[Script] JavaScript Bild funktionen

/***************************************************
* verkleinert ein bild
*
* @param (int) maxWidth 
* @param (int) maxHEight
*/ 
Image.prototype.resize = function(maxWidth, maxHeight) {
 if(this.src == '') return false;
 else if(this.width > maxWidth || this.height > maxHeight) {
 var posWidth = maxWidth / this.width;
 var posHeight = maxHeight / this.heigth;
 if(posWidth > posHeight) {
 this.width = Math.round(this.width * posHeight);
 this.height = maxHeight; 
 } else {
 this.width = maxWidth;
 this.height = Math.round(this.height * posWidth);
 }
 }
}

/***************************************************
* bild(er) anhand von namen verkleindern
*
* @param (string) name
* @param (int) maxWidth
* @param (int) maxHeight
*/
Image.prototype.resizeByName = function(name, maxWidth, maxHeight) {
 this.findByName(name);
 for(i in this.doc) {
 this.src = this.doc[i].src;
 var wh = new Array(this.width, this.height);
 this.resize(maxWidth, maxHeight);
 this.doc[i].width = this.width;
 this.doc[i].height = this.height;
 if(wh[0] != this.width || wh[1] != this.height) { //verkleinert
 if(!img.isLinked(this.doc[i])) {
 var a = document.createElement('a');
 a.href = this.src;
 a.target = 'blank';
 a.appendChild(this.doc[i].cloneNode(true));
 a.title = 'Klicken für volle Größe';
 this.doc[i].parentNode.replaceChild(a, this.doc[i]);
 }
 }
 }
}

/***************************************************
* bild(er) anhand von namen im document suchen
*
* @param (string) name
* @return (array) imgs
*/
Image.prototype.findByName = function(name) {
 var doc = document.getElementsByTagName('img');
 var imgs = new Array();
 for(i in doc) {
 if(doc[i].name == name) imgs.push(doc[i]);
 }
 this.doc = imgs;
 return imgs;
}

/***************************************************
* bild anhand von src im document suchen
*
* @param (bool) once (nur ein element speichern)
* @return (object) node (erstes gefundenes bild)
*/
Image.prototype.find = function(once) {
 if(typeof this.src == 'undefined' || this.src == '') return false;
 var tags = document.getElementsByTagName('img');
 var imgs = new Array();
 for(i in tags) {
 if(tags[i].src == this.src) {
 imgs.push(tags[i]);
 }
 }
 this.doc = ((once) ? imgs : imgs[0]);
 this.contextNode = imgs[0];
 return this.contextNode;
}

/***************************************************
* prüfen ob ein bild verlinkt wurde
*
* @return (bool)
*/
Image.prototype.isLinked = function(img) {
 if(img.nodeName.toUpperCase() != 'IMG') return false;
 var current = img;
 do {
 current = current.parentNode;
 if(current.nodeName == 'A') return true;
 } while(current.nodeName != 'DIV' && current.nodeName != 'BODY');
 return false;
}