JS相册图片抖动放大展示效果的示例代码

上篇文章给大家介绍了JS实现简单抖动效果，感兴趣的朋友点击查看。

今天给大家分享JS相册图片抖动放大展示效果，效果图如下所示：

var xm;
var ym;

/* ==== onmousemove event ==== */
document.onmousemove = function(e){
	if(window.event) e=window.event;
	xm = (e.x || e.clientX);
	ym = (e.y || e.clientY);
}

/* ==== window resize ==== */
function resize() {
	if(diapo)diapo.resize();
}
onresize = resize;

/* ==== opacity ==== */
setOpacity = function(o, alpha){
	if(o.filters)o.filters.alpha.opacity = alpha * 100; else o.style.opacity = alpha;
}

/* ===== encapsulate script ==== */
diapo = {
	O : [],
	DC : 0,
	img : 0,
	txt : 0,
	N : 0,
	xm : 0,
	ym : 0,
	nx : 0,
	ny : 0,
	nw : 0,
	nh : 0,
	rs : 0,
	rsB : 0,
	zo : 0,
	tx_pos : 0,
	tx_var : 0,
	tx_target : 0,

	/// script parameters
	attraction : 2,
	acceleration : .9,
	dampening : .1,
	zoomOver : 2,
	zoomClick : 6,
	transparency : .8,
	font_size: 18,
	//

	/* ==== diapo resize ==== */
	resize : function(){
		with(this){
			nx = DC.offsetLeft;
			ny = DC.offsetTop;
			nw = DC.offsetWidth;
			nh = DC.offsetHeight;
			txt.style.fontSize = Math.round(nh / font_size) + "px";
			if(Math.abs(rs-rsB)<100) for(var i=0; i<N; i++) O[i].resize();
			rsB = rs;
		}
	},

	/* ==== create diapo ==== */
	CDiapo : function(o){
		/* ==== init variables ==== */
		this.o    = o;
		this.x_pos  = this.y_pos  = 0;
		this.x_origin = this.y_origin = 0;
		this.x_var  = this.y_var  = 0;
		this.x_target = this.y_target = 0;
		this.w_pos  = this.h_pos  = 0;
		this.w_origin = this.h_origin = 0;
		this.w_var  = this.h_var  = 0;
		this.w_target = this.h_target = 0;
		this.over   = false;
		this.click  = false;

		/* ==== create shadow ==== */
		this.spa = document.createElement("span");
		this.spa.className = "spaDC";
		diapo.DC.appendChild(this.spa);

		/* ==== create thumbnail image ==== */
		this.img = document.createElement("img");
		this.img.className = "imgDC";
		this.img.src = o.src;
		this.img.O = this;
		diapo.DC.appendChild(this.img);
		setOpacity(this.img, diapo.transparency);

		/* ==== mouse events ==== */
		this.img.onselectstart = new Function("return false;");
		this.img.ondrag = new Function("return false;");
		this.img.onmouseover = function(){
			diapo.tx_target=0;
			diapo.txt.innerHTML=this.O.o.alt;
			this.O.over=true;
			setOpacity(this,this.O.click?diapo.transparency:1);
		}
		this.img.onmouseout = function(){
			diapo.tx_target=-diapo.nw;
			this.O.over=false;
			setOpacity(this,diapo.transparency);
		}
		this.img.onclick = function() {
			if(!this.O.click){
				if(diapo.zo && diapo.zo != this) diapo.zo.onclick();
				this.O.click = true;
				this.O.x_origin = (diapo.nw - (this.O.w_origin * diapo.zoomClick)) / 2;
				this.O.y_origin = (diapo.nh - (this.O.h_origin * diapo.zoomClick)) / 2;
				diapo.zo = this;
				setOpacity(this,diapo.transparency);
			} else {
				this.O.click = false;
				this.O.over = false;
				this.O.resize();
				diapo.zo = 0;
			}
		}

		/* ==== rearrange thumbnails based on "imgsrc" images position ==== */
		this.resize = function (){
			with (this) {
				x_origin = o.offsetLeft;
				y_origin = o.offsetTop;
				w_origin = o.offsetWidth;
				h_origin = o.offsetHeight;
			}
		}

		/* ==== animation function ==== */
		this.position = function (){
			with (this) {
				/* ==== set target position ==== */
				w_target = w_origin;
				h_target = h_origin;
				if(over){
					/* ==== mouse over ==== */
					w_target = w_origin * diapo.zoomOver;
					h_target = h_origin * diapo.zoomOver;
					x_target = diapo.xm - w_pos / 2 - (diapo.xm - (x_origin + w_pos / 2)) / (diapo.attraction*(click?10:1));
					y_target = diapo.ym - h_pos / 2 - (diapo.ym - (y_origin + h_pos / 2)) / (diapo.attraction*(click?10:1));
				} else {
					/* ==== mouse out ==== */
					x_target = x_origin;
					y_target = y_origin;
				}
				if(click){
					/* ==== clicked ==== */
					w_target = w_origin * diapo.zoomClick;
					h_target = h_origin * diapo.zoomClick;
				}

				/* ==== magic spring equations ==== */
				x_pos += x_var = x_var * diapo.acceleration + (x_target - x_pos) * diapo.dampening;
				y_pos += y_var = y_var * diapo.acceleration + (y_target - y_pos) * diapo.dampening;
				w_pos += w_var = w_var * (diapo.acceleration * .5) + (w_target - w_pos) * (diapo.dampening * .5);
				h_pos += h_var = h_var * (diapo.acceleration * .5) + (h_target - h_pos) * (diapo.dampening * .5);
				diapo.rs += (Math.abs(x_var) + Math.abs(y_var));

				/* ==== html animation ==== */
				with(img.style){
					left  = Math.round(x_pos) + "px";
					top  = Math.round(y_pos) + "px";
					width = Math.round(Math.max(0, w_pos)) + "px";
					height = Math.round(Math.max(0, h_pos)) + "px";
					zIndex = Math.round(w_pos);
				}
				with(spa.style){
					left  = Math.round(x_pos + w_pos * .1) + "px";
					top  = Math.round(y_pos + h_pos * .1) + "px";
					width = Math.round(Math.max(0, w_pos * 1.1)) + "px";
					height = Math.round(Math.max(0, h_pos * 1.1)) + "px";
					zIndex = Math.round(w_pos);
				}
			}
		}
	},

	/* ==== main loop ==== */
	run : function(){
		diapo.xm = xm - diapo.nx;
		diapo.ym = ym - diapo.ny;
		/* ==== caption anim ==== */
		diapo.tx_pos += diapo.tx_var = diapo.tx_var * .9 + (diapo.tx_target - diapo.tx_pos) * .02;
		diapo.txt.style.left = Math.round(diapo.tx_pos) + "px";
		/* ==== images anim ==== */
		for(var i in diapo.O) diapo.O[i].position();
		/* ==== loop ==== */
		setTimeout("diapo.run();", 16);
	},

	/* ==== load images ==== */
	images_load : function(){
		// ===== loop until all images are loaded =====
		var M = 0;
		for(var i=0; i<diapo.N; i++) {
			if(diapo.img[i].complete) {
				diapo.img[i].style.position = "relative";
				diapo.O[i].img.style.visibility = "visible";
				diapo.O[i].spa.style.visibility = "visible";
				M++;
			}
			resize();
		}
		if(M<diapo.N) setTimeout("diapo.images_load();", 128);
	},

	/* ==== init script ==== */
	init : function() {
		diapo.DC = document.getElementById("diapoContainer");
		diapo.img = diapo.DC.getElementsByTagName("img");
		diapo.txt = document.getElementById("caption");
		diapo.N = diapo.img.length;
		for(i=0; i<diapo.N; i++) diapo.O.push(new diapo.CDiapo(diapo.img[i]));
		diapo.resize();
		diapo.tx_pos = -diapo.nw;
		diapo.tx_target = -diapo.nw;
		diapo.images_load();
		diapo.run();
	}
}

/* ==== start script ==== */
function dom_onload() {
	if(document.getElementById("diapoContainer")) diapo.init(); else setTimeout("dom_onload();", 128);
}
dom_onload();

到此这篇关于JS相册图片抖动放大展示效果的示例代码的文章就介绍到这了,更多相关js图片放大抖动内容请搜索我们以前的文章或继续浏览下面的相关文章希望大家以后多多支持我们！