Scripts DHTML - De la neige qui tombe en arrière-plan.

De la neige qui tombe en arrière-plan. IE4+ et NS4

Suite de la série des scripts inutiles, des flocons qui tombent en arrière-plan de la page.

Démo : en cours.

Etape 1 : Ajouter dans le <BODY> :

<SCRIPT LANGUAGE="Javascript1.2">  var no = 15; // nombre de flocons var speed = 5; // plus le nombre est petit, plus la vitesse augmente var snowflake = "snow.gif"; // image ////////////////////////////////////////////////////////////////////////////// var ns4up = (document.layers) ? 1 : 0; // browser sniffer var ie4up = (document.all) ? 1 : 0; var dx, xp, yp; // coordinate and position variables var am, stx, sty; // amplitude and step variables var i, doc_width = 800, doc_height = 600; if (ns4up) { doc_width = self.innerWidth; doc_height = self.innerHeight; } else if (ie4up) { doc_width = document.body.clientWidth; doc_height = document.body.clientHeight; } dx = new Array(); xp = new Array(); yp = new Array(); am = new Array(); stx = new Array(); sty = new Array(); for (i = 0; i < no; ++ i) { dx[i] = 0; // set coordinate variables xp[i] = Math.random()*(doc_width-50); // set position variables yp[i] = Math.random()*doc_height; am[i] = Math.random()*20; // set amplitude variables stx[i] = 0.02 + Math.random()/10; // set step variables sty[i] = 0.7 + Math.random(); // set step variables if (ns4up) { // set layers if (i == 0) { document.write("<layer name=\"dot"+ i +"\" left=\"15\" "); document.write("top=\"15\" visibility=\"show\"><img src=\""); document.write(snowflake + "\" border=\"0\"></layer>"); } else { document.write("<layer name=\"dot"+ i +"\" left=\"15\" "); document.write("top=\"15\" visibility=\"show\"><img src=\""); document.write(snowflake + "\" border=\"0\"></layer>"); } } else if (ie4up) { if (i == 0) { document.write("<div id=\"dot"+ i +"\" style=\"POSITION: "); document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: "); document.write("visible; TOP: 15px; LEFT: 15px;\"><img src=\""); document.write(snowflake + "\" border=\"0\"></div>"); } else { document.write("<div id=\"dot"+ i +"\" style=\"POSITION: "); document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: "); document.write("visible; TOP: 15px; LEFT: 15px;\"><img src=\""); document.write(snowflake + "\" border=\"0\"></div>"); } } } function snowNS() { // Netscape main animation function for (i = 0; i < no; ++ i) { // iterate for every dot yp[i] += sty[i]; if (yp[i] > doc_height-50) { xp[i] = Math.random()*(doc_width-am[i]-30); yp[i] = 0; stx[i] = 0.02 + Math.random()/10; sty[i] = 0.7 + Math.random(); doc_width = self.innerWidth; doc_height = self.innerHeight; } dx[i] += stx[i]; document.layers["dot"+i].top = yp[i]; document.layers["dot"+i].left = xp[i] + am[i]*Math.sin(dx[i]); } setTimeout("snowNS()", speed); } function snowIE() { // IE main animation function for (i = 0; i < no; ++ i) { // iterate for every dot yp[i] += sty[i]; if (yp[i] > doc_height-50) { xp[i] = Math.random()*(doc_width-am[i]-30); yp[i] = 0; stx[i] = 0.02 + Math.random()/10; sty[i] = 0.7 + Math.random(); doc_width = document.body.clientWidth; doc_height = document.body.clientHeight; } dx[i] += stx[i]; document.all["dot"+i].style.pixelTop = yp[i]; document.all["dot"+i].style.pixelLeft = xp[i] + am[i]*Math.sin(dx[i]); } setTimeout("snowIE()", speed); } if (ns4up) { snowNS(); } else if (ie4up) { snowIE(); } // End --> </script>

On peut modifier quelques paramètres au début du script :
var no = 15; // nombre de flocons
var speed = 5; // plus le nombre est petit, plus la vitesse augmente
var snowflake = "snow.gif"; // image

Etape 2 :
Capturer l'image (bouton droit >> enregistrer l'image sous) que vous placerez dans le répertoire de votre site.