/*----------------------------------------
* objectFitPolyfill 2.3.5
*
* Made by Constance Chen
* Released under the ISC license
*
* https://github.com/constancecchen/object-fit-polyfill
*--------------------------------------*/
(function() {
'use strict';
// if the page is being rendered on the server, don't continue
if (typeof window === 'undefined') return;
// Workaround for Edge 16-18, which only implemented object-fit for <img> tags
var edgeMatch = window.navigator.userAgent.match(/Edge\/(\d{2})\./);
var edgeVersion = edgeMatch ? parseInt(edgeMatch[1], 10) : null;
var edgePartialSupport = edgeVersion
? edgeVersion >= 16 && edgeVersion <= 18
: false;
// If the browser does support object-fit, we don't need to continue
var hasSupport = 'objectFit' in document.documentElement.style !== false;
if (hasSupport && !edgePartialSupport) {
window.objectFitPolyfill = function() {
return false;
};
return;
}
/**
* Check the container's parent element to make sure it will
* correctly handle and clip absolutely positioned children
*
* @param {node} $container - parent element
*/
var checkParentContainer = function($container) {
var styles = window.getComputedStyle($container, null);
var position = styles.getPropertyValue('position');
var overflow = styles.getPropertyValue('overflow');
var display = styles.getPropertyValue('display');
if (!position || position === 'static') {
$container.style.position = 'relative';
}
if (overflow !== 'hidden') {
$container.style.overflow = 'hidden';
}
// Guesstimating that people want the parent to act like full width/height wrapper here.
// Mostly attempts to target <picture> elements, which default to inline.
if (!display || display === 'inline') {
$container.style.display = 'block';
}
if ($container.clientHeight === 0) {
$container.style.height = '100%';
}
// Add a CSS class hook, in case people need to override styles for any reason.
if ($container.className.indexOf('object-fit-polyfill') === -1) {
$container.className = $container.className + ' object-fit-polyfill';
}
};
/**
* Check for pre-set max-width/height, min-width/height,
* positioning, or margins, which can mess up image calculations
*
* @param {node} $media - img/video element
*/
var checkMediaProperties = function($media) {
var styles = window.getComputedStyle($media, null);
var constraints = {
'max-width': 'none',
'max-height': 'none',
'min-width': '0px',
'min-height': '0px',
top: 'auto',
right: 'auto',
bottom: 'auto',
left: 'auto',
'margin-top': '0px',
'margin-right': '0px',
'margin-bottom': '0px',
'margin-left': '0px',
};
for (var property in constraints) {
var constraint = styles.getPropertyValue(property);
if (constraint !== constraints[property]) {
$media.style[property] = constraints[property];
}
}
};
/**
* Calculate & set object-position
*
* @param {string} axis - either "x" or "y"
* @param {node} $media - img or video element
* @param {string} objectPosition - e.g. "50% 50%", "top left"
*/
var setPosition = function(axis, $media, objectPosition) {
var position, other, start, end, side;
objectPosition = objectPosition.split(' ');
if (objectPosition.length < 2) {
objectPosition[1] = objectPosition[0];
}
/* istanbul ignore else */
if (axis === 'x') {
position = objectPosition[0];
other = objectPosition[1];
start = 'left';
end = 'right';
side = $media.clientWidth;
} else if (axis === 'y') {
position = objectPosition[1];
other = objectPosition[0];
start = 'top';
end = 'bottom';
side = $media.clientHeight;
} else {
return; // Neither x or y axis specified
}
if (position === start || other === start) {
$media.style[start] = '0';
return;
}
if (position === end || other === end) {
$media.style[end] = '0';
return;
}
if (position === 'center' || position === '50%') {
$media.style[start] = '50%';
$media.style['margin-' + start] = side / -2 + 'px';
return;
}
// Percentage values (e.g., 30% 10%)
if (position.indexOf('%') >= 0) {
position = parseInt(position, 10);
if (position < 50) {
$media.style[start] = position + '%';
$media.style['margin-' + start] = side * (position / -100) + 'px';
} else {
position = 100 - position;
$media.style[end] = position + '%';
$media.style['margin-' + end] = side * (position / -100) + 'px';
}
return;
}
// Length-based values (e.g. 10px / 10em)
else {
$media.style[start] = position;
}
};
/**
* Calculate & set object-fit
*
* @param {node} $media - img/video/picture element
*/
var objectFit = function($media) {
// IE 10- data polyfill
var fit = $media.dataset
? $media.dataset.objectFit
: $media.getAttribute('data-object-fit');
var position = $media.dataset
? $media.dataset.objectPosition
: $media.getAttribute('data-object-position');
// Default fallbacks
fit = fit || 'cover';
position = position || '50% 50%';
// If necessary, make the parent container work with absolutely positioned elements
var $container = $media.parentNode;
checkParentContainer($container);
// Check for any pre-set CSS which could mess up image calculations
checkMediaProperties($media);
// Reset any pre-set width/height CSS and handle fit positioning
$media.style.position = 'absolute';
$media.style.width = 'auto';
$media.style.height = 'auto';
// `scale-down` chooses either `none` or `contain`, whichever is smaller
if (fit === 'scale-down') {
if (
$media.clientWidth < $container.clientWidth &&
$media.clientHeight < $container.clientHeight
) {
fit = 'none';
} else {
fit = 'contain';
}
}
// `none` (width/height auto) and `fill` (100%) and are straightforward
if (fit === 'none') {
setPosition('x', $media, position);
setPosition('y', $media, position);
return;
}
if (fit === 'fill') {
$media.style.width = '100%';
$media.style.height = '100%';
setPosition('x', $media, position);
setPosition('y', $media, position);
return;
}
// `cover` and `contain` must figure out which side needs covering, and add CSS positioning & centering
$media.style.height = '100%';
if (
(fit === 'cover' && $media.clientWidth > $container.clientWidth) ||
(fit === 'contain' && $media.clientWidth < $container.clientWidth)
) {
$media.style.top = '0';
$media.style.marginTop = '0';
setPosition('x', $media, position);
} else {
$media.style.width = '100%';
$media.style.height = 'auto';
$media.style.left = '0';
$media.style.marginLeft = '0';
setPosition('y', $media, position);
}
};
/**
* Initialize plugin
*
* @param {node} media - Optional specific DOM node(s) to be polyfilled
*/
var objectFitPolyfill = function(media) {
if (typeof media === 'undefined' || media instanceof Event) {
// If left blank, or a default event, all media on the page will be polyfilled.
media = document.querySelectorAll('[data-object-fit]');
} else if (media && media.nodeName) {
// If it's a single node, wrap it in an array so it works.
media = [media];
} else if (typeof media === 'object' && media.length && media[0].nodeName) {
// If it's an array of DOM nodes (e.g. a jQuery selector), it's fine as-is.
media = media;
} else {
// Otherwise, if it's invalid or an incorrect type, return false to let people know.
return false;
}
for (var i = 0; i < media.length; i++) {
if (!media[i].nodeName) continue;
var mediaType = media[i].nodeName.toLowerCase();
if (mediaType === 'img') {
if (edgePartialSupport) continue; // Edge supports object-fit for images (but nothing else), so no need to polyfill
if (media[i].complete) {
objectFit(media[i]);
} else {
media[i].addEventListener('load', function() {
objectFit(this);
});
}
} else if (mediaType === 'video') {
if (media[i].readyState > 0) {
objectFit(media[i]);
} else {
media[i].addEventListener('loadedmetadata', function() {
objectFit(this);
});
}
} else {
objectFit(media[i]);
}
}
return true;
};
if (document.readyState === 'loading') {
// Loading hasn't finished yet
document.addEventListener('DOMContentLoaded', objectFitPolyfill);
} else {
// `DOMContentLoaded` has already fired
objectFitPolyfill();
}
window.addEventListener('resize', objectFitPolyfill);
window.objectFitPolyfill = objectFitPolyfill;
})();
في هذا التقرير المصور، نأخذك في جولة بصرية داخل عالم ألعاب الواقع الافتراضي (VR)، حيث تندمج التكنولوجيا مع الترفيه لخلق تجارب لا مثيل لها. من خلال نظارات الواقع الافتراضي المتطورة، يمكن للاعبين التفاعل مع بيئات ثلاثية الأبعاد، مما يتيح لهم الانغماس الكامل في الألعاب. سنستعرض أبرز الألعاب المتاحة، مثل “Beat Saber” و”Half-Life: Alyx”، التي تقدم تجارب تفاعلية مبتكرة. كما نسلط الضوء على التحديات التي تواجه هذه التقنية، مثل التكلفة المرتفعة ومشاكل الراحة أثناء الاستخدام الطويل. انضم إلينا لاكتشاف كيف يُعيد الواقع الافتراضي تعريف مفهوم اللعب ويشكل مستقبل صناعة الألعاب.
