splat-ecs/lib/font-loader.js

A 2D HTML5 Canvas game engine

require("../vendor/FontLoader.js");
var platform = require("./platform");

function buildFontFaceRule(family, urls) {
  var eot = urls["embedded-opentype"];
  var woff = urls.woff;
  var ttf = urls.truetype;
  var svg = urls.svg;

  var css = "\n";
  css += "@font-face {\n";
  css += "  font-family: \"" + family + "\";\n";
  css += "  src: url(\"" + eot + "\");\n";
  css += "  src: url(\"" + eot + "?iefix\") format(\"embedded-opentype\"),\n";
  css += "       url(\"" + woff + "\") format(\"woff\"),\n";
  css += "       url(\"" + ttf + "\") format(\"ttf\"),\n";
  css += "       url(\"" + svg + "\") format(\"svg\");\n";
  css += "}\n";
  return css;
}

function createCssFontFaces(fontFamilies) {
  var style = document.createElement("style");
  style.setAttribute("type", "text/css");
  var css = "";
  for (var family in fontFamilies) {
    if (fontFamilies.hasOwnProperty(family)) {
      css += buildFontFaceRule(family, fontFamilies[family]);
    }
  }
  style.appendChild(document.createTextNode(css));
  document.head.appendChild(style);
}

/**
 * Load fonts and lets you know when they're all available. An instance of FontLoader is available as {@link Splat.Game#fonts}.
 * @constructor
 */
function FontLoader() {
  /**
   * The total number of fonts to be loaded.
   * @member {number}
   * @private
   */
  this.totalFonts = 0;
  /**
   * The number of fonts that have loaded completely.
   * @member {number}
   * @private
   */
  this.loadedFonts = 0;
}
/**
 * Load a font.
 * @param {object} fontFamilies A key-value object that maps css font-family names to another object that holds paths to the various font files in different formats.
 * @example
 game.fonts.load({
 "pixelade": {
 "embedded-opentype": "pixelade/pixelade-webfont.eot",
 "woff": "pixelade/pixelade-webfont.woff",
 "truetype": "pixelade/pixelade-webfont.ttf",
 "svg": "pixelade/pixelade-webfont.svg#pixeladeregular"
 }
 });
 */
FontLoader.prototype.load = function(fontFamilies) {
  createCssFontFaces(fontFamilies);

  var families = [];
  for (var family in fontFamilies) {
    if (families.hasOwnProperty(family)) {
      families.push(family);
    }
  }
  this.totalFonts += families.length;

  var self = this;
  var loader = new window.FontLoader(families, {
    "fontLoaded": function() {
      self.loadedFonts++;
    }
  });
  loader.loadFonts();
};
/**
 * Test if all font fonts have loaded.
 * @returns {boolean}
 */
FontLoader.prototype.allLoaded = function() {
  return this.totalFonts === this.loadedFonts;
};

/**
 * An alternate {@link FontLoader} when the game is running inside [Ejecta]{@link http://impactjs.com/ejecta}. You shouldn't need to worry about this.
 * @constructor
 * @private
 */
function EjectaFontLoader() {
  this.totalFonts = 0;
  this.loadedFonts = 0;
}
/**
 * See {@link FontLoader#load}.
 */
EjectaFontLoader.prototype.load = function(fontFamilies) {
  for (var family in fontFamilies) {
    if (fontFamilies.hasOwnProperty(family)) {
      var fontPath = fontFamilies[family].truetype;
      if (fontPath) {
        window.ejecta.loadFont(fontPath);
      }
    }
  }
};
/**
 * See {@link FontLoader#allLoaded}.
 */
EjectaFontLoader.prototype.allLoaded = function() {
  return true;
};

if (platform.isEjecta()) {
  module.exports = EjectaFontLoader;
} else {
  module.exports = FontLoader;
}