// cross navigator functions

var isDOM = (document.getElementById ? true : false); 
var isIE4 = ((document.all && !isDOM) ? true : false);
var isNS4 = (document.layers ? true : false);
var isDyn = (isDOM || isIE4 || isNS4);

function getTag(id){
 if (isDOM) return document.getElementById(id);
 if (isIE4) return document.all[id];
 if (isNS4) return document.layers[id];
}

function getTagStyle(id){
 return (isNS4 ? getTag(id) : getTag(id).style);
}

//*************************************************************	
// pour allumer
//*************************************************************

  function allumer(e, value) {
        $(e).css('opacity',value);
  }
 


//*************************************************************	
// pour précharger les images "artworks"
//*************************************************************

i1 = new Image;
i1.src = "pix/artworks/artwork01.jpg";
i2 = new Image;
i2.src = "pix/artworks/conchiglie.jpg";
i3 = new Image;
i3.src = "pix/artworks/coral-field.jpg";
i4 = new Image;
i4.src = "pix/artworks/corralium.jpg";
i5 = new Image;
i5.src = "pix/artworks/dog-canyon.jpg";
i6 = new Image;
i6.src = "pix/artworks/etna.jpg";
i7 = new Image;
i7.src = "pix/artworks/formica-leo.jpg";
i8 = new Image;
i8.src = "pix/artworks/lapis-scarabeo.jpg";
i9 = new Image;
i9.src = "pix/artworks/lapis-tartaruga.jpg";
i10 = new Image;
i10.src = "pix/artworks/mineralia.jpg";
i11 = new Image;
i11.src = "pix/artworks/natura-viva.jpg";
i12 = new Image;
i12.src = "pix/artworks/pantalica.jpg";
i13 = new Image;
i13.src = "pix/artworks/penombra.jpg";
i14 = new Image;
i14.src = "pix/artworks/promised-land.jpg";
i15 = new Image;
i15.src = "pix/artworks/selva.jpg";
i16 = new Image;
i16.src = "pix/artworks/siracusa.jpg";
i17 = new Image;
i17.src = "pix/artworks/terra01.jpg";
i18 = new Image;
i18.src = "pix/artworks/terra02.jpg";
i19 = new Image;
i19.src = "pix/artworks/the-wave.jpg";
i20 = new Image;
i20.src = "pix/artworks/vincent.jpg";