function is_SwapImages(navObj,sOnOrOff) {
  document.images[navObj].src = eval("src_" + navObj + "_" + sOnOrOff + ".src");
}

function is_PreloadMainNavImages() {
  src_nav_main_auto_off = new Image();
  src_nav_main_auto_off.src = 'graphics/nav_main_auto_off.gif';
  src_nav_main_auto_on = new Image();
  src_nav_main_auto_on.src = 'graphics/nav_main_auto_on.gif';
  
  src_nav_main_home_off = new Image();
  src_nav_main_home_off.src = 'graphics/nav_main_home_off.gif';
  src_nav_main_home_on = new Image();
  src_nav_main_home_on.src = 'graphics/nav_main_home_on.gif';

  src_nav_main_life_off = new Image();
  src_nav_main_life_off.src = 'graphics/nav_main_life_off.gif';
  src_nav_main_life_on = new Image();
  src_nav_main_life_on.src = 'graphics/nav_main_life_on.gif';

  src_nav_main_health_off = new Image();
  src_nav_main_health_off.src = 'graphics/nav_main_health_off.gif';
  src_nav_main_health_on = new Image();
  src_nav_main_health_on.src = 'graphics/nav_main_health_on.gif';

  src_nav_main_business_off = new Image();
  src_nav_main_business_off.src = 'graphics/nav_main_business_off.gif';
  src_nav_main_business_on = new Image();
  src_nav_main_business_on.src = 'graphics/nav_main_business_on.gif';

  src_nav_main_resources_off = new Image();
  src_nav_main_resources_off.src = 'graphics/nav_main_resources_off.gif';
  src_nav_main_resources_on = new Image();
  src_nav_main_resources_on.src = 'graphics/nav_main_resources_on.gif';

  src_nav_main_contact_off = new Image();
  src_nav_main_contact_off.src = 'graphics/nav_main_contact_off.gif';
  src_nav_main_contact_on = new Image();
  src_nav_main_contact_on.src = 'graphics/nav_main_contact_on.gif';
}

function is_PreloadAutoNavImages() {
  src_nav_auto_coverage_types_off = new Image();
  src_nav_auto_coverage_types_off.src = 'graphics/nav_auto_coverage_types_off.gif';
  src_nav_auto_coverage_types_on = new Image();
  src_nav_auto_coverage_types_on.src = 'graphics/nav_auto_coverage_types_on.gif';
  
  src_nav_auto_cost_factors_off = new Image();
  src_nav_auto_cost_factors_off.src = 'graphics/nav_auto_cost_factors_off.gif';
  src_nav_auto_cost_factors_on = new Image();
  src_nav_auto_cost_factors_on.src = 'graphics/nav_auto_cost_factors_on.gif';
  
  src_nav_auto_bad_drivers_off = new Image();
  src_nav_auto_bad_drivers_off.src = 'graphics/nav_auto_bad_drivers_off.gif';
  src_nav_auto_bad_drivers_on = new Image();
  src_nav_auto_bad_drivers_on.src = 'graphics/nav_auto_bad_drivers_on.gif';
  
  src_nav_auto_discounts_off = new Image();
  src_nav_auto_discounts_off.src = 'graphics/nav_auto_discounts_off.gif';
  src_nav_auto_discounts_on = new Image();
  src_nav_auto_discounts_on.src = 'graphics/nav_auto_discounts_on.gif';
}

function is_PreloadHomeNavImages() {
  src_nav_home_coverages_off = new Image();
  src_nav_home_coverages_off.src = 'graphics/nav_home_coverages_off.gif';
  src_nav_home_coverages_on = new Image();
  src_nav_home_coverages_on.src = 'graphics/nav_home_coverages_on.gif';
    
  src_nav_home_insurance_costs_off = new Image();
  src_nav_home_insurance_costs_off.src = 'graphics/nav_home_insurance_costs_off.gif';
  src_nav_home_insurance_costs_on = new Image();
  src_nav_home_insurance_costs_on.src = 'graphics/nav_home_insurance_costs_on.gif';
    
  src_nav_home_policy_types_off = new Image();
  src_nav_home_policy_types_off.src = 'graphics/nav_home_policy_types_off.gif';
  src_nav_home_policy_types_on = new Image();
  src_nav_home_policy_types_on.src = 'graphics/nav_home_policy_types_on.gif';
}

function is_PreloadHealthNavImages() {
  src_nav_health_coverages_off = new Image();
  src_nav_health_coverages_off.src = 'graphics/nav_health_coverages_off.gif';
  src_nav_health_coverages_on = new Image();
  src_nav_health_coverages_on.src = 'graphics/nav_health_coverages_on.gif';
    
  src_nav_health_business_off = new Image();
  src_nav_health_business_off.src = 'graphics/nav_health_business_off.gif';
  src_nav_health_business_on = new Image();
  src_nav_health_business_on.src = 'graphics/nav_health_business_on.gif';
    
  src_nav_health_group_vs_ind_off = new Image();
  src_nav_health_group_vs_ind_off.src = 'graphics/nav_health_group_vs_ind_off.gif';
  src_nav_health_group_vs_ind_on = new Image();
  src_nav_health_group_vs_ind_on.src = 'graphics/nav_health_group_vs_ind_on.gif';
}

function is_PreloadBusNavImages() {
  src_nav_bus_health_off = new Image();
  src_nav_bus_health_off.src = 'graphics/nav_bus_health_off.gif';
  src_nav_bus_health_on = new Image();
  src_nav_bus_health_on.src = 'graphics/nav_bus_health_on.gif';
    
  src_nav_bus_liability_off = new Image();
  src_nav_bus_liability_off.src = 'graphics/nav_bus_liability_off.gif';
  src_nav_bus_liability_on = new Image();
  src_nav_bus_liability_on.src = 'graphics/nav_bus_liability_on.gif';
    
  src_nav_bus_life_insurance_off = new Image();
  src_nav_bus_life_insurance_off.src = 'graphics/nav_bus_life_insurance_off.gif';
  src_nav_bus_life_insurance_on = new Image();
  src_nav_bus_life_insurance_on.src = 'graphics/nav_bus_life_insurance_on.gif';

  src_nav_bus_owners_policy_off = new Image();
  src_nav_bus_owners_policy_off.src = 'graphics/nav_bus_owners_policy_off.gif';
  src_nav_bus_owners_policy_on = new Image();
  src_nav_bus_owners_policy_on.src = 'graphics/nav_bus_owners_policy_on.gif';
  
  src_nav_bus_workmanscomp_off = new Image();
  src_nav_bus_workmanscomp_off.src = 'graphics/nav_bus_workmanscomp_off.gif';
  src_nav_bus_workmanscomp_on = new Image();
  src_nav_bus_workmanscomp_on.src = 'graphics/nav_bus_workmanscomp_on.gif';
}

function is_HoverMainNavImage(navName) {
  is_SwapImages('nav_main_auto','off');
  is_SwapImages('nav_main_home','off');
  is_SwapImages('nav_main_life','off');
  is_SwapImages('nav_main_health','off');
  is_SwapImages('nav_main_business','off');
  is_SwapImages('nav_main_resources','off');
  is_SwapImages('nav_main_contact','off');
  
  if (navName != '') { is_SwapImages('nav_main_' + navName,'on'); }
}

function is_HoverAutoNavImage(navName) {
  is_SwapImages('nav_auto_coverage_types','off');
  is_SwapImages('nav_auto_cost_factors','off');
  is_SwapImages('nav_auto_bad_drivers','off');
  is_SwapImages('nav_auto_discounts','off');
  
  if (navName != '') { is_SwapImages('nav_auto_' + navName,'on'); }
}

function is_HoverHomeNavImage(navName) {
  is_SwapImages('nav_home_coverages','off');
  is_SwapImages('nav_home_insurance_costs','off');
  is_SwapImages('nav_home_policy_types','off');
  
  if (navName != '') { is_SwapImages('nav_home_' + navName,'on'); }
}

function is_HoverHealthNavImage(navName) {
  is_SwapImages('nav_health_coverages','off');
  is_SwapImages('nav_health_business','off');
  is_SwapImages('nav_health_group_vs_ind','off');
  
  if (navName != '') { is_SwapImages('nav_health_' + navName,'on'); }
}

function is_HoverBusNavImage(navName) {
  is_SwapImages('nav_bus_health','off');
  is_SwapImages('nav_bus_liability','off');
  is_SwapImages('nav_bus_life_insurance','off');
  is_SwapImages('nav_bus_owners_policy','off');
  is_SwapImages('nav_bus_workmanscomp','off');
  
  if (navName != '') { is_SwapImages('nav_bus_' + navName,'on'); }
}

function is_PreloadAllImages() {
  is_PreloadMainNavImages();
  is_PreloadAutoNavImages();
  is_PreloadHomeNavImages();
  is_PreloadHealthNavImages();
  is_PreloadBusNavImages();
}