import { BmFont } from "./types.js";
export function measureText(font: BmFont, text: string) {
let x = 0;
for (let i = 0; i < text.length; i++) {
const char = text[i]!;
const fontChar = font.chars[char];
if (fontChar) {
const fontKerning = font.kernings[char];
const nextChar = text[i + 1];
const kerning =
fontKerning && nextChar && fontKerning[nextChar]
? fontKerning[nextChar] || 0
: 0;
x += (fontChar.xadvance || 0) + kerning;
}
}
return x;
}
export function splitLines(font: BmFont, text: string, maxWidth: number) {
const words = text.replace(/[\r\n]+/g, " \n").split(" ");
const lines: string[][] = [];
let currentLine: string[] = [];
let longestLine = 0;
words.forEach((word) => {
const wordWidth = measureText(font, word + (words.length > 1 ? " " : ""));
// If a word is longer than the allowable width we need to split it across lines.
if (wordWidth > maxWidth) {
const characterIterator = word[Symbol.iterator]();
let current = "";
for (const char of characterIterator) {
const nextLine = [...currentLine, current + char].join(" ");
const length = measureText(font, nextLine);
if (length < maxWidth) {
current += char;
} else if (length > maxWidth) {
lines.push([...currentLine, current]);
currentLine = [];
current = char;
} else {
lines.push([...currentLine, current + char]);
currentLine = [];
current = "";
}
}
return;
}
const line = [...currentLine, word].join(" ");
const length = measureText(font, line);
if (length <= maxWidth && !word.includes("\n")) {
if (length > longestLine) {
longestLine = length;
}
currentLine.push(word);
} else {
lines.push(currentLine);
currentLine = [word.replace("\n", "")];
}
});
lines.push(currentLine);
return {
lines,
longestLine,
};
}
export function measureTextHeight(
font: BmFont,
text: string,
maxWidth: number,
) {
const { lines } = splitLines(font, text, maxWidth);
return lines.length * font.common.lineHeight;
}
