populateGlobalScope() {
    var scope = this.global.scope;

    // colors
    Object.keys(colors).forEach(function (name) {
      var color = colors[name]
        , rgba = new nodes.RGBA(color[0], color[1], color[2], color[3])
        , node = new nodes.Ident(name, rgba);
      rgba.name = name;
      scope.add(node);
    });

    // expose url function
    scope.add(new nodes.Ident(
      'embedurl',
      new nodes.Function('embedurl', require('../functions/url')({
        limit: false
      }))
    ));

    // user-defined globals
    var globals = this.globals;
    Object.keys(globals).forEach(function (name) {
      var val = globals[name];
      if (!val.nodeName) val = new nodes.Literal(val);
      scope.add(new nodes.Ident(name, val));
    });
  }
Populate the global scope with:

  - css colors
  - user-defined globals

@api private