如何为 svg 路径的渐进式绘制动画？
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【中文标题】如何为 svg 路径的渐进式绘制动画？【英文标题】：How can I animate a progressive drawing of svg path? 【发布时间】：2012-12-25 20:42:58 【问题描述】：我想仅使用带有 svg/canvas 和 js 的 css 来为线条的渐进式绘制动画。我想画的线的想法可以找到here
<svg xmlns="http://www.w3.org/2000/svg">
<!-- Created with SVG-edit - http://svg-edit.googlecode.com/ -->
<g>
<title>Layer 1</title>
<path d="m33,104c1,0 2.1306,-0.8037 23,3c9.07012,1.65314 10,2 24,2c7,0 29,0 33,0c8,0 9,0 11,0c2,0 8,0 11,0c9,0 17,0 18,0c10,0 12,0 20,0c1,0 6,0 7,0c2,0 3.07613,0.38268 4,0c2.61313,-1.08239 2,-3 2,-6c0,-1 0,-2 0,-3c0,-1 0,-2 0,-3c0,-1 0,-2 0,-3c0,-1 0.30745,-3.186 -1,-5c-0.8269,-1.14727 -0.09789,-2.82443 -2,-4c-0.85065,-0.52573 -2.82443,-0.09789 -4,-2c-0.52573,-0.85065 -2.58578,-0.58578 -4,-2c-0.70711,-0.70711 -1.81265,-1.20681 -4,-3c-2.78833,-2.28588 -3.64749,-2.97251 -8,-4c-2.91975,-0.68926 -4.82375,-2.48626 -7,-3c-2.91975,-0.68926 -5.15224,-0.23463 -7,-1c-1.30656,-0.5412 -4.38687,-1.91761 -7,-3c-1.84776,-0.76537 -5.03609,0.37821 -7,0c-5.28799,-1.01837 -8,-3 -9,-3c-2,0 -5.0535,-0.54049 -7,-1c-2.17625,-0.51374 -4.15224,-0.23463 -6,-1c-1.30656,-0.54119 -3,-1 -4,-1c-2,0 -5,-1 -6,-1c-1,0 -3,-2 -6,-2c-2,0 -5,-2 -6,-2c-2,0 -2.02583,-0.67963 -4,-1c-3.12144,-0.50654 -4.15224,-0.23463 -6,-1c-1.30656,-0.54119 -2,-1 -3,-1c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-1,0 -2,0 -3,0c-1,0 -2,0 -3,0c-2,0 -3.85273,0.1731 -5,1c-1.81399,1.30745 -5.18601,1.69255 -7,3c-1.14727,0.8269 -1.82375,2.48626 -4,3c-0.97325,0.22975 -1.69344,1.45881 -3,2c-0.92388,0.38268 -1.45951,1.0535 -1,3c0.51374,2.17625 3.07844,2.78985 6,4c2.06586,0.85571 3.38688,1.91761 6,3c1.84776,0.76537 5.2987,-1.05146 7,0c1.90211,1.17557 3.82375,2.48626 6,3c0.97325,0.22975 3.29289,0.29289 4,1c0.70711,0.70711 4,2 9,4c5,2 8,4 11,4c2,0 5,0 7,0c3,0 5,0 7,0c2,0 4,0 7,0c2,0 4,0 8,0c3,0 7,0 10,0c4,0 7,0 12,0c3,0 5,0 6,0c2,0 3,0 5,0c1,0 1.09789,-0.82443 3,-2c0.85065,-0.52573 3.07613,0.38268 4,0c1.30656,-0.5412 0.71022,-2.04291 1,-3c1.04483,-3.45084 2.84723,-5.04132 4,-9c0.88414,-3.03616 1.85194,-5.22836 3,-8c0.5412,-1.30656 1.5405,-2.0535 2,-4c0.51375,-2.17625 2.71413,-4.21167 5,-7c2.68979,-3.28101 4,-6 5,-7c1,-1 2,-2 2,-4c0,-1 0.70711,-2.29289 0,-3c-0.70711,-0.70711 -2.07613,0.38268 -3,0c-1.30656,-0.54119 -2,-1 -4,-1c-3,0 -6.87856,-2.49346 -10,-3c-2.96126,-0.48055 -6.71201,-0.98162 -12,-2c-2.94586,-0.56732 -5,-1 -9,-1c-3,0 -6,-1 -8,-1c-2,0 -5,-3 -7,-3c-2,0 -5.38687,-0.91761 -8,-2c-0.92388,-0.38268 -3.0535,-0.54049 -5,-1c-2.17625,-0.51374 -4.58578,0.41421 -6,-1c-0.70711,-0.70711 -1,-1 -2,-1c-1,0 -2,0 -3,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,0c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-1,0 -3,0 -4,0c-3,0 -5,0 -7,0c-2,0 -4,0 -6,0c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-2,0 -4,0 -5,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,1l-1,0" id="svg_1" stroke- stroke="#000000" fill="none"/>
</g>
</svg>
【问题讨论】：
可能重复：***.com/questions/13408144/simple-path-transition 另一个类似的问题：***.com/questions/5924238/… 【参考方案1】：此答案中列出了三种技术：
有一个全 SVG 解决方案，它涉及逐步修改 stroke-dasharray 的形状以绘制越来越长的“破折号”，然后是巨大的间隙。
演示：http://phrogz.net/svg/progressively-drawing-svg-path-via-dasharray.html
相关代码：
var distancePerPoint = 1;
var drawFPS = 60;
var orig = document.querySelector('path'), length, timer;
orig.addEventListener('mouseover',startDrawingPath,false);
orig.addEventListener('mouseout', stopDrawingPath, false);
function startDrawingPath()
length = 0;
orig.style.stroke = '#f60';
timer = setInterval(increaseLength,1000/drawFPS);
function increaseLength()
var pathLength = orig.getTotalLength();
length += distancePerPoint;
orig.style.strokeDasharray = [length,pathLength].join(' ');
if (length >= pathLength) clearInterval(timer);
function stopDrawingPath()
clearInterval(timer);
orig.style.stroke = '';
orig.style.strokeDasharray = '';
或者，您仍然可以使用所有 SVG 并选择一次构建 SVG 路径一个命令：
演示：http://phrogz.net/svg/progressively-cloning-svg-path.html
相关代码：
// Assumes 'orig' and dup' are SVG paths
function addNextPathSegment()
var nextIndex = dup.pathSegList.numberOfItems;
if (nextIndex<orig.pathSegList.numberOfItems)
var nextSegment = orig.pathSegList.getItem(nextIndex);
var segmentDup = cloneSVGPathSeg( dup, nextSegment );
dup.pathSegList.appendItem( segmentDup );
function cloneSVGPathSeg( path, seg )
switch(seg.pathSegTypeAsLetter)
case 'M': return path.createSVGPathSegMovetoAbs(seg.x,seg.y); break;
case 'm': return path.createSVGPathSegMovetoRel(seg.x,seg.y); break;
case 'L': return path.createSVGPathSegLinetoAbs(seg.x,seg.y); break;
case 'l': return path.createSVGPathSegLinetoRel(seg.x,seg.y); break;
case 'H': return path.createSVGPathSegLinetoHorizontalAbs(seg.x); break;
case 'h': return path.createSVGPathSegLinetoHorizontalRel(seg.x); break;
case 'V': return path.createSVGPathSegLinetoVerticalAbs(seg.y); break;
case 'v': return path.createSVGPathSegLinetoVerticalRel(seg.y); break;
case 'C': return path.createSVGPathSegCurvetoCubicAbs(seg.x,seg.y,seg.x1,seg.y1,seg.x2,seg.y2); break;
case 'c': return path.createSVGPathSegCurvetoCubicRel(seg.x,seg.y,seg.x1,seg.y1,seg.x2,seg.y2); break;
case 'S': return path.createSVGPathSegCurvetoCubicSmoothAbs(seg.x,seg.y,seg.x2,seg.y2); break;
case 's': return path.createSVGPathSegCurvetoCubicSmoothRel(seg.x,seg.y,seg.x2,seg.y2); break;
case 'Q': return path.createSVGPathSegCurvetoQuadraticAbs(seg.x,seg.y,seg.x1,seg.y1); break;
case 'q': return path.createSVGPathSegCurvetoQuadraticRel(seg.x,seg.y,seg.x1,seg.y1); break;
case 'T': return path.createSVGPathSegCurvetoQuadraticSmoothAbs(seg.x,seg.y); break;
case 't': return path.createSVGPathSegCurvetoQuadraticSmoothRel(seg.x,seg.y); break;
case 'A': return path.createSVGPathSegArcAbs(seg.x,seg.y,seg.r1,seg.r2,seg.angle,seg.largeArcFlag,seg.sweepFlag); break;
case 'a': return path.createSVGPathSegArcRel(seg.x,seg.y,seg.r1,seg.r2,seg.angle,seg.largeArcFlag,seg.sweepFlag); break;
case 'z':
case 'Z': return path.createSVGPathSegClosePath(); break;
最后，您可以选择通过定期采样 SVG 路径并绘制到画布来将路径绘制到 HTML5 画布。 （请注意，发生这种情况不需要显示 SVG 路径；您可以完全在 javascript 中构建一个 SVG 路径元素并对其进行采样）：
演示：http://phrogz.net/svg/progressively-drawing-svg-path.html
相关代码：
function startDrawingPath()
points = [];
timer = setInterval(buildPath,1000/drawFPS);
// Assumes that 'orig' is an SVG path
function buildPath()
var nextPoint = points.length * distancePerPoint;
var pathLength = orig.getTotalLength();
if (nextPoint <= pathLength)
points.push(orig.getPointAtLength(nextPoint));
redrawCanvas();
else stopDrawingPath();
function redrawCanvas()
clearCanvas();
ctx.beginPath();
ctx.moveTo(points[0].x,points[0].y);
for (var i=1;i<points.length;i++) ctx.lineTo(points[i].x,points[i].y);
ctx.stroke();
【讨论】：
您需要在 Chrome 和 Firefox 上使用 polyfill 来一次构建一个命令的路径。【参考方案2】：所以有这个类似的问题with this answer。
我选择了你的路径并将其放入该答案的代码中。
jsfiddle demo
HTML：
<html>
<style>
#canvas
border-style:solid;
border-width:1px;
</style>
<div id="canvas">
<p>Hover over me</p>
</div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
Javascript （请注意，示例中使用了 Jquery 1.8.3 和 Raphael 1.5.2）：
$(function()
animateLine = function(canvas, hoverDivName, colorNumber, pathString)
$('#' + hoverDivName).hover(
function()
var line = canvas.path(pathString).attr(
stroke: colorNumber
);
var length = line.getTotalLength();
$('path[fill*="none"]').animate(
'to': 1
,
duration: 5000,
step: function(pos, fx)
var offset = length * fx.pos;
var subpath = line.getSubpath(0, offset);
canvas.clear();
canvas.path(subpath).attr(
'stroke-width': 5,
stroke: colorNumber
);
,
);
, function()
$('path[fill*="none"]').stop(true, false).fadeOut();
);
;
var canvas = Raphael('canvas', 200, 200);
var pathString = "m33,104c1,0 2.1306,-0.8037 23,3c9.07012,1.65314 10,2 24,2c7,0 29,0 33,0c8,0 9,0 11,0c2,0 8,0 11,0c9,0 17,0 18,0c10,0 12,0 20,0c1,0 6,0 7,0c2,0 3.07613,0.38268 4,0c2.61313,-1.08239 2,-3 2,-6c0,-1 0,-2 0,-3c0,-1 0,-2 0,-3c0,-1 0,-2 0,-3c0,-1 0.30745,-3.186 -1,-5c-0.8269,-1.14727 -0.09789,-2.82443 -2,-4c-0.85065,-0.52573 -2.82443,-0.09789 -4,-2c-0.52573,-0.85065 -2.58578,-0.58578 -4,-2c-0.70711,-0.70711 -1.81265,-1.20681 -4,-3c-2.78833,-2.28588 -3.64749,-2.97251 -8,-4c-2.91975,-0.68926 -4.82375,-2.48626 -7,-3c-2.91975,-0.68926 -5.15224,-0.23463 -7,-1c-1.30656,-0.5412 -4.38687,-1.91761 -7,-3c-1.84776,-0.76537 -5.03609,0.37821 -7,0c-5.28799,-1.01837 -8,-3 -9,-3c-2,0 -5.0535,-0.54049 -7,-1c-2.17625,-0.51374 -4.15224,-0.23463 -6,-1c-1.30656,-0.54119 -3,-1 -4,-1c-2,0 -5,-1 -6,-1c-1,0 -3,-2 -6,-2c-2,0 -5,-2 -6,-2c-2,0 -2.02583,-0.67963 -4,-1c-3.12144,-0.50654 -4.15224,-0.23463 -6,-1c-1.30656,-0.54119 -2,-1 -3,-1c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-1,0 -2,0 -3,0c-1,0 -2,0 -3,0c-2,0 -3.85273,0.1731 -5,1c-1.81399,1.30745 -5.18601,1.69255 -7,3c-1.14727,0.8269 -1.82375,2.48626 -4,3c-0.97325,0.22975 -1.69344,1.45881 -3,2c-0.92388,0.38268 -1.45951,1.0535 -1,3c0.51374,2.17625 3.07844,2.78985 6,4c2.06586,0.85571 3.38688,1.91761 6,3c1.84776,0.76537 5.2987,-1.05146 7,0c1.90211,1.17557 3.82375,2.48626 6,3c0.97325,0.22975 3.29289,0.29289 4,1c0.70711,0.70711 4,2 9,4c5,2 8,4 11,4c2,0 5,0 7,0c3,0 5,0 7,0c2,0 4,0 7,0c2,0 4,0 8,0c3,0 7,0 10,0c4,0 7,0 12,0c3,0 5,0 6,0c2,0 3,0 5,0c1,0 1.09789,-0.82443 3,-2c0.85065,-0.52573 3.07613,0.38268 4,0c1.30656,-0.5412 0.71022,-2.04291 1,-3c1.04483,-3.45084 2.84723,-5.04132 4,-9c0.88414,-3.03616 1.85194,-5.22836 3,-8c0.5412,-1.30656 1.5405,-2.0535 2,-4c0.51375,-2.17625 2.71413,-4.21167 5,-7c2.68979,-3.28101 4,-6 5,-7c1,-1 2,-2 2,-4c0,-1 0.70711,-2.29289 0,-3c-0.70711,-0.70711 -2.07613,0.38268 -3,0c-1.30656,-0.54119 -2,-1 -4,-1c-3,0 -6.87856,-2.49346 -10,-3c-2.96126,-0.48055 -6.71201,-0.98162 -12,-2c-2.94586,-0.56732 -5,-1 -9,-1c-3,0 -6,-1 -8,-1c-2,0 -5,-3 -7,-3c-2,0 -5.38687,-0.91761 -8,-2c-0.92388,-0.38268 -3.0535,-0.54049 -5,-1c-2.17625,-0.51374 -4.58578,0.41421 -6,-1c-0.70711,-0.70711 -1,-1 -2,-1c-1,0 -2,0 -3,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,0c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-1,0 -3,0 -4,0c-3,0 -5,0 -7,0c-2,0 -4,0 -6,0c-2,0 -3,0 -5,0c-1,0 -2,0 -3,0c-2,0 -4,0 -5,0c-1,0 -2,0 -4,0c-1,0 -2,0 -3,1l-1,0";
animateLine(canvas, "canvas", "#000", pathString);
);
d] 属性中获取了您的路径，并将其放入 pathString 变量中。
我还添加了一行来定义 [stroke-width]
我只玩过一次 raphael @，所以我从这个example的页面源中查看了方法。）。
You can find raphael + more info from here.
只是为了好玩，I made my own path...
【讨论】：
我可能晚了位，但是如果我希望动画自动开始（而不是显示“悬停”消息），我必须删除什么？跨度> @BetaDecay 我注释掉了悬停线。 Jsfiddle【参考方案3】：使用 Phrogz 出色的技术，我创建了一个非常基本的 GreenSock 动画，使用 TweenLite 将长度值补间到 getTotalLength() 值。
正如您在演示中所见，将其挂接到补间引擎中可为您提供大量控制，并且只涉及很少的代码。
var orig = document.querySelector('path'), length, timer;
var obj = length:0,
pathLength:orig.getTotalLength();
orig.style.stroke = '#f60';
var t = TweenMax.to(obj, 10, length:obj.pathLength, onUpdate:drawLine, ease:Linear.easeNone)
function drawLine()
orig.style.strokeDasharray = [obj.length,obj.pathLength].join(' ');
updateSlider();
非常感谢 Phrogz 的出色想法和代码。
http://codepen.io/GreenSock/pen/zLiux
【讨论】：
【参考方案4】：我去年做了类似的事情来为画布上的绘图设置动画。这些路径都是带有曲线和线条的 SVG 类型路径，因此您可以直接从 SVG 文件中取出它们并将它们放入 Javascript 数组中。
http://www.ashleysheridan.co.uk/coding/javascript/Animated+Glowing+Line+Drawing+in+Canvas
【讨论】：
+1 是一篇不错的文章和技术，但 -1 因为如果您的网站关闭或您更改了 URL，此答案对未来的用户毫无用处。好的答案应该包含足够的信息来解决没有外部资源的问题。 （但拥有演示代码和站点当然也不错。）以上是关于如何为 svg 路径的渐进式绘制动画？的主要内容，如果未能解决你的问题，请参考以下文章