3000, "linear", function() {
fx(this)
})
}($("div")))
body {
overflow: hidden;
}
div {
width: 50px;
height: 50px;
position: absolute;
}
img {
background: gold;
width: 50px;
height: 50px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js">
</script>
<div>
<img />
</div>
Try this out, this truck div repeatedly goes from right to left.
HTML:
<div class="truck"></div>
CSS:
body{
background: green;
overflow: hidden;
}
.truck {
margin-top:20px;
width: 272px;
height: 174px;
cursor:pointer;
position: absolute;
margin-right: -150px;
z-index: 3;
background: red;
border-radius:4px;
width:200px;
height:50px;
}
JS:
$(function() {
var moveTruck = function(){
$(".truck").delay(2000).animate( {'right': '120%' }, 5000,'linear',function(){
$(this).css({'right': '-50px'});
moveTruck();
});
}
moveTruck();
})
CODEPEN DEMO
function move(){
width = $(window).width();
objectWidth = $('#demo').width();
margin = width + objectWidth + 'px';
restart = -100 - objectWidth + 'px';
$('#demo').animate({
'margin-left': margin
}, 3000, function(){
$('#demo').css('margin-left', restart);
move();
});
}
move();
Try this out, it calculates the exact width of object and window - should always work no matter the screen size. You were trying to use an absolute pixel value, won't always work.
https://jsfiddle.net/w9pgmm9d/3/

How to fill the browser window with a canvas element without creating scroll bars?

I have a problem to get my window size, I try this code:
Javascript
var game;
function game() {
this.canvas = document.getElementById('canvas');
this.canvasWidth = window.innerWidth;
this.canvasHeight = window.innerHeight;
this.initCanvas = function() {
this.canvas.style.width = this.canvasWidth + "px";
this.canvas.style.height = this.canvasHeight + "px";
}
this.run = function() {
this.initCanvas();
}
}
game = new game();
game.run();
I also have
CSS
html, body {
padding: 0;
margin: 0;
}
I only have a canvas in my body.
Problem is, that I have a vertical and horizontal scroll bar. This means the size of canvas is too large. How to make it of the window size without the scroll bars appearing?
It looks like you're just trying to make your canvas have a width and height of 100%. You can do this with just css:
HTML
<body>
<canvas id="canvas"></canvas>
</body>
CSS
body, html {
height: 100%;
width: 100%;
margin: 0px;
}
canvas {
background: #ffcccc;
height: 100%;
width: 100%;
display: block;
}
​
Demo
Or if you want to use your code but get rid of the scroll bars on the window, you need to specify block on the canvas tag.
CSS
canvas {
display: block;
}
Demo
When you use CSS to style your <canvas> element it will get scaled instead of sized. Be sure to set the .width and .height properties on the canvas element instead (ie canvas.width not canvas.style.width).
jsfiddle example
In the example the first canvas element is scaled correctly, the second (using CSS) is not scaled properly. This has to do with a default canvas element size (300x150) that CSS scales.
To prevent getting scrollbars when setting the <canvas> to the full window width/height set the body to overflow:hidden; as used in the jsfiddle above.

Create circle that is proportionately sized to window

I am attempting to create a circle with a height of 10% the browser window. If I also make the width 10%, and you scale the browser, you get a misshapen or squished circle. I want to try to create the width of the circle with jquery to change in proportion with the height. so if 10% converts to 200px height, the width would be changed to 200px. I have tried a few solutions, but keep getting a width of 0px in return.
assuming you are using jQuery and your circle is an HTML element you could do this:
var $window = $(window),
$el = $('#someElement');
$window.on('resize', function () {
var size = $window.height() * 0.1;
$el.width(size).height(size);
});
Get the width and the height of the window and then simply check which one of them is the smallest. Get 10% of that value and use this as the circle's radius.
Little experiment using a transparent square image which is the direct child of <body>:
http://jsfiddle.net/2S3xU/3/
<html><body><img src="transparent-square.gif">
img {
border-radius: 99999px;
position: absolute;
top: 0; left: 0;
height: 100%; /* width will follow height to keep image undistorted*/
max-width: 100%;
max-height: 10%;
}​
/* Opera fix*/
body, html {
width: 100%;
height: 100%;
}

Fabric.js changes my canvas size to 300x150 after initialization

HTML:
<div class="canvas-wrapper">
<canvas id="myCanvas"></canvas>
</div>
CSS
.canvas-wrapper {
width: 900px;
min-height: 600px;
}
#myCanvas{
border:1px solid red;
position: absolute;
top:22px;
left:0px;
height: 100%;
width: 99%;
}
JS
var myCanvas = new fabric.Canvas('myCanvas');
My canvas get resized to 300x150 after it's been initialized, why?
in the latest version, you will have to do something like:
var canvas = new fabric.Canvas('myCanvas');
canvas.setHeight(500);
canvas.setWidth(800);
.... Your code ....
canvas.renderAll();
Works fine for me..
For dynamically changing size, this works too
When initializing canvas, Fabric reads width/height attributes on canvas element or takes width/height passed in options.
var myCanvas = new fabric.Canvas('myCanvas', { width: 900, height: 600 });
or:
<canvas width="900" height="600"></canvas>
...
var myCanvas = new fabric.Canvas('myCanvas');
A real answer to this question—not involving a new static size but actually permitting CSS to be effective—is one of the following options:
In CSS, you can override individual properties and following them with !important; the downside to this is that any further definitions must also use !important or they will be ignored:
[width], [height], [style]
{
width: 100vw!important;
min-height: 100vh!important;
}
Using JQuery you can set the inline property values to an empty string. You can presumably achieve this without JQuery, but I will leave that as an exercise to you.
Javascript (JQuery):
$('[style]').attr( 'style', function(index, style){ return ''; });
$('[height]').attr( 'height', function(index, height){ return ''; });
$('[width]').attr( 'width', function(index, height){ return ''; });
CSS:
*, *:before, *:after
{
box-sizing: border-box;
}
body
{
width: 100vw;
min-height: 100vh;
padding: 0;
margin: 0;
}
.canvas-container,
canvas
{
width: inherit;
min-height: inherit;
}
canvas.lower-canvas
{
position: absolute;
top: 0;
}
After that, CSS will be applied as expected.
It is apparently also necessary to tell Fabric about the change:
function sizeCanvas()
{
var width = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
var height = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
canvas.setHeight( height )
canvas.setWidth( width )
}
window.addEventListener('resize', draw, false);
function initDraw()
{
// setup
}
function draw()
{
canvas.renderAll();
}
sizeCanvas();
initDraw();
This will configure Fabric to the viewport size and keep it sized accordingly if it resizes.
It's worth noting that this problem arises for two reasons:
Someone thought it was a good idea to use inline styles and should be severely castigated, as there is no situation where this is ever an appropriate practice.
Fabric changes the DOM arrangement and nests the original canvas in a new div with a second nested canvas, which may result in surprises.

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