fastadmin/public/assets/libs/html2canvas/src/Renderer.js

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_html2canvas.Renderer = function(parseQueue, options){
// http://www.w3.org/TR/CSS21/zindex.html
function createRenderQueue(parseQueue) {
var queue = [],
rootContext;
rootContext = (function buildStackingContext(rootNode) {
var rootContext = {};
function insert(context, node, specialParent) {
var zi = (node.zIndex.zindex === 'auto') ? 0 : Number(node.zIndex.zindex),
contextForChildren = context, // the stacking context for children
isPositioned = node.zIndex.isPositioned,
isFloated = node.zIndex.isFloated,
stub = {node: node},
childrenDest = specialParent; // where children without z-index should be pushed into
if (node.zIndex.ownStacking) {
// '!' comes before numbers in sorted array
contextForChildren = stub.context = { '!': [{node:node, children: []}]};
childrenDest = undefined;
} else if (isPositioned || isFloated) {
childrenDest = stub.children = [];
}
if (zi === 0 && specialParent) {
specialParent.push(stub);
} else {
if (!context[zi]) { context[zi] = []; }
context[zi].push(stub);
}
node.zIndex.children.forEach(function(childNode) {
insert(contextForChildren, childNode, childrenDest);
});
}
insert(rootContext, rootNode);
return rootContext;
})(parseQueue);
function sortZ(context) {
Object.keys(context).sort().forEach(function(zi) {
var nonPositioned = [],
floated = [],
positioned = [],
list = [];
// positioned after static
context[zi].forEach(function(v) {
if (v.node.zIndex.isPositioned || v.node.zIndex.opacity < 1) {
// http://www.w3.org/TR/css3-color/#transparency
// non-positioned element with opactiy < 1 should be stacked as if it were a positioned element with z-index: 0 and opacity: 1.
positioned.push(v);
} else if (v.node.zIndex.isFloated) {
floated.push(v);
} else {
nonPositioned.push(v);
}
});
(function walk(arr) {
arr.forEach(function(v) {
list.push(v);
if (v.children) { walk(v.children); }
});
})(nonPositioned.concat(floated, positioned));
list.forEach(function(v) {
if (v.context) {
sortZ(v.context);
} else {
queue.push(v.node);
}
});
});
}
sortZ(rootContext);
return queue;
}
function getRenderer(rendererName) {
var renderer;
if (typeof options.renderer === "string" && _html2canvas.Renderer[rendererName] !== undefined) {
renderer = _html2canvas.Renderer[rendererName](options);
} else if (typeof rendererName === "function") {
renderer = rendererName(options);
} else {
throw new Error("Unknown renderer");
}
if ( typeof renderer !== "function" ) {
throw new Error("Invalid renderer defined");
}
return renderer;
}
return getRenderer(options.renderer)(parseQueue, options, document, createRenderQueue(parseQueue.stack), _html2canvas);
};