var scrnHt = 120;
var scrnWd = 192;

function buildScreens(ht, wd){

  var screen = new Array();
  console.log("init screen:", screen);

  for(let i = 0; i < ht; i++){

    screen.push(new Array());
    console.log("update screen:", screen);
    console.log("new empty array in screen:", screen[i]);

    for(let j = 0; j < wd; i++){

      screen[i].push[j];

    }
  }
}

window.onload = buildScreens(scrnHt, scrnWd);