一个可以在页面上随意画线、多边形、圆,填充等功能的js

类别:.NET开发 点击:0 评论:0 推荐:

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);
}





function mkOv2D(left, top, width, height)
{
var s = this.stroke;
width += s-1;
height += s-1;
var a = width>>1, b = height>>1,
wod = width&1, hod = (height&1)+1,
cx = left+a, cy = top+b,
x = 0, y = b,
aa = (a*a)<<1, bb = (b*b)<<1,
st = (aa>>1)*(1-(b<<1)) + bb,
tt = (bb>>1) - aa*((b<<1)-1);

if (s-4 < 0 && (!(s-2) || width-51 > 0 && height-51 > 0))
{
var ox = 0, oy = b,
w, h,
pxl, pxr, pxt, pxb, pxw;
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-1)
{
pxw = w+1+(s&1);
h = s;
}
else if (h-1)
{
pxw = s;
h += 1+(s&1);
}
else pxw = h = s;
this.mkOvQds(cx, cy, -x+1, ox-pxw+w+wod, -oy, -h+oy+hod, pxw, h);
ox = x;
oy = y;
}
else
{
tt -= aa*((y<<1)-3);
st -= (aa<<1)*(--y);
}
}
this.mkDiv(cx-a, cy-oy, s, (oy<<1)+hod);
this.mkDiv(cx+a+wod-s+1, cy-oy, s, (oy<<1)+hod);
}

else
{
var _a = (width-((s-1)<<1))>>1,
_b = (height-((s-1)<<1))>>1,
_x = 0, _y = _b,
_aa = (_a*_a)<<1, _bb = (_b*_b)<<1,
_st = (_aa>>1)*(1-(_b<<1)) + _bb,
_tt = (_bb>>1) - _aa*((_b<<1)-1),

pxl = new Array(),
pxt = new Array(),
_pxb = new Array();
pxl[0] = 0;
pxt[0] = b;
_pxb[0] = _b-1;
while (y > 0)
{
if (st < 0)
{
st += bb*((x<<1)+3);
tt += (bb<<1)*(++x);
pxl[pxl.length] = x;
pxt[pxt.length] = y;
}
else if (tt < 0)
{
st += bb*((x<<1)+3) - (aa<<1)*(y-1);
tt += (bb<<1)*(++x) - aa*(((y--)<<1)-3);
pxl[pxl.length] = x;
pxt[pxt.length] = y;
}
else
{
tt -= aa*((y<<1)-3);
st -= (aa<<1)*(--y);
}

if (_y > 0)
{
if (_st < 0)
{
_st += _bb*((_x<<1)+3);
_tt += (_bb<<1)*(++_x);
_pxb[_pxb.length] = _y-1;
}
else if (_tt < 0)
{
_st += _bb*((_x<<1)+3) - (_aa<<1)*(_y-1);
_tt += (_bb<<1)*(++_x) - _aa*(((_y--)<<1)-3);
_pxb[_pxb.length] = _y-1;
}
else
{
_tt -= _aa*((_y<<1)-3);
_st -= (_aa<<1)*(--_y);
_pxb[_pxb.length-1]--;
}
}
}

var ox = 0, oy = b,
_oy = _pxb[0],
l = pxl.length,
w, h;
for (var i = 0; i < l; i++)
{
if (typeof _pxb[i] != "undefined")
{
if (_pxb[i] < _oy || pxt[i] < oy)
{
x = pxl[i];
this.mkOvQds(cx, cy, -x+1, ox+wod, -oy, _oy+hod, x-ox, oy-_oy);
ox = x;
oy = pxt[i];
_oy = _pxb[i];
}
}
else
{
x = pxl[i];
this.mkDiv(cx-x+1, cy-oy, 1, (oy<<1)+hod);
this.mkDiv(cx+ox+wod, cy-oy, 1, (oy<<1)+hod);
ox = x;
oy = pxt[i];
}
}
this.mkDiv(cx-a, cy-oy, 1, (oy<<1)+hod);
this.mkDiv(cx+ox+wod, cy-oy, 1, (oy<<1)+hod);
}
}


function mkOvDott(left, top, width, height)
{
var a = width>>1, b = height>>1,
wod = width&1, hod = height&1,
cx = left+a, cy = top+b,
x = 0, y = b,
aa2 = (a*a)<<1, aa4 = aa2<<1, bb = (b*b)<<1,
st = (aa2>>1)*(1-(b<<1)) + bb,
tt = (bb>>1) - aa2*((b<<1)-1),
drw = true;
while (y > 0)
{
if (st < 0)
{
st += bb*((x<<1)+3);
tt += (bb<<1)*(++x);
}
else if (tt < 0)
{
st += bb*((x<<1)+3) - aa4*(y-1);
tt += (bb<<1)*(++x) - aa2*(((y--)<<1)-3);
}
else
{
tt -= aa2*((y<<1)-3);
st -= aa4*(--y);
}
if (drw) this.mkOvQds(cx, cy, -x, x+wod, -y, y+hod, 1, 1);
drw = !drw;
}
}







function mkRect(x, y, w, h)
{
var s = this.stroke;
this.mkDiv(x, y, w, s);
this.mkDiv(x+w, y, s, h);
this.mkDiv(x, y+h, w+s, s);
this.mkDiv(x, y+s, s, h-s);
}


function mkRectDott(x, y, w, h)
{
this.drawLine(x, y, x+w, y);
this.drawLine(x+w, y, x+w, y+h);
this.drawLine(x, y+h, x+w, y+h);
this.drawLine(x, y, x, y+h);
}


function jsgFont()
{
this.PLAIN = 'font-weight:normal;';
this.BOLD = 'font-weight:bold;';
this.ITALIC = 'font-style:italic;';
this.ITALIC_BOLD = this.ITALIC + this.BOLD;
this.BOLD_ITALIC = this.ITALIC_BOLD;
}
var Font = new jsgFont();


function jsgStroke()
{
this.DOTTED = -1;
}
var Stroke = new jsgStroke();


function jsGraphics(id, wnd)
{
this.setColor = new Function('arg', 'this.color = arg.toLowerCase();');

this.setStroke = function(x)
{
this.stroke = x;
if (!(x+1))
{
this.drawLine = mkLinDott;
this.mkOv = mkOvDott;
this.drawRect = mkRectDott;
}
else if (x-1 > 0)
{
this.drawLine = mkLin2D;
this.mkOv = mkOv2D;
this.drawRect = mkRect;
}
else
{
this.drawLine = mkLin;
this.mkOv = mkOv;
this.drawRect = mkRect;
}
};


this.setPrintable = function(arg)
{
this.printable = arg;
if (jg_fast)
{
this.mkDiv = mkDivIe;
this.htmRpc = arg? htmPrtRpc : htmRpc;
}
else this.mkDiv = jg_n4? mkLyr : arg? mkDivPrt : mkDiv;
};


this.setFont = function(fam, sz, sty)
{
this.ftFam = fam;
this.ftSz = sz;
this.ftSty = sty || Font.PLAIN;
};


this.drawPolyline = this.drawPolyLine = function(x, y, s)
{
for (var i=0 ; i<x.length-1 ; i++ )
this.drawLine(x[i], y[i], x[i+1], y[i+1]);
};


this.fillRect = function(x, y, w, h)
{
this.mkDiv(x, y, w, h);
};


this.drawPolygon = function(x, y)
{
this.drawPolyline(x, y);
this.drawLine(x[x.length-1], y[x.length-1], x[0], y[0]);
};


this.drawEllipse = this.drawOval = function(x, y, w, h)
{
this.mkOv(x, y, w, h);
};


this.fillEllipse = this.fillOval = function(left, top, w, h)
{
var a = (w -= 1)>>1, b = (h -= 1)>>1,
wod = (w&1)+1, hod = (h&1)+1,
cx = left+a, cy = top+b,
x = 0, y = b,
ox = 0, oy = b,
aa2 = (a*a)<<1, aa4 = aa2<<1, bb = (b*b)<<1,
st = (aa2>>1)*(1-(b<<1)) + bb,
tt = (bb>>1) - aa2*((b<<1)-1),
pxl, dw, dh;
if (w+1) while (y > 0)
{
if (st < 0)
{
st += bb*((x<<1)+3);
tt += (bb<<1)*(++x);
}
else if (tt < 0)
{
st += bb*((x<<1)+3) - aa4*(y-1);
pxl = cx-x;
dw = (x<<1)+wod;
tt += (bb<<1)*(++x) - aa2*(((y--)<<1)-3);
dh = oy-y;
this.mkDiv(pxl, cy-oy, dw, dh);
this.mkDiv(pxl, cy+oy-dh+hod, dw, dh);
ox = x;
oy = y;
}
else
{
tt -= aa2*((y<<1)-3);
st -= aa4*(--y);
}
}
this.mkDiv(cx-a, cy-oy, w+1, (oy<<1)+hod);
};

this.fillPolygon = function(array_x, array_y)
{
var i;
var y;
var miny, maxy;
var x1, y1;
var x2, y2;
var ind1, ind2;
var ints;

var n = array_x.length;

if (!n) return;


miny = array_y[0];
maxy = array_y[0];
for (i = 1; i < n; i++)
{
if (array_y[i] < miny)
miny = array_y[i];

if (array_y[i] > maxy)
maxy = array_y[i];
}
for (y = miny; y <= maxy; y++)
{
var polyInts = new Array();
ints = 0;
for (i = 0; i < n; i++)
{
if (!i)
{
ind1 = n-1;
ind2 = 0;
}
else
{
ind1 = i-1;
ind2 = i;
}
y1 = array_y[ind1];
y2 = array_y[ind2];
if (y1 < y2)
{
x1 = array_x[ind1];
x2 = array_x[ind2];
}
else if (y1 > y2)
{
y2 = array_y[ind1];
y1 = array_y[ind2];
x2 = array_x[ind1];
x1 = array_x[ind2];
}
else continue;

if ((y >= y1) && (y < y2))
polyInts[ints++] = Math.round((y-y1) * (x2-x1) / (y2-y1) + x1);

else if ((y == maxy) && (y > y1) && (y <= y2))
polyInts[ints++] = Math.round((y-y1) * (x2-x1) / (y2-y1) + x1);
}
polyInts.sort(integer_compare);

for (i = 0; i < ints; i+=2)
{
w = polyInts[i+1]-polyInts[i]
this.mkDiv(polyInts[i], y, polyInts[i+1]-polyInts[i]+1, 1);
}
}
};


this.drawString = function(txt, x, y)
{
this.htm += '<div style="position:absolute;white-space:nowrap;'+
'left:' + x + 'px;'+
'top:' + y + 'px;'+
'font-family:' +  this.ftFam + ';'+
'font-size:' + this.ftSz + ';'+
'color:' + this.color + ';' + this.ftSty + '">'+
txt +
'<\/div>';
}


this.drawImage = function(imgSrc, x, y, w, h)
{
this.htm += '<div style="position:absolute;'+
'left:' + x + 'px;'+
'top:' + y + 'px;'+
'width:' +  w + ';'+
'height:' + h + ';">'+
'<img src="' + imgSrc + '" width="' + w + '" height="' + h + '">'+
'<\/div>';
}


this.clear = function()
{
this.htm = "";
if (this.cnv) this.cnv.innerHTML = this.defhtm;
};


this.mkOvQds = function(cx, cy, xl, xr, yt, yb, w, h)
{
this.mkDiv(xr+cx, yt+cy, w, h);
this.mkDiv(xr+cx, yb+cy, w, h);
this.mkDiv(xl+cx, yb+cy, w, h);
this.mkDiv(xl+cx, yt+cy, w, h);
};

this.setStroke(1);
this.setFont('verdana,geneva,helvetica,sans-serif', String.fromCharCode(0x31, 0x32, 0x70, 0x78), Font.PLAIN);
this.color = '#000000';
this.htm = '';
this.wnd = wnd || window;

if (!(jg_ie || jg_dom || jg_ihtm)) chkDHTM();
if (typeof id != 'string' || !id) this.paint = pntDoc;
else
{
this.cnv = document.all? (this.wnd.document.all[id] || null)
: document.getElementById? (this.wnd.document.getElementById(id) || null)
: null;
this.defhtm = (this.cnv && this.cnv.innerHTML)? this.cnv.innerHTML : '';
this.paint = jg_dom? pntCnvDom : jg_ie? pntCnvIe : jg_ihtm? pntCnvIhtm : pntCnv;
}

this.setPrintable(false);
}

function integer_compare(x,y)
{
return (x < y) ? -1 : ((x > y)*1);
}

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