var gLogoImgTag = null;	// tag img s logem
var gLogoCount = 0;		// pocet obrazku v rotatoru
var gLogoCache = new Array();	// nacacheovane obrazky
var gLogoNames = new Array();	// nacacheovane titulky
var gLogoIdx = 0;
var log;

function preloadLogoImages( list)
{
	
	gLogoImgTag = gE( "logoImg");
	
	
	log = gE( 'log');

	// pokud se nam ho nepodari ziskat,
	// tak cely rotator postrada smysl
	if( !gLogoImgTag)
		return;
		
	gLogoCount = list.length;
	
	for( i=0; i<gLogoCount; i++)
	{
		gLogoCache[ i] = new Image();
		gLogoCache[ i].src = list[ i][ 1];
		gLogoCache[ i].width = list[ i][ 2];
		gLogoCache[ i].height = list[ i][ 3];
		gLogoCache[ i].pTop = (100-list[ i][ 3])/2;
		
		gLogoNames[ i] = list[ i][ 0];
		
	} // for(...)
	
} // function preloadLogoImages()


function runLogoSwitch( sec)
{
	// pokdu nemame handler tagu IMG,
	// neni treba rotator spoustet
	if( !gLogoImgTag)
		return;

	// zaciname od nuly
	gLogoIdx = 0;
		
	// deme na to
	setTimeout( "logoSwitchCallback(" + sec + ")", sec*1000);
}


function logoSwitchCallback( sec)
{
	// zobrazime dalsi logo
	
	// zvys index obrazky (pozor na preteceni!)
	gLogoIdx = ((gLogoIdx+1)>=gLogoCount) ? 0 : gLogoIdx+1;
	
	// zobrazime obrazek
	gLogoImgTag.src = gLogoCache[ gLogoIdx].src;
	gLogoImgTag.width = gLogoCache[ gLogoIdx].width;
	gLogoImgTag.height = gLogoCache[ gLogoIdx].height;
	
	gLogoImgTag.style.paddingTop = gLogoCache[ gLogoIdx].pTop + 'px';
	
	// ...a k nemu jeste alternativni text
	gLogoImgTag.alt = gLogoNames[ gLogoIdx];
	
	// self call
	setTimeout( "logoSwitchCallback(" + sec + ")", sec*1000);
}