// 6
一個可以在頁面上隨意畫線、多邊形、圓,填充等功能的js (part 1)
var jg_ihtm, jg_ie, jg_fast, jg_dom, jg_moz,
jg_n4 = (document.layers && typeof document.classes != "undefined");
function chkDHTM(x, i)
{
x = document.body || null;
jg_ie = x && typeof x.insertAdjacentHTML != "undefined";
jg_dom = (x && !jg_ie &&
typeof x.appendChild != "undefined" &&
typeof document.createRange != "undefined" &&
typeof (i = document.createRange()).setStartBefore != "undefined" &&
typeof i.createContextualFragment != "undefined");
jg_ihtm = !jg_ie && !jg_dom && x && typeof x.innerHTML != "undefined";
jg_fast = jg_ie && document.all && !window.opera;
jg_moz = jg_dom && typeof x.style.MozOpacity != "undefined";
}
function pntDoc()
{
this.wnd.document.write(jg_fast? this.htmRpc() : this.htm);
this.htm = ’’;
}
function pntCnvDom()
{
var x = document.createRange();
x.setStartBefore(this.cnv);
x = x.createContextualFragment(jg_fast? this.htmRpc() : this.htm);
this.cnv.appendChild(x);
this.htm = ’’;
}
function pntCnvIe()
{
this.cnv.insertAdjacentHTML("BeforeEnd", jg_fast? this.htmRpc() : this.htm);
this.htm = ’’;
}
function pntCnvIhtm()
{
this.cnv.innerHTML += this.htm;
this.htm = ’’;
}
function pntCnv()
{
this.htm = ’’;
}
function mkDiv(x, y, w, h)
{
this.htm += ’<div style="position:absolute;’+
’left:’ + x + ’px;’+
’top:’ + y + ’px;’+
’width:’ + w + ’px;’+
’height:’ + h + ’px;’+
’clip:rect(0,’+w+’px,’+h+’px,0);’+
’background-color:’ + this.color +
(!jg_moz? ’;overflow:hidden’ : ’’)+
’;"><//div>’;
}
function mkDivIe(x, y, w, h)
{
this.htm += ’%%’+this.color+’;’+x+’;’+y+’;’+w+’;’+h+’;’;
}
function mkDivPrt(x, y, w, h)
{
this.htm += ’<div style="position:absolute;’+
’border-left:’ + w + ’px solid ’ + this.color + ’;’+
’left:’ + x + ’px;’+
’top:’ + y + ’px;’+
’width:0px;’+
’height:’ + h + ’px;’+
’clip:rect(0,’+w+’px,’+h+’px,0);’+
’background-color:’ + this.color +
(!jg_moz? ’;overflow:hidden’ : ’’)+
’;"><//div>’;
}
function mkLyr(x, y, w, h)
{
this.htm += ’<layer ’+
’left="’ + x + ’" ’+
’top="’ + y + ’" ’+
’width="’ + w + ’" ’+
’height="’ + h + ’" ’+
’bgcolor="’ + this.color + ’"><//layer>/n’;
}
var regex = /%%([^;]+);([^;]+);([^;]+);([^;]+);([^;]+);/g;
function htmRpc()
{
return this.htm.replace(
regex,
’<div style="overflow:hidden;position:absolute;background-color:’+
’$1;left:$2;top:$3;width:$4;height:$5"></div>/n’);
}
function htmPrtRpc()
{
return this.htm.replace(
regex,
’<div style="overflow:hidden;position:absolute;background-color:’+
’$1;left:$2;top:$3;width:$4;height:$5;border-left:$4px solid $1"></div>/n’);
}
function mkLin(x1, y1, x2, y2)
{
if (x1 > x2)
{
var _x2 = x2;
var _y2 = y2;
x2 = x1;
y2 = y1;
x1 = _x2;
y1 = _y2;
}
var dx = x2-x1, dy = Math.abs(y2-y1),
x = x1, y = y1,
yIncr = (y1 > y2)? -1 : 1;
if (dx >= dy)
{
var pr = dy<<1,
pru = pr - (dx<<1),
p = pr-dx,
ox = x;
while ((dx--) > 0)
{
++x;
if (p > 0)
{
this.mkDiv(ox, y, x-ox, 1);
y += yIncr;
p += pru;
ox = x;
}
else p += pr;
}
this.mkDiv(ox, y, x2-ox+1, 1);
}
else
{
var pr = dx<<1,
pru = pr - (dy<<1),
p = pr-dy,
oy = y;
if (y2 <= y1)
{
while ((dy--) > 0)
{
if (p > 0)
{
this.mkDiv(x++, y, 1, oy-y+1);
y += yIncr;
p += pru;
oy = y;
}
else
{
y += yIncr;
p += pr;
}
}
this.mkDiv(x2, y2, 1, oy-y2+1);
}
else
{
while ((dy--) > 0)
{
y += yIncr;
if (p > 0)
{
this.mkDiv(x++, oy, 1, y-oy);
p += pru;
oy = y;
}
else p += pr;
}
this.mkDiv(x2, oy, 1, y2-oy+1);
}
}
}
function mkLin2D(x1, y1, x2, y2)
{
if (x1 > x2)
{
var _x2 = x2;
var _y2 = y2;
x2 = x1;
y2 = y1;
x1 = _x2;
y1 = _y2;
}
var dx = x2-x1, dy = Math.abs(y2-y1),
x = x1, y = y1,
yIncr = (y1 > y2)? -1 : 1;
var s = this.stroke;
if (dx >= dy)
{
if (s-3 > 0)
{
var _s = (s*dx*Math.sqrt(1+dy*dy/(dx*dx))-dx-(s>>1)*dy) / dx;
_s = (!(s-4)? Math.ceil(_s) : Math.round(_s)) + 1;
}
else var _s = s;
var ad = Math.ceil(s/2);
var pr = dy<<1,
pru = pr - (dx<<1),
p = pr-dx,
ox = x;
while ((dx--) > 0)
{
++x;
if (p > 0)
{
this.mkDiv(ox, y, x-ox+ad, _s);
y += yIncr;
p += pru;
ox = x;
}
else p += pr;
}
this.mkDiv(ox, y, x2-ox+ad+1, _s);
}
else
{
if (s-3 > 0)
{
var _s = (s*dy*Math.sqrt(1+dx*dx/(dy*dy))-(s>>1)*dx-dy) / dy;
_s = (!(s-4)? Math.ceil(_s) : Math.round(_s)) + 1;
}
else var _s = s;
var ad = Math.round(s/2);
var pr = dx<<1,
pru = pr - (dy<<1),
p = pr-dy,
oy = y;
if (y2 <= y1)
{
++ad;
while ((dy--) > 0)
{
if (p > 0)
{
this.mkDiv(x++, y, _s, oy-y+ad);
y += yIncr;
p += pru;
oy = y;
}
else
{
y += yIncr;
p += pr;
}
}
this.mkDiv(x2, y2, _s, oy-y2+ad);
}
else
{
while ((dy--) > 0)
{
y += yIncr;
if (p > 0)
{
this.mkDiv(x++, oy, _s, y-oy+ad);
p += pru;
oy = y;
}
else p += pr;
}
this.mkDiv(x2, oy, _s, y2-oy+ad+1);
}
}
}
function mkLinDott(x1, y1, x2, y2)
{
if (x1 > x2)
{
var _x2 = x2;
var _y2 = y2;
x2 = x1;
y2 = y1;
x1 = _x2;
y1 = _y2;
}
var dx = x2-x1, dy = Math.abs(y2-y1),
x = x1, y = y1,
yIncr = (y1 > y2)? -1 : 1,
drw = true;
if (dx >= dy)
{
var pr = dy<<1,
pru = pr - (dx<<1),
p = pr-dx;
while ((dx--) > 0)
{
if (drw) this.mkDiv(x, y, 1, 1);
drw = !drw;
if (p > 0)
{
y += yIncr;
p += pru;
}
else p += pr;
++x;
}
if (drw) this.mkDiv(x, y, 1, 1);
}
else
{
var pr = dx<<1,
pru = pr - (dy<<1),
p = pr-dy;
while ((dy--) > 0)
{
if (drw) this.mkDiv(x, y, 1, 1);
drw = !drw;
y += yIncr;
if (p > 0)
{
++x;
p += pru;
}
else p += pr;
}
if (drw) this.mkDiv(x, y, 1, 1);
}
}
function mkOv(left, top, width, height)
{
var a = width>>1, b = height>>1,
wod = width&1, hod = (height&1)+1,
cx = left+a, cy = top+b,
x = 0, y = b,
ox = 0, oy = b,
aa = (a*a)<<1, bb = (b*b)<<1,
st = (aa>>1)*(1-(b<<1)) + bb,
tt = (bb>>1) - aa*((b<<1)-1),
w, h;
while (y > 0)
{
if (st < 0)
{
st += bb*((x<<1)+3);
tt += (bb<<1)*(++x);
}
else if (tt < 0)
{
st += bb*((x<<1)+3) - (aa<<1)*(y-1);
tt += (bb<<1)*(++x) - aa*(((y--)<<1)-3);
w = x-ox;
h = oy-y;
if (w&2 && h&2)
{
this.mkOvQds(cx, cy, -x+2, ox+wod, -oy, oy-1+hod, 1, 1);
this.mkOvQds(cx, cy, -x+1, x-1+wod, -y-1, y+hod, 1, 1);
}
else this.mkOvQds(cx, cy, -x+1, ox+wod, -oy, oy-h+hod, w, h);
ox = x;
oy = y;
}
else
{
tt -= aa*((y<<1)-3);
st -= (aa<<1)*(--y);
}
}
this.mkDiv(cx-a, cy-oy, a-ox+1, (oy<<1)+hod);
this.mkDiv(cx+ox+wod, cy-oy, a-ox+1, (oy<<1)+hod);
}