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author | Christopher Speller <crspeller@gmail.com> | 2016-03-14 08:50:46 -0400 |
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committer | Christopher Speller <crspeller@gmail.com> | 2016-03-16 18:02:55 -0400 |
commit | 12896bd23eeba79884245c1c29fdc568cf21a7fa (patch) | |
tree | 4e7f83d3e2564b9b89d669e9f7905ff11768b11a /webapp/non_npm_dependencies/katex/src/buildCommon.js | |
parent | 29fe6a3d13c9c7aa490fffebbe5d1b5fdf1e3090 (diff) | |
download | chat-12896bd23eeba79884245c1c29fdc568cf21a7fa.tar.gz chat-12896bd23eeba79884245c1c29fdc568cf21a7fa.tar.bz2 chat-12896bd23eeba79884245c1c29fdc568cf21a7fa.zip |
Converting to Webpack. Stage 1.
Diffstat (limited to 'webapp/non_npm_dependencies/katex/src/buildCommon.js')
-rw-r--r-- | webapp/non_npm_dependencies/katex/src/buildCommon.js | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/webapp/non_npm_dependencies/katex/src/buildCommon.js b/webapp/non_npm_dependencies/katex/src/buildCommon.js new file mode 100644 index 000000000..b60e1860a --- /dev/null +++ b/webapp/non_npm_dependencies/katex/src/buildCommon.js @@ -0,0 +1,450 @@ +/* eslint no-console:0 */ +/** + * This module contains general functions that can be used for building + * different kinds of domTree nodes in a consistent manner. + */ + +var domTree = require("./domTree"); +var fontMetrics = require("./fontMetrics"); +var symbols = require("./symbols"); +var utils = require("./utils"); + +var greekCapitals = [ + "\\Gamma", + "\\Delta", + "\\Theta", + "\\Lambda", + "\\Xi", + "\\Pi", + "\\Sigma", + "\\Upsilon", + "\\Phi", + "\\Psi", + "\\Omega", +]; + +var dotlessLetters = [ + "\u0131", // dotless i, \imath + "\u0237", // dotless j, \jmath +]; + +/** + * Makes a symbolNode after translation via the list of symbols in symbols.js. + * Correctly pulls out metrics for the character, and optionally takes a list of + * classes to be attached to the node. + */ +var makeSymbol = function(value, style, mode, color, classes) { + // Replace the value with its replaced value from symbol.js + if (symbols[mode][value] && symbols[mode][value].replace) { + value = symbols[mode][value].replace; + } + + var metrics = fontMetrics.getCharacterMetrics(value, style); + + var symbolNode; + if (metrics) { + symbolNode = new domTree.symbolNode( + value, metrics.height, metrics.depth, metrics.italic, metrics.skew, + classes); + } else { + // TODO(emily): Figure out a good way to only print this in development + typeof console !== "undefined" && console.warn( + "No character metrics for '" + value + "' in style '" + + style + "'"); + symbolNode = new domTree.symbolNode(value, 0, 0, 0, 0, classes); + } + + if (color) { + symbolNode.style.color = color; + } + + return symbolNode; +}; + +/** + * Makes a symbol in Main-Regular or AMS-Regular. + * Used for rel, bin, open, close, inner, and punct. + */ +var mathsym = function(value, mode, color, classes) { + // Decide what font to render the symbol in by its entry in the symbols + // table. + // Have a special case for when the value = \ because the \ is used as a + // textord in unsupported command errors but cannot be parsed as a regular + // text ordinal and is therefore not present as a symbol in the symbols + // table for text + if (value === "\\" || symbols[mode][value].font === "main") { + return makeSymbol(value, "Main-Regular", mode, color, classes); + } else { + return makeSymbol( + value, "AMS-Regular", mode, color, classes.concat(["amsrm"])); + } +}; + +/** + * Makes a symbol in the default font for mathords and textords. + */ +var mathDefault = function(value, mode, color, classes, type) { + if (type === "mathord") { + return mathit(value, mode, color, classes); + } else if (type === "textord") { + return makeSymbol( + value, "Main-Regular", mode, color, classes.concat(["mathrm"])); + } else { + throw new Error("unexpected type: " + type + " in mathDefault"); + } +}; + +/** + * Makes a symbol in the italic math font. + */ +var mathit = function(value, mode, color, classes) { + if (/[0-9]/.test(value.charAt(0)) || + // glyphs for \imath and \jmath do not exist in Math-Italic so we + // need to use Main-Italic instead + utils.contains(dotlessLetters, value) || + utils.contains(greekCapitals, value)) { + return makeSymbol( + value, "Main-Italic", mode, color, classes.concat(["mainit"])); + } else { + return makeSymbol( + value, "Math-Italic", mode, color, classes.concat(["mathit"])); + } +}; + +/** + * Makes either a mathord or textord in the correct font and color. + */ +var makeOrd = function(group, options, type) { + var mode = group.mode; + var value = group.value; + if (symbols[mode][value] && symbols[mode][value].replace) { + value = symbols[mode][value].replace; + } + + var classes = ["mord"]; + var color = options.getColor(); + + var font = options.font; + if (font) { + if (font === "mathit" || utils.contains(dotlessLetters, value)) { + return mathit(value, mode, color, classes); + } else { + var fontName = fontMap[font].fontName; + if (fontMetrics.getCharacterMetrics(value, fontName)) { + return makeSymbol( + value, fontName, mode, color, classes.concat([font])); + } else { + return mathDefault(value, mode, color, classes, type); + } + } + } else { + return mathDefault(value, mode, color, classes, type); + } +}; + +/** + * Calculate the height, depth, and maxFontSize of an element based on its + * children. + */ +var sizeElementFromChildren = function(elem) { + var height = 0; + var depth = 0; + var maxFontSize = 0; + + if (elem.children) { + for (var i = 0; i < elem.children.length; i++) { + if (elem.children[i].height > height) { + height = elem.children[i].height; + } + if (elem.children[i].depth > depth) { + depth = elem.children[i].depth; + } + if (elem.children[i].maxFontSize > maxFontSize) { + maxFontSize = elem.children[i].maxFontSize; + } + } + } + + elem.height = height; + elem.depth = depth; + elem.maxFontSize = maxFontSize; +}; + +/** + * Makes a span with the given list of classes, list of children, and color. + */ +var makeSpan = function(classes, children, color) { + var span = new domTree.span(classes, children); + + sizeElementFromChildren(span); + + if (color) { + span.style.color = color; + } + + return span; +}; + +/** + * Makes a document fragment with the given list of children. + */ +var makeFragment = function(children) { + var fragment = new domTree.documentFragment(children); + + sizeElementFromChildren(fragment); + + return fragment; +}; + +/** + * Makes an element placed in each of the vlist elements to ensure that each + * element has the same max font size. To do this, we create a zero-width space + * with the correct font size. + */ +var makeFontSizer = function(options, fontSize) { + var fontSizeInner = makeSpan([], [new domTree.symbolNode("\u200b")]); + fontSizeInner.style.fontSize = + (fontSize / options.style.sizeMultiplier) + "em"; + + var fontSizer = makeSpan( + ["fontsize-ensurer", "reset-" + options.size, "size5"], + [fontSizeInner]); + + return fontSizer; +}; + +/** + * Makes a vertical list by stacking elements and kerns on top of each other. + * Allows for many different ways of specifying the positioning method. + * + * Arguments: + * - children: A list of child or kern nodes to be stacked on top of each other + * (i.e. the first element will be at the bottom, and the last at + * the top). Element nodes are specified as + * {type: "elem", elem: node} + * while kern nodes are specified as + * {type: "kern", size: size} + * - positionType: The method by which the vlist should be positioned. Valid + * values are: + * - "individualShift": The children list only contains elem + * nodes, and each node contains an extra + * "shift" value of how much it should be + * shifted (note that shifting is always + * moving downwards). positionData is + * ignored. + * - "top": The positionData specifies the topmost point of + * the vlist (note this is expected to be a height, + * so positive values move up) + * - "bottom": The positionData specifies the bottommost point + * of the vlist (note this is expected to be a + * depth, so positive values move down + * - "shift": The vlist will be positioned such that its + * baseline is positionData away from the baseline + * of the first child. Positive values move + * downwards. + * - "firstBaseline": The vlist will be positioned such that + * its baseline is aligned with the + * baseline of the first child. + * positionData is ignored. (this is + * equivalent to "shift" with + * positionData=0) + * - positionData: Data used in different ways depending on positionType + * - options: An Options object + * + */ +var makeVList = function(children, positionType, positionData, options) { + var depth; + var currPos; + var i; + if (positionType === "individualShift") { + var oldChildren = children; + children = [oldChildren[0]]; + + // Add in kerns to the list of children to get each element to be + // shifted to the correct specified shift + depth = -oldChildren[0].shift - oldChildren[0].elem.depth; + currPos = depth; + for (i = 1; i < oldChildren.length; i++) { + var diff = -oldChildren[i].shift - currPos - + oldChildren[i].elem.depth; + var size = diff - + (oldChildren[i - 1].elem.height + + oldChildren[i - 1].elem.depth); + + currPos = currPos + diff; + + children.push({type: "kern", size: size}); + children.push(oldChildren[i]); + } + } else if (positionType === "top") { + // We always start at the bottom, so calculate the bottom by adding up + // all the sizes + var bottom = positionData; + for (i = 0; i < children.length; i++) { + if (children[i].type === "kern") { + bottom -= children[i].size; + } else { + bottom -= children[i].elem.height + children[i].elem.depth; + } + } + depth = bottom; + } else if (positionType === "bottom") { + depth = -positionData; + } else if (positionType === "shift") { + depth = -children[0].elem.depth - positionData; + } else if (positionType === "firstBaseline") { + depth = -children[0].elem.depth; + } else { + depth = 0; + } + + // Make the fontSizer + var maxFontSize = 0; + for (i = 0; i < children.length; i++) { + if (children[i].type === "elem") { + maxFontSize = Math.max(maxFontSize, children[i].elem.maxFontSize); + } + } + var fontSizer = makeFontSizer(options, maxFontSize); + + // Create a new list of actual children at the correct offsets + var realChildren = []; + currPos = depth; + for (i = 0; i < children.length; i++) { + if (children[i].type === "kern") { + currPos += children[i].size; + } else { + var child = children[i].elem; + + var shift = -child.depth - currPos; + currPos += child.height + child.depth; + + var childWrap = makeSpan([], [fontSizer, child]); + childWrap.height -= shift; + childWrap.depth += shift; + childWrap.style.top = shift + "em"; + + realChildren.push(childWrap); + } + } + + // Add in an element at the end with no offset to fix the calculation of + // baselines in some browsers (namely IE, sometimes safari) + var baselineFix = makeSpan( + ["baseline-fix"], [fontSizer, new domTree.symbolNode("\u200b")]); + realChildren.push(baselineFix); + + var vlist = makeSpan(["vlist"], realChildren); + // Fix the final height and depth, in case there were kerns at the ends + // since the makeSpan calculation won't take that in to account. + vlist.height = Math.max(currPos, vlist.height); + vlist.depth = Math.max(-depth, vlist.depth); + return vlist; +}; + +// A table of size -> font size for the different sizing functions +var sizingMultiplier = { + size1: 0.5, + size2: 0.7, + size3: 0.8, + size4: 0.9, + size5: 1.0, + size6: 1.2, + size7: 1.44, + size8: 1.73, + size9: 2.07, + size10: 2.49, +}; + +// A map of spacing functions to their attributes, like size and corresponding +// CSS class +var spacingFunctions = { + "\\qquad": { + size: "2em", + className: "qquad", + }, + "\\quad": { + size: "1em", + className: "quad", + }, + "\\enspace": { + size: "0.5em", + className: "enspace", + }, + "\\;": { + size: "0.277778em", + className: "thickspace", + }, + "\\:": { + size: "0.22222em", + className: "mediumspace", + }, + "\\,": { + size: "0.16667em", + className: "thinspace", + }, + "\\!": { + size: "-0.16667em", + className: "negativethinspace", + }, +}; + +/** + * Maps TeX font commands to objects containing: + * - variant: string used for "mathvariant" attribute in buildMathML.js + * - fontName: the "style" parameter to fontMetrics.getCharacterMetrics + */ +// A map between tex font commands an MathML mathvariant attribute values +var fontMap = { + // styles + "mathbf": { + variant: "bold", + fontName: "Main-Bold", + }, + "mathrm": { + variant: "normal", + fontName: "Main-Regular", + }, + + // "mathit" is missing because it requires the use of two fonts: Main-Italic + // and Math-Italic. This is handled by a special case in makeOrd which ends + // up calling mathit. + + // families + "mathbb": { + variant: "double-struck", + fontName: "AMS-Regular", + }, + "mathcal": { + variant: "script", + fontName: "Caligraphic-Regular", + }, + "mathfrak": { + variant: "fraktur", + fontName: "Fraktur-Regular", + }, + "mathscr": { + variant: "script", + fontName: "Script-Regular", + }, + "mathsf": { + variant: "sans-serif", + fontName: "SansSerif-Regular", + }, + "mathtt": { + variant: "monospace", + fontName: "Typewriter-Regular", + }, +}; + +module.exports = { + fontMap: fontMap, + makeSymbol: makeSymbol, + mathsym: mathsym, + makeSpan: makeSpan, + makeFragment: makeFragment, + makeVList: makeVList, + makeOrd: makeOrd, + sizingMultiplier: sizingMultiplier, + spacingFunctions: spacingFunctions, +}; |