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Slightly optimized version of the ‘Device Scale UI elements in iOS Mobile Safari’ script by 37signals
// Provides a device_scale class on iOS devices for scaling user
// interface elements relative to the current zoom factor.
//
// http://37signals.com/svn/posts/2407-device-scale-user-interface-elements-in-ios-mobile-safari
// Copyright (c) 2010 37signals.
// Slightly optimized by Mathias Bynens <http://mathiasbynens.be/>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
(function(d, w) {
if (!('createTouch' in d)) return;
var headElement = d.head || d.getElementsByTagName('head')[0],
styleElement = d.createElement('style'),
stylesheet;
headElement.appendChild(styleElement);
stylesheet = styleElement.sheet;
w.addEventListener('scroll', updateDeviceScaleStyle, false);
w.addEventListener('resize', updateDeviceScaleStyle, false);
w.addEventListener('load', updateDeviceScaleStyle, false);
updateDeviceScaleStyle();
function updateDeviceScaleStyle() {
if (stylesheet.rules.length) {
stylesheet.deleteRule(0);
};
stylesheet.insertRule('.device-scale {-webkit-transform:scale(' + getDeviceScale() + ')}', 0);
};
// Adapted from code by Mislav Marohnić: http://gist.github.com/355625
function getDeviceScale() {
var landscape = Math.abs(window.orientation) === 90,
deviceWidth = landscape ? Math.max(480, screen.height) : screen.width; // iPhone OS < 3.2 reports a screen height of 396px
return w.innerWidth / deviceWidth;
};
})(document, window);
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