实现效果：
第一种: 使用tagcanvas
tagcanvas.js源码：
/**
* Copyright (C) 2010-2012 Graham Breach
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see
*/
(function(){
var i, j, abs = Math.abs, sin = Math.sin, cos = Math.cos, max = Math.max, min = Math.min,
hexlookup3 = {}, hexlookup2 = {}, hexlookup1 = {
0:"0,", 1:"17,", 2:"34,", 3:"51,", 4:"68,", 5:"85,",
6:"102,", 7:"119,", 8:"136,", 9:"153,", a:"170,", A:"170,",
b:"187,", B:"187,", c:"204,", C:"204,", d:"221,", D:"221,",
e:"238,", E:"238,", f:"255,", F:"255,"
}, Oproto, Tproto, TCproto, doc = document, ocanvas;
for(i = 0; i < 256; ++i) {
j = i.toString(16);
if(i < 16)
j = '0' + j;
hexlookup2[j] = hexlookup2[j.toUpperCase()] = i.toString() + ',';
}
function Defined(d) {
return typeof(d) != 'undefined';
}
function PointsOnSphere(n) {
var i, y, r, phi, pts = [], inc = Math.PI * (3-Math.sqrt(5)), off = 2/n;
for(i = 0; i < n; ++i) {
y = i * off - 1 + (off / 2);
r = Math.sqrt(1 - y*y);
phi = i * inc;
pts.push([cos(phi)*r, y, sin(phi)*r]);
}
return pts;
}
function Cylinder(n,o,i,j,k,l) {
var phi, pts = [], inc = Math.PI * (3-Math.sqrt(5)), off = 2/n;
for(i = 0; i < n; ++i) {
j = i * off - 1 + (off / 2);
phi = i * inc;
k = cos(phi);
l = sin(phi);
pts.push(o ? [j, k, l] : [k, j, l]);
}
return pts;
}
function PointsOnCylinderV(n) { return Cylinder(n) }
function PointsOnCylinderH(n) { return Cylinder(n,1) }
function SetAlpha(c,a) {
var d = c, p1, p2, ae = (a*1).toPrecision(3) + ')';
if(c[0] === '#') {
if(!hexlookup3[c])
if(c.length === 4)
hexlookup3[c] = 'rgba(' + hexlookup1[c[1]] + hexlookup1[c[2]] + hexlookup1[c[3]];
else
hexlookup3[c] = 'rgba(' + hexlookup2[c.substr(1,2)] + hexlookup2[c.substr(3,2)] + hexlookup2[c.substr(5,2)];
d = hexlookup3[c] + ae;
} else if(c.substr(0,4) === 'rgb(' || c.substr(0,4) === 'hsl(') {
d = (c.replace('(','a(').replace(')', ',' + ae));
} else if(c.substr(0,5) === 'rgba(' || c.substr(0,5) === 'hsla(') {
p1 = c.lastIndexOf(',') + 1, p2 = c.indexOf(')');
a *= parseFloat(c.substring(p1,p2));
d = c.substr(0,p1) + a.toPrecision(3) + ')';
}
return d;
}
function NewCanvas(w,h) {
// if using excanvas, give up now
if(window.G_vmlCanvasManager)
return null;
var c = doc.createElement('canvas');
c.width = w;
c.height = h;
return c;
}
// I think all browsers pass this test now...
function ShadowAlphaBroken() {
var cv = NewCanvas(3,3), c, i;
if(!cv)
return false;
c = cv.getContext('2d');
c.strokeStyle = '#000';
c.shadowColor = '#fff';
c.shadowBlur = 3;
c.globalAlpha = 0;
c.strokeRect(2,2,2,2);
c.globalAlpha = 1;
i = c.getImageData(2,2,1,1);
cv = null;
return (i.data[0] > 0);
}
function FindGradientColour(t,p) {
var l = 1024, g = t.weightGradient, cv, c, i, gd, d;
if(t.gCanvas) {
c = t.gCanvas.getContext('2d');
} else {
t.gCanvas = cv = NewCanvas(l,1);
if(!cv)
return null;
c = cv.getContext('2d');
gd = c.createLinearGradient(0,0,l,0);
for(i in g)
gd.addColorStop(1-i, g[i]);
c.fillStyle = gd;
c.fillRect(0,0,l,1);
}
d = c.getImageData(~~((l-1)*p),0,1,1).data;
return 'rgba(' + d[0] + ',' + d[1] + ',' + d[2] + ',' + (d[3]/255) + ')';
}
function TextSet(c,f,l,s,sc,sb,so) {
var xo = (sb || 0) + (so && so[0] < 0 ? abs(so[0]) : 0),
yo = (sb || 0) + (so && so[1] < 0 ? abs(so[1]) : 0);
c.font = f;
c.textBaseline = 'top';
c.fillStyle = l;
sc && (c.shadowColor = sc);
sb && (c.shadowBlur = sb);
so && (c.shadowOffsetX = so[0], c.shadowOffsetY = so[1]);
c.fillText(s, xo, yo);
}
function TextToCanvas(s,f,ht,w,h,l,sc,sb,so,padx,pady) {
var cw = w + abs(so[0]) + sb + sb, ch = h + abs(so[1]) + sb + sb, cv, c;
cv = NewCanvas(cw+padx,ch+pady);
if(!cv)
return null;
c = cv.getContext('2d');
TextSet(c,f,l,s,sc,sb,so);
return cv;
}
function AddShadowToImage(i,sc,sb,so) {
var cw = i.width + abs(so[0]) + sb + sb, ch = i.height + abs(so[1]) + sb + sb, cv, c,
xo = (sb || 0) + (so && so[0] < 0 ? abs(so[0]) : 0),
yo = (sb || 0) + (so && so[1] < 0 ? abs(so[1]) : 0);
cv = NewCanvas(cw,ch);
if(!cv)
return null;
c = cv.getContext('2d');
sc && (c.shadowColor = sc);
sb && (c.shadowBlur = sb);
so && (c.shadowOffsetX = so[0], c.shadowOffsetY = so[1]);
c.drawImage(i, xo, yo);
return cv;
}
function FindTextBoundingBox(s,f,ht) {
var w = parseInt(s.length * ht), h = parseInt(ht * 2), cv = NewCanvas(w,h), c, idata, w1, h1, x, y, i, ex;
if(!cv)
return null;
c = cv.getContext('2d');
c.fillStyle = '#000';
c.fillRect(0,0,w,h);
TextSet(c,ht + 'px ' + f,'#fff',s)
idata = c.getImageData(0,0,w,h);
w1 = idata.width; h1 = idata.height;
ex = {
min: { x: w1, y: h1 },
max: { x: -1, y: -1 }
};
for(y = 0; y < h1; ++y) {
for(x = 0; x < w1; ++x) {
i = (y * w1 + x) * 4;
if(idata.data[i+1] > 0) {
if(x < ex.min.x) ex.min.x = x;
if(x > ex.max.x) ex.max.x = x;
if(y < ex.min.y) ex.min.y = y;
if(y > ex.max.y) ex.max.y = y;
}
}
}
// device pixels might not be css pixels
if(w1 != w) {
ex.min.x *= (w / w1);
ex.max.x *= (w / w1);
}
if(h1 != h) {
ex.min.y *= (w / h1);
ex.max.y *= (w / h1);
}
cv = null;
return ex;
}
function FixFont(f) {
return "'" + f.replace(/(\'|\")/g,'').replace(/\s*,\s*/g, "', '") + "'";
}
function AddHandler(h,f,e) {
e = e || doc;
if(e.addEventListener)
e.addEventListener(h,f,false);
else
e.attachEvent('on' + h, f);
}
function AddImage(i,t,tl) {
if(i.complete) {
t.w = i.width;
t.h = i.height;
tl.push(t);
} else {
AddHandler('load',function() {
t.w = this.width;
t.h = this.height;
tl.push(t);
},i);
}
}
function GetProperty(e,p) {
var dv = doc.defaultView, pc = p.replace(/\-([a-z])/g,function(a){return a[1].toUpperCase()});
return (dv && dv.getComputedStyle && dv.getComputedStyle(e,null).getPropertyValue(p)) ||
(e.currentStyle && e.currentStyle[pc]);
}
function FindWeight(t,a) {
var w = 1, p;
if(t.weightFrom) {
w = 1 * (a.getAttribute(t.weightFrom) || t.textHeight);
} else if(p = GetProperty(a,'font-size')) {
w = (p.indexOf('px') > -1 && p.replace('px','') * 1) ||
(p.indexOf('pt') > -1 && p.replace('pt','') * 1.25) ||
p * 3.3;
} else {
t.weight = false;
}
return w;
}
function MouseMove(e) {
var i, tc, dd = doc.documentElement, p;
for(i in TagCanvas.tc) {
tc = TagCanvas.tc[i];
if(tc.tttimer) {
clearTimeout(tc.tttimer);
tc.tttimer = null;
}
p = AbsPos(i);
if(e.pageX) {
tc.mx = e.pageX - p.x;
tc.my = e.pageY - p.y;
} else {
tc.mx = e.clientX + (dd.scrollLeft || doc.body.scrollLeft) - p.x;
tc.my = e.clientY + (dd.scrollTop || doc.body.scrollTop) - p.y;
}
}
}
function MouseClick(e) {
var t = TagCanvas, cb = doc.addEventListener ? 0 : 1,
tg = e.target && Defined(e.target.id) ? e.target.id : e.srcElement.parentNode.id;
if(tg && e.button == cb && t.tc[tg]) {
MouseMove(e);
t.tc[tg].Clicked(e);
}
}
function MouseWheel(e) {
var t = TagCanvas,
tg = e.target && Defined(e.target.id) ? e.target.id : e.srcElement.parentNode.id;
if(tg && t.tc[tg]) {
e.cancelBubble = true;
e.returnValue = false;
e.preventDefault && e.preventDefault();
t.tc[tg].Wheel((e.wheelDelta || e.detail) > 0);
}
}
function DrawCanvas() {
var t = TagCanvas.tc, i;
for(i in t)
t[i].Draw();
}
function AbsPos(id) {
var e = doc.getElementById(id), x = e.offsetLeft, y = e.offsetTop;
while(e = e.offsetParent) {
x += e.offsetLeft;
y += e.offsetTop;
}
return {x:x,y:y};
}
function RotX(p1,t) {
var s = sin(t), c = cos(t);
return {x:p1.x, y:(p1.y * c) + (p1.z * s), z:(p1.y * -s) + (p1.z * c)};
}
function RotY(p1,t) {
var s = sin(t), c = cos(t);
return {x:(p1.x * c) + (p1.z * -s), y:p1.y, z:(p1.x * s) + (p1.z * c)};
}
function Project(tc,p1,w,h,fov,asp) {
var yn, xn, zn, m = tc.z1 / (tc.z1 + tc.z2 + p1.z);
yn = p1.y * m;
xn = p1.x * m;
zn = tc.z2 + p1.z;
return {x:xn, y:yn, z:zn};
}
/**
* @constructor
*/
function Outline(tc) {
this.ts = new Date().valueOf();
this.tc = tc;
this.x = this.y = this.w = this.h = this.sc = 1;
this.z = 0;
this.Draw = tc.pulsateTo < 1 && tc.outlineMethod != 'colour' ? this.DrawPulsate : this.DrawSimple;
this.SetMethod(tc.outlineMethod);
}
Oproto = Outline.prototype;
Oproto.SetMethod = function(om) {
var methods = {
block: ['PreDraw','DrawBlock'],
colour: ['PreDraw','DrawColour'],
outline: ['PostDraw','DrawOutline'],
classic: ['LastDraw','DrawOutline']
}, funcs = methods[om] || methods.outline;
this[funcs[0]] = this.Draw;
this.drawFunc = this[funcs[1]];
};
Oproto.Update = function(x,y,w,h,sc,p,xo,yo) {
var o = this.tc.outlineOffset, o2 = 2 * o;
this.x = sc * x + xo - o;
this.y = sc * y + yo - o;
this.w = sc * w + o2;
this.h = sc * h + o2;
this.sc = sc; // used to determine frontmost
this.z = p.z;
};
Oproto.DrawOutline = function(c,x,y,w,h,colour) {
c.strokeStyle = colour;
c.strokeRect(x,y,w,h);
};
Oproto.DrawColour = function(c,x,y,w,h,colour,tag,x1,y1) {
return this[tag.image ? 'DrawColourImage' : 'DrawColourText'](c,x,y,w,h,colour,tag,x1,y1);
};
Oproto.DrawColourText = function(c,x,y,w,h,colour,tag,x1,y1) {
var normal = tag.colour;
tag.colour = colour;
tag.Draw(c,x1,y1);
tag.colour = normal;
return 1;
};
Oproto.DrawColourImage = function(c,x,y,w,h,colour,tag,x1,y1) {
var ccanvas = c.canvas, fx = ~~max(x,0), fy = ~~max(y,0),
fw = min(ccanvas.width - fx, w) + .5|0, fh = min(ccanvas.height - fy,h) + .5|0, cc;
if(ocanvas)
ocanvas.width = fw, ocanvas.height = fh;
else
ocanvas = NewCanvas(fw, fh);
if(!ocanvas)
return this.SetMethod('outline'); // if using IE and images, give up!
cc = ocanvas.getContext('2d');
cc.drawImage(ccanvas,fx,fy,fw,fh,0,0,fw,fh);
c.clearRect(fx,fy,fw,fh);
tag.Draw(c,x1,y1);
c.setTransform(1,0,0,1,0,0);
c.save();
c.beginPath();
c.rect(fx,fy,fw,fh);
c.clip();
c.globalCompositeOperation = 'source-in';
c.fillStyle = colour;
c.fillRect(fx,fy,fw,fh);
c.restore();
c.globalCompositeOperation = 'destination-over';
c.drawImage(ocanvas,0,0,fw,fh,fx,fy,fw,fh);
c.globalCompositeOperation = 'source-over';
return 1;
};
Oproto.DrawBlock = function(c,x,y,w,h,colour) {
c.fillStyle = colour;
c.fillRect(x,y,w,h);
};
Oproto.DrawSimple = function(c, tag, x1, y1) {
var t = this.tc;
c.setTransform(1,0,0,1,0,0);
c.strokeStyle = t.outlineColour;
c.lineWidth = t.outlineThickness;
c.shadowBlur = c.shadowOffsetX = c.shadowOffsetY = 0;
c.globalAlpha = 1;
return this.drawFunc(c,this.x,this.y,this.w,this.h,t.outlineColour,tag,x1,y1);
};
Oproto.DrawPulsate = function(c, tag, x1, y1) {
var diff = new Date().valueOf() - this.ts, t = this.tc;
c.setTransform(1,0,0,1,0,0);
c.strokeStyle = t.outlineColour;
c.lineWidth = t.outlineThickness;
c.shadowBlur = c.shadowOffsetX = c.shadowOffsetY = 0;
c.globalAlpha = t.pulsateTo + ((1 - t.pulsateTo) *
(0.5 + (cos(2 * Math.PI * diff / (1000 * t.pulsateTime)) / 2)));
return this.drawFunc(c,this.x,this.y,this.w,this.h,t.outlineColour,tag,x1,y1);
};
Oproto.Active = function(c,x,y) {
return (x >= this.x && y >= this.y &&
x <= this.x + this.w && y <= this.y + this.h);
};
Oproto.PreDraw = Oproto.PostDraw = Oproto.LastDraw = function() {};
/**
* @constructor
*/
function Tag(tc,name,a,v,w,h,col,font) {
var c = tc.ctxt, i;
this.tc = tc;
this.image = name.src ? name : null;
this.name = name.src ? '' : name;
this.title = a.title || null;
this.a = a;
this.p3d = { x: v[0] * tc.radius * 1.1, y: v[1] * tc.radius * 1.1, z: v[2] * tc.radius * 1.1};
this.x = this.y = 0;
this.w = w;
this.h = h;
this.colour = col || tc.textColour;
this.textFont = font || tc.textFont;
this.weight = this.sc = this.alpha = 1;
this.weighted = !tc.weight;
this.outline = new Outline(tc);
if(this.image) {
if(tc.txtOpt && tc.shadow) {
i = AddShadowToImage(this.image,tc.shadow,tc.shadowBlur,tc.shadowOffset);
if(i) {
this.image = i;
this.w = i.width;
this.h = i.height;
}
}
} else {
this.textHeight = tc.textHeight;
this.extents = FindTextBoundingBox(this.name, this.textFont, this.textHeight);
this.Measure(c,tc);
}
this.SetShadowColour = tc.shadowAlpha ? this.SetShadowColourAlpha : this.SetShadowColourFixed;
this.SetDraw(tc);
}
Tproto = Tag.prototype;
Tproto.SetDraw = function(t) {
this.Draw = this.image ? (t.ie > 7 ? this.DrawImageIE : this.DrawImage) : this.DrawText;
};
Tproto.Measure = function(c,t) {
this.h = this.extents ? this.extents.max.y + this.extents.min.y : this.textHeight;
c.font = this.font = this.textHeight + 'px ' + this.textFont;
this.w = c.measureText(this.name).width;
if(t.txtOpt) {
var s = t.txtScale, th = s * this.textHeight, f = th + 'px ' + this.textFont,
soff = [s*t.shadowOffset[0],s*t.shadowOffset[1]], cw;
c.font = f;
cw = c.measureText(this.name).width;
this.image = TextToCanvas(this.name, f, th, cw, s * this.h, this.colour,
t.shadow, s * t.shadowBlur, soff, s, s);
if(this.image) {
this.w = this.image.width / s;
this.h = this.image.height / s;
}
this.SetDraw(t);
t.txtOpt = this.image;
}
};
Tproto.SetWeight = function(w) {
this.weight = w;
this.Weight(this.tc.ctxt, this.tc);
this.Measure(this.tc.ctxt, this.tc);
};
Tproto.Weight = function(c,t) {
var w = this.weight, m = t.weightMode;
this.weighted = true;
if(m == 'colour' || m == 'both')
this.colour = FindGradientColour(t, (w - t.min_weight) / (t.max_weight-t.min_weight));
if(m == 'size' || m == 'both')
this.textHeight = w * t.weightSize;
this.extents = FindTextBoundingBox(this.name, this.textFont, this.textHeight);
};
Tproto.SetShadowColourFixed = function(c,s,a) {
c.shadowColor = s;
};
Tproto.SetShadowColourAlpha = function(c,s,a) {
c.shadowColor = SetAlpha(s, a);
};
Tproto.DrawText = function(c,xoff,yoff) {
var t = this.tc, x = this.x, y = this.y, w, h, s = this.sc;
c.globalAlpha = this.alpha;
c.setTransform(s,0,0,s,0,0);
c.fillStyle = this.colour;
t.shadow && this.SetShadowColour(c,t.shadow,this.alpha);
c.font = this.font;
w = this.w;
h = this.h;
x += (xoff / s) - (w / 2);
y += (yoff / s) - (h / 2);
c.fillText(this.name, x, y);
};
Tproto.DrawImage = function(c,xoff,yoff) {
var t = this.tc, x = this.x, y = this.y, s = this.sc,
i = this.image, w = this.w, h = this.h, a = this.alpha,
shadow = this.shadow;
c.globalAlpha = a;
c.setTransform(s,0,0,s,0,0);
c.fillStyle = this.colour;
shadow && this.SetShadowColour(c,shadow,a);
x += (xoff / s) - (w / 2);
y += (yoff / s) - (h / 2);
c.drawImage(i, x, y, w, h);
};
Tproto.DrawImageIE = function(c,xoff,yoff) {
var i = this.image, s = this.sc,
w = i.width = this.w*s, h = i.height = this.h * s,
x = (this.x*s) + xoff - (w/2), y = (this.y*s) + yoff - (h/2);
c.setTransform(1,0,0,1,0,0);
c.globalAlpha = this.alpha;
c.drawImage(i, x, y);
};
Tproto.Calc = function(yaw,pitch) {
var pp = RotY(this.p3d,yaw), t = this.tc, mb = t.minBrightness, r = t.radius;
this.p3d = RotX(pp,pitch);
pp = Project(t, this.p3d, this.w, this.h, Math.PI / 4, 20);
this.x = pp.x;
this.y = pp.y;
this.sc = (t.z1 + t.z2 - pp.z) / t.z2;
this.alpha = max(mb,min(1,mb + 1 - ((pp.z - t.z2 + r) / (2 * r))));
};
Tproto.CheckActive = function(c,xoff,yoff) {
var t = this.tc, o = this.outline,
w = this.w, h = this.h,
x = this.x - w/2, y = this.y - h/2;
o.Update(x, y, w, h, this.sc, this.p3d, xoff, yoff);
return o.Active(c, t.mx, t.my) ? o : null;
};
Tproto.Clicked = function(e) {
var a = this.a, t = a.target, h = a.href, evt;
if(t != '' && t != '_self') {
if(self.frames[t])
self.frames[t] = h;
else if(top.frames[t])
top.frames[t] = h;
else
window.open(h, t);
return;
}
if(a.fireEvent) {
if(!a.fireEvent('onclick'))
return;
} else {
evt = doc.createEvent('MouseEvents');
evt.initMouseEvent('click', 1, 1, window, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, null);
if(!a.dispatchEvent(evt))
return;
}
doc.location = h;
};
/**
* @constructor
*/
function TagCanvas(cid,lctr,opt) {
var i, ctr, tl, vl, p, im, ii, tag, c = doc.getElementById(cid),
cp = ['id','class','innerHTML'], w, weights = [],
pfuncs = {
sphere:PointsOnSphere,
vcylinder:PointsOnCylinderV,
hcylinder:PointsOnCylinderH
};
if(!c) throw 0;
if(Defined(window.G_vmlCanvasManager)) {
c = window.G_vmlCanvasManager.initElement(c);
this.ie = parseFloat(navigator.appVersion.split('MSIE')[1]);
}
if(c && (!c.getContext || !c.getContext('2d').fillText)) {
p = doc.createElement('DIV');
for(i = 0; i < cp.length; ++i)
p[cp[i]] = c[cp[i]];
c.parentNode.insertBefore(p,c);
c.parentNode.removeChild(c);
throw 0;
}
for(i in TagCanvas.options)
this[i] = opt && Defined(opt[i]) ? opt[i] :
(Defined(TagCanvas[i]) ? TagCanvas[i] : TagCanvas.options[i]);
this.canvas = c;
this.ctxt = c.getContext('2d');
this.z1 = (19800 / (Math.exp(this.depth) * (1-1/Math.E))) +
20000 - 19800 / (1-(1/Math.E));
this.z2 = this.z1 * (1/this.zoom);
this.radius = (c.height > c.width ? c.width : c.height)
* 0.33 * (this.z2 + this.z1) / (this.z1);
this.max_weight = 0;
this.min_weight = 200;
this.textFont = this.textFont && FixFont(this.textFont);
this.pulsateTo *= 1;
this.textHeight *= 1;
this.minBrightness *= 1;
this.ctxt.textBaseline = 'top';
if(this.shadowBlur || this.shadowOffset[0] || this.shadowOffset[1]) {
// let the browser translate "red" into "#ff0000"
this.ctxt.shadowColor = this.shadow;
this.shadow = this.ctxt.shadowColor;
this.shadowAlpha = ShadowAlphaBroken();
} else {
delete this.shadow;
}
try {
ctr = doc.getElementById(lctr || cid);
tl = ctr.getElementsByTagName('a');
this.taglist = [];
if(tl.length) {
this.shape = pfuncs[this.shape] || pfuncs.sphere;
vl = this.shape(tl.length);
for(i = 0; i < tl.length; ++i) {
im = tl[i].getElementsByTagName('img');
if(im.length) {
ii = new Image;
ii.src = im[0].src;
tag = new Tag(this, ii, tl[i], vl[i], 1, 1);
AddImage(ii,tag,this.taglist);
} else {
this.taglist.push(new Tag(this, tl[i].innerText || tl[i].textContent, tl[i],
vl[i], 2, this.textHeight + 2, this.textColour || GetProperty(tl[i],'color'),
this.textFont || FixFont(GetProperty(tl[i],'font-family'))));
}
if(this.weight) {
w = FindWeight(this,tl[i]);
if(w > this.max_weight) this.max_weight = w;
if(w < this.min_weight) this.min_weight = w;
weights.push(w);
}
}
if(this.weight = (this.max_weight > this.min_weight)) {
for(i = 0; i < this.taglist.length; ++i) {
this.taglist[i].SetWeight(weights[i]);
}
}
}
if(lctr && this.hideTags)
ctr.style.display = 'none';
} catch(ex) {
ex;
}
this.yaw = this.initial ? this.initial[0] * this.maxSpeed : 0;
this.pitch = this.initial ? this.initial[1] * this.maxSpeed : 0;
if(this.tooltip) {
if(this.tooltip == 'native') {
this.Tooltip = this.TooltipNative;
} else {
this.Tooltip = this.TooltipDiv;
if(!this.ttdiv) {
this.ttdiv = doc.createElement('div');
this.ttdiv.className = this.tooltipClass;
this.ttdiv.style.position = 'absolute';
this.ttdiv.style.zIndex = c.style.zIndex + 1;
AddHandler('mouseover',function(e){e.target.style.display='none';},this.ttdiv);
doc.body.appendChild(this.ttdiv);
}
}
} else {
this.Tooltip = this.TooltipNone;
}
AddHandler('mousemove', MouseMove, c);
AddHandler('mouseout', MouseMove, c);
AddHandler('mouseup', MouseClick, c);
if(this.wheelZoom) {
AddHandler('mousewheel', MouseWheel, c);
AddHandler('DOMMouseScroll', MouseWheel, c);
}
TagCanvas.started || (TagCanvas.started = setInterval(DrawCanvas, this.interval));
}
TCproto = TagCanvas.prototype;
TCproto.Draw = function() {
var cv = this.canvas, cw = cv.width, ch = cv.height, max_sc = 0, yaw = this.yaw, pitch = this.pitch,
x1 = cw / 2, y1 = ch / 2, c = this.ctxt, active, a, i, aindex = -1, tl = this.taglist, l = tl.length,
frontsel = this.frontSelect;
if(yaw == 0 && pitch == 0 && this.drawn)
return this.Animate(cw,ch);
c.setTransform(1,0,0,1,0,0);
this.active = null;
for(i = 0; i < l; ++i)
tl[i].Calc(yaw, pitch);
tl = tl.sort(function(a,b) {return a.sc-b.sc});
for(i = 0; i < l; ++i) {
a = tl[i].CheckActive(c, x1, y1);
if(a && a.sc > max_sc && (!frontsel || a.z <= 0)) {
active = a;
active.index = aindex = i;
max_sc = a.sc;
}
}
this.active = active;
if(!this.txtOpt && this.shadow) {
c.shadowBlur = this.shadowBlur;
c.shadowOffsetX = this.shadowOffset[0];
c.shadowOffsetY = this.shadowOffset[1];
}
c.clearRect(0,0,cw,ch);
for(i = 0; i < l; ++i) {
if(!(aindex == i && active.PreDraw(c, tl[i], x1, y1)))
tl[i].Draw(c, x1, y1);
aindex == i && active.PostDraw(c);
}
if(this.freezeActive && active) {
this.yaw = this.pitch = this.drawn = 0;
} else {
this.Animate(cw, ch);
this.drawn = 1;
}
active && active.LastDraw(c);
cv.style.cursor = active ? this.activeCursor : '';
this.Tooltip(active,tl[aindex]);
};
TCproto.TooltipNone = function() { };
TCproto.TooltipNative = function(active,tag) {
this.canvas.title = active && tag.title ? tag.title : '';
};
TCproto.TooltipDiv = function(active,tag) {
var tc = this, s = tc.ttdiv.style, cid = tc.canvas.id;
if(active && tag.title) {
tc.ttdiv.innerHTML = tag.title;
if(s.display == 'none' && ! tc.tttimer) {
tc.tttimer = setTimeout(function() {
var p = AbsPos(cid);
s.display = 'block';
s.left = p.x + tc.mx + 'px';
s.top = p.y + tc.my + 24 + 'px';
tc.tttimer = null;
}, tc.tooltipDelay);
}
} else {
s.display = 'none';
}
};
TCproto.Animate = function(w,h) {
var tc = this, x = tc.mx, y = tc.my, l = tc.lock, s, ay, ap, r;
if(x >= 0 && y >= 0 && x < w && y < h)
{
s = tc.maxSpeed, r = tc.reverse ? -1 : 1;
if(l != 'x')
this.yaw = r * ((s * 2 * x / w) - s);
if(l != 'y')
this.pitch = r * -((s * 2 * y / h) - s);
this.initial = null;
}
else if(!tc.initial)
{
s = tc.minSpeed, ay = abs(tc.yaw), ap = abs(tc.pitch);
if(l != 'x' && ay > s)
this.yaw = ay > tc.z0 ? tc.yaw * tc.decel : 0;
if(l != 'y' && ap > s)
this.pitch = ap > tc.z0 ? tc.pitch * tc.decel : 0;
}
};
TCproto.Zoom = function(r) {
this.z2 = this.z1 * (1/r);
this.drawn = 0;
};
TCproto.Clicked = function(e) {
var t = this.taglist, a = this.active;
try {
if(a && t[a.index])
t[a.index].Clicked(e);
} catch(ex) {
}
};
TCproto.Wheel = function(i) {
var z = this.zoom + this.zoomStep * (i ? 1 : -1);
this.zoom = min(this.zoomMax,max(this.zoomMin,z));
this.Zoom(this.zoom);
};
TagCanvas.Start = function(id,l,o) {
TagCanvas.tc[id] = new TagCanvas(id,l,o);
};
TagCanvas.tc = {};
TagCanvas.options = {
z1: 20000,
z2: 20000,
z0: 0.0002,
freezeActive: false,
activeCursor: 'pointer',
pulsateTo: 1,
pulsateTime: 3,
reverse: false,
depth: 0.5,
maxSpeed: 0.05,
minSpeed: 0,
decel: 0.95,
interval: 20,
minBrightness: 0.1,
outlineColour: '#ffff99',
outlineThickness: 2,
outlineOffset: 5,
outlineMethod: 'outline',
textColour: '#ff99ff',
textHeight: 15,
textFont: 'Helvetica, Arial, sans-serif',
shadow: '#000',
shadowBlur: 0,
shadowOffset: [0,0],
initial: null,
hideTags: true,
zoom: 1,
weight: false,
weightMode: 'size',
weightFrom: null,
weightSize: 1,
weightGradient: {0:'#f00', 0.33:'#ff0', 0.66:'#0f0', 1:'#00f'},
txtOpt: true,
txtScale: 2,
frontSelect: false,
wheelZoom: true,
zoomMin: 0.3,
zoomMax: 3,
zoomStep: 0.05,
shape: 'sphere',
lock: null,
tooltip: null,
tooltipDelay: 300,
tooltipClass: 'tctooltip'
};
for(i in TagCanvas.options) TagCanvas[i] = TagCanvas.options[i];
window.TagCanvas = TagCanvas;
})();
第二种：使用setInterval+定位
第三种：使用marquee + 定位
总结：
1、使用setInterval+定位+svg实现的方式，页面滚动速度慢时会有轻微抖动出现。
2、使用marguee+定位实现没有抖动且方向、速度也可以控制，但是页面初次渲染会有一点点空白，因为元素还没有滚动出来。
3、使用tagcanvas实现的效果比较好些，没有抖动，速度、方向等也可以控制。