alpaca
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Alpaca provides the easiest and fastest way to generate interactive forms for the web and mobile devices. It runs simply as HTML5 or more elaborately using Bootstrap, jQuery Mobile or jQuery UI. Alpaca uses Handlebars to process JSON schema and provide
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JavaScript
/*
* JavaScript Load Image Orientation 1.1.0
* https://github.com/blueimp/JavaScript-Load-Image
*
* Copyright 2013, Sebastian Tschan
* https://blueimp.net
*
* Licensed under the MIT license:
* http://www.opensource.org/licenses/MIT
*/
/*global define, window */
(function (factory) {
'use strict';
if (typeof define === 'function' && define.amd) {
// Register as an anonymous AMD module:
define(['load-image'], factory);
} else {
// Browser globals:
factory(window.loadImage);
}
}(function (loadImage) {
'use strict';
var originalHasCanvasOption = loadImage.hasCanvasOption,
originalTransformCoordinates = loadImage.transformCoordinates,
originalGetTransformedOptions = loadImage.getTransformedOptions;
// This method is used to determine if the target image
// should be a canvas element:
loadImage.hasCanvasOption = function (options) {
return originalHasCanvasOption.call(loadImage, options) ||
options.orientation;
};
// Transform image orientation based on
// the given EXIF orientation option:
loadImage.transformCoordinates = function (canvas, options) {
originalTransformCoordinates.call(loadImage, canvas, options);
var ctx = canvas.getContext('2d'),
width = canvas.width,
height = canvas.height,
orientation = options.orientation;
if (!orientation || orientation > 8) {
return;
}
if (orientation > 4) {
canvas.width = height;
canvas.height = width;
}
switch (orientation) {
case 2:
// horizontal flip
ctx.translate(width, 0);
ctx.scale(-1, 1);
break;
case 3:
// 180° rotate left
ctx.translate(width, height);
ctx.rotate(Math.PI);
break;
case 4:
// vertical flip
ctx.translate(0, height);
ctx.scale(1, -1);
break;
case 5:
// vertical flip + 90 rotate right
ctx.rotate(0.5 * Math.PI);
ctx.scale(1, -1);
break;
case 6:
// 90° rotate right
ctx.rotate(0.5 * Math.PI);
ctx.translate(0, -height);
break;
case 7:
// horizontal flip + 90 rotate right
ctx.rotate(0.5 * Math.PI);
ctx.translate(width, -height);
ctx.scale(-1, 1);
break;
case 8:
// 90° rotate left
ctx.rotate(-0.5 * Math.PI);
ctx.translate(-width, 0);
break;
}
};
// Transforms coordinate and dimension options
// based on the given orientation option:
loadImage.getTransformedOptions = function (img, opts) {
var options = originalGetTransformedOptions.call(loadImage, img, opts),
orientation = options.orientation,
newOptions,
i;
if (!orientation || orientation > 8 || orientation === 1) {
return options;
}
newOptions = {};
for (i in options) {
if (options.hasOwnProperty(i)) {
newOptions[i] = options[i];
}
}
switch (options.orientation) {
case 2:
// horizontal flip
newOptions.left = options.right;
newOptions.right = options.left;
break;
case 3:
// 180° rotate left
newOptions.left = options.right;
newOptions.top = options.bottom;
newOptions.right = options.left;
newOptions.bottom = options.top;
break;
case 4:
// vertical flip
newOptions.top = options.bottom;
newOptions.bottom = options.top;
break;
case 5:
// vertical flip + 90 rotate right
newOptions.left = options.top;
newOptions.top = options.left;
newOptions.right = options.bottom;
newOptions.bottom = options.right;
break;
case 6:
// 90° rotate right
newOptions.left = options.top;
newOptions.top = options.right;
newOptions.right = options.bottom;
newOptions.bottom = options.left;
break;
case 7:
// horizontal flip + 90 rotate right
newOptions.left = options.bottom;
newOptions.top = options.right;
newOptions.right = options.top;
newOptions.bottom = options.left;
break;
case 8:
// 90° rotate left
newOptions.left = options.bottom;
newOptions.top = options.left;
newOptions.right = options.top;
newOptions.bottom = options.right;
break;
}
if (options.orientation > 4) {
newOptions.maxWidth = options.maxHeight;
newOptions.maxHeight = options.maxWidth;
newOptions.minWidth = options.minHeight;
newOptions.minHeight = options.minWidth;
newOptions.sourceWidth = options.sourceHeight;
newOptions.sourceHeight = options.sourceWidth;
}
return newOptions;
};
}));