#equirectangular-projection
project coordinates into pixel for equirectagular map
npm install equirectangular-projection
//@arguments (Lng <Number>, Lat <Number>, viewPortWidth <Number>
//@return {top: <Number>, left: <Number>}
var project = require('equirectangular-projection').project;
var position = project(145.5664, 30.345, 300);
console.log(position);
// => { top: 135.65266666666668, left: 200.575 }