git.kianting.info Git - clo/blob - src/libclo/breakLines.js

   1 "use strict";
   2 Object.defineProperty(exports, "__esModule", { value: true });
   3 exports.totalCost = void 0;
   4 /**
   5  * Algorithms in LATEX language
   6 TotalCost(i) = min_{j}~TotalCost(j) + LineCost(j, i)~~~~j=0, 1, ..., i-1
   7
   8 LineCost(j, i)= \begin{cases}
   9 \infty ~~~ if~~LineWidth - \sum_{k=j+1}^{i-1} OrigWidth(item[k]) - newLineWidth(item[i]) < 0 \\
  10 \infty~~if~~NOT~~breakable(item[i]) \\
  11 (LineWidth - \sum_{k=j+1}^{i-1} OrigWidth(item[k]) - newLineWidth(item[i]))^3 ~~elsewhere
  12 \end{cases} */
  13 /**check if a boeitem is BreakPoint Type */
  14 function isBreakPoint(item) {
  15     return item.newLined !== undefined;
  16 }
  17 /**check if a boeitem is BreakPoint Type */
  18 function isHGlue(item) {
  19     return item.stretchFactor !== undefined;
  20 }
  21 /** measuring original advance width */
  22 function origWidth(item) {
  23     if (isBreakPoint(item)) {
  24         console.log(item);
  25         return origWidth(item.original);
  26     }
  27     else if (Array.isArray(item)) {
  28         return item.map((x) => origWidth(x))
  29             .reduce((acc, current) => acc + current, 0.0);
  30     }
  31     else if (isHGlue(item)) {
  32         return 0.0;
  33     }
  34     else {
  35         return item.width;
  36     }
  37 }
  38 /** measuring new-line triggered advance width */
  39 function newLineWidth(item) {
  40     if (isBreakPoint(item)) {
  41         return origWidth(item.newLined);
  42     }
  43     else {
  44         // impossible to make a new line
  45         return Infinity;
  46     }
  47 }
  48 let lineCostStorage = new Object();
  49 /**
  50  * check the total cost item[0..j].
  51  * @param items
  52  * @param i
  53  * @param lineWidth
  54  */
  55 function totalCost(items, j, lineWidth) {
  56     if (j in lineCostStorage) {
  57         return lineCostStorage[j];
  58     }
  59     var returnCost = Infinity;
  60     for (var i = -1; i <= j; i++) {
  61         // lineCost
  62         let lCost = lineCost(items, i, j, lineWidth);
  63         if (returnCost > lCost) {
  64             returnCost = lCost;
  65         }
  66     }
  67     lineCostStorage[j] = returnCost;
  68     return returnCost;
  69 }
  70 exports.totalCost = totalCost;
  71 /**
  72  * check the line cost of a line containing items[i+1..j]
  73  * @param items items of box
  74  * @param i beginning (excluded)
  75  * @param j end of the line
  76  * @param lineWidth line width
  77  */
  78 function lineCost(items, i, j, lineWidth) {
  79     if (!isBreakPoint(items[j])) {
  80         return Infinity;
  81     }
  82     else {
  83         var tmpItemWidth = 0;
  84         for (var k = i + 1; k < j; k++) {
  85             tmpItemWidth += origWidth(items[k]);
  86         }
  87         tmpItemWidth += newLineWidth(items[j]);
  88         if (tmpItemWidth > lineWidth) {
  89             return Infinity;
  90         }
  91         else {
  92             return (lineWidth - tmpItemWidth) ** 3.0;
  93         }
  94     }
  95 }