source: extensions/Flash_Gallery/modules/prometeus/js/prometeus.js @ 3599

// ==================================================
// script realized by Gérard Ferrandez - June 2006
// http://www.dhteumeuleu.com
// ==================================================

id = function(o) { return document.getElementById(o); }
px = function (x) {     return ''.concat(Math.round(x), 'px'); }

//////////////////////////////////////////////////////////////////////////////
function resize() {     gf.resize(); }
onresize = resize;

document.onmousemove = function(e)
{
        if(window.event) e=window.event;
        gf.xm = (e.x || e.clientX) - gf.nx - gf.nw * .5;
        gf.ym = (e.y || e.clientY) - gf.ny - gf.nh * .5;
}

//////////////////////////////////////////////////////////////////////////////
var gf = {
        O    : [],
        cont : 0,
        N    : 0,
        S    : 0,
        img  : 0,
        spa  : 0,
        xm   : 0,
        ym   : 0,
        nx   : 0,
        ny   : 0,
        nw   : 0,
        nh   : 0,
        cx   : 0,
        cy   : 0,
        zoom : 1,
        x    : 0,
        y    : 0,
        z    : -40000,
        xt   : 0,
        yt   : 0,
        zt   : 0,
//////////////////////////////////////////////////////////////////////////////
        resize : function ()
        {
                var o   = id('canvas');
                gf.nx   = o.offsetLeft;
                gf.ny   = o.offsetTop;
                gf.nw   = o.offsetWidth;
                gf.nh   = o.offsetHeight;
                gf.zoom = gf.nh / 700;
        },

        CObj : function (n)
        {
                this.n                = n;
                this.x                = gf.zoom * Math.random() * gf.nw * 2 - gf.nw;
                this.y                = gf.zoom * Math.random() * gf.nh * 2 - gf.nh;
                this.z                = Math.round(n * (10000 / gf.N));
                this.w                = gf.img[n].width;
                this.h                = gf.img[n].height;
                this.oxt              = gf.spa[n];
                this.oxs              = this.oxt.style;
                this.txt              = gf.spa[n].innerHTML;
                this.oxt.innerHTML    = "";
                this.obj              = gf.img[n];
                this.obs              = this.obj.style;
                this.obj.parent       = this;
                this.obj.onclick      = function() { this.parent.click(); }
                this.obj.ondrag       = function() { return false; }
                this.oxt.style.zIndex = this.obj.style.zIndex = Math.round(1000000 - this.z);
                this.F                = false;
                this.CF               = 100;
                this.sto              = [];

                this.anim = function()
                {
                        var f = 700 + this.z - gf.z;
                        if (f > 0)
                        {
                                var d               = 1000 / f;
                                var X               = gf.nw * .5 + ((this.x - gf.x - gf.cx) * d);
                                var Y               = gf.nh * .5 + ((this.y - gf.y - gf.cy) * d);
                                var W               = d * this.w * gf.zoom;
                                var H               = d * this.h * gf.zoom;
                                this.obs.left       = px(X - W * .5);
                                this.obs.top        = px(Y - H * .5);
                                this.obs.width      = px(W);
                                this.obs.height     = px(H);
                                this.oxs.visibility = (this.CF-- > 0 && Math.random() > .9) ? "hidden" : "visible";
                                this.oxs.left       = px(X - W * .5);
                                this.oxs.top        = px(Y + H * .5);
                                if((gf.zt - gf.z) < 20)
                                {
                                        if(!this.F)
                                        {
                                                this.F            = true;
                                                this.CF           = Math.random() * 200;
                                                this.oxs.fontSize = px(1 + d * 20 * gf.zoom);
                                                var T             = "";
                                                var tn            = this.txt.length;
                                                for(var i = 0; i < tn; i++)
                                                {
                                                        T = T.concat(this.txt.charAt(i));
                                                        this.sto[i] = setTimeout('gf.O['.concat(n, '].oxt.innerHTML = "', T.concat(" "), '";'), Math.round(f / 4) + 32 * i);
                                                }
                                        }
                                }
                                else
                                {
                                        this.F = false;
                                        this.oxt.innerHTML = "";
                                }
                        }
                        else
                        {
                                this.x  = gf.zoom * Math.random() * gf.nw * 2 - gf.nw;
                                this.y  = gf.zoom * Math.random() * gf.nh * 2 - gf.nh;
                                this.z += 10000;
                                this.oxs.zIndex = this.obs.zIndex = Math.round(1000000 - this.z);
                        }
                }

                this.cto = function()
                {
                        var i = this.txt.length;
                        while (i--) clearTimeout(this.sto[i]);
                }

                this.click = function()
                {
                        var i = gf.N;
                        while (i--) gf.O[i].cto();
                        if(gf.S != this)
                        {
                                gf.xt = this.x;
                                gf.yt = this.y;
                                gf.zt = this.z;
                                gf.S  = this;
                        }
                        else
                        {
                                gf.S   = 0;
                                gf.zt += 1600;
                        }
                }
        },

        init : function ()
        {
                gf.cx   = gf.nw / 2;
                gf.cy   = gf.nh / 2;
                gf.cont = id("canvas");
                gf.img  = id("canvas").getElementsByTagName("img");
                gf.spa  = id("canvas").getElementsByTagName("span");
                gf.N    = gf.img.length;
                for (var i = 0; i < gf.N; i++) gf.O[i] = new gf.CObj(i);
                gf.run();
                gf.O[0].click();
        },

        run : function ()
        {
                gf.cx += (gf.xm - gf.cx) * .1;
                gf.cy += (gf.ym - gf.cy) * .1;
                gf.x  += (gf.xt - gf.x)  * .05;
                gf.y  += (gf.yt - gf.y)  * .05;
                gf.z  += (gf.zt - gf.z)  * .05;
                var i = gf.N;
                while (i--) gf.O[i].anim();
                setTimeout(gf.run, 16);
        }
}

onload = function() {
        resize();
        gf.init();
}