// ************************************
// variables for calculator
// ************************************

var displayval = "0";	// value to be displayed
var lastpress = "eq";	// need to keep track of last button pressed, start off at beginning of sequence
var calcstr = "";	// expression to be calculated
var memoryval = 0;

// ************************************
// menu functions
// ************************************

function initialise() {
  if (document.all) {					//Internet Explorer
    theSubHead   = phead.style
    theSubHead   = shead.style
    thePlainMenu = menu0.style
    showit = 'visible'
    hideit = 'hidden'
  }

  if (document.layers) {				// Netscape 4
    thePageHead  = document.layers['phead']
    theSubHead   = document.layers['shead']
    thePlainMenu = document.layers['menu0']
    showit = 'visible'
    hideit = 'hidden'
  }

  if (!document.all && document.getElementById) {	// Netscape 6+
    theSubHead   = document.getElementById('phead').style
    theSubHead   = document.getElementById('shead').style
    thePlainMenu = document.getElementById('menu0').style
    showit = 'visible'
    hideit = 'hidden'
  }
  hidemenu();

  document.onmousedown=disablerclick
}

function disablerclick() {
  if (event.button==2) {
    alert("This image is copyright - right click is disabled");
    return false;
  }
}

function hidemenu() {
//  theLayer2.visibility = hideit;
}

  function showmenu(submenu) {
    hidemenu();
//    switch(submenu) {
//      case 2:
//          theLayer2.visibility = showit;
//        break;
//      case 3:
//          theLayer3.visibility = showit;
//        break;
//    }
  }

  function showclickable(imglink,imgnam) {
    eval ("document.images["+imglink+"].src = 'buttons/" + imgnam + "_click.gif'");
  }

  function shownormal(imglink,imgnam) {
    eval ("document.images["+imglink+"].src = 'buttons/" + imgnam + ".gif'");
  }