Implement justifying for unicode fonts (#3285)

Co-authored-by: Lukas Holländer <lukas.hollaender@yworks.com>

Author: owenl131

src/jspdf.js

@@ -3806,23 +3806,23 @@ function jsPDF(options) {
  flags = Object.assign({ autoencode: true, noBOM: true }, options.flags);
 
  var wordSpacingPerLine = [];
-
+ var findWidth = function(v) {
+ return (
+ (scope.getStringUnitWidth(v, {
+ font: activeFont,
+ charSpace: charSpace,
+ fontSize: activeFontSize,
+ doKerning: false
+ }) *
+ activeFontSize) /
+ scaleFactor
+ );
+ };
  if (Object.prototype.toString.call(text) === "[object Array]") {
  da = transformTextToSpecialArray(text);
  var newY;
  if (align !== "left") {
- lineWidths = da.map(function(v) {
- return (
- (scope.getStringUnitWidth(v, {
- font: activeFont,
- charSpace: charSpace,
- fontSize: activeFontSize,
- doKerning: false
- }) *
- activeFontSize) /
- scaleFactor
- );
- });
+ lineWidths = da.map(findWidth);
  }
  //The first line uses the "main" Td setting,
  //and the subsequent lines are offset by the
@@ -3869,11 +3869,41 @@ function jsPDF(options) {
  for (var h = 0; h < len; h++) {
  text.push(da[h]);
  }
+ } else if (align === "justify" && activeFont.encoding === "Identity-H") {
+ // when using unicode fonts, wordSpacePerLine does not apply
+ text = [];
+ len = da.length;
+ maxWidth = maxWidth !== 0 ? maxWidth : pageWidth;
+ let backToStartX = 0;
+ for (var l = 0; l < len; l++) {
+ newY = l === 0 ? getVerticalCoordinate(y) : -leading;
+ newX = l === 0 ? getHorizontalCoordinate(x) : backToStartX;
+ if (l < len - 1) {
+ let spacing = scale(
+ (maxWidth - lineWidths[l]) / (da[l].split(" ").length - 1)
+ );
+ let words = da[l].split(" ");
+ text.push([words[0] + " ", newX, newY]);
+ backToStartX = 0; // distance to reset back to the left
+ for (let i = 1; i < words.length; i++) {
+ let shiftAmount =
+ (findWidth(words[i - 1] + " " + words[i]) -
+ findWidth(words[i])) *
+ scaleFactor +
+ spacing;
+ if (i == words.length - 1) text.push([words[i], shiftAmount, 0]);
+ else text.push([words[i] + " ", shiftAmount, 0]);
+ backToStartX -= shiftAmount;
+ }
+ } else {
+ text.push([da[l], newX, newY]);
+ }
+ }
+ text.push(["", backToStartX, 0]);
  } else if (align === "justify") {
  text = [];
  len = da.length;
  maxWidth = maxWidth !== 0 ? maxWidth : pageWidth;
-
  for (var l = 0; l < len; l++) {
  newY = l === 0 ? getVerticalCoordinate(y) : -leading;
  newX = l === 0 ? getHorizontalCoordinate(x) : 0;

test/reference/justify-custom-font.pdf

@@ -175,6 +175,25 @@ break`
  comparePdf(doc.output(), "alignment.pdf", "text");
  });
 
+ it("should justify custom font", () => {
+ const doc = jsPDF({ floatPrecision: 2 });
+ var PTSans;
+ if (typeof global === "object" && global.isNode === true) {
+ PTSans = doc.loadFile("./test/reference/PTSans.ttf");
+ } else {
+ PTSans = doc.loadFile("base/test/reference/PTSans.ttf");
+ }
+ doc.addFileToVFS("PTSans.ttf", PTSans);
+ doc.addFont("PTSans.ttf", "PTSans", "normal");
+ doc.setFont("PTSans");
+ doc.setFontSize(10);
+ doc.text("А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! А ну чики брики и в дамки! ", 10, 10, {
+ align: "justify",
+ maxWidth: 100,
+ });
+ comparePdf(doc.output(), "justify-custom-font.pdf", "text");
+ });
+
  it("should throw an error if not a string", () => {
  expect(() => {
  const doc = jsPDF({ floatPrecision: 2 });