8

有谁知道如何将文本附加到 Raphaël 中的路径?类似http://www.w3.org/TR/SVG11/images/text/toap02.svg 我知道 jQuery SVG 可以做到这一点,但我找不到使用 Raphaël js 的简单方法。我想将此文本附加到贝塞尔曲线并移动它。

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3 回答 3

12

有两种方法可以做到这一点。

  1. 更简单的方法是使用拉斐尔.print()方法。这可以将文本转换为路径。每个角色都有自己的路径。然后您可以遍历每个字符并使用.translate()and适当地移动和旋转它.angle()

  2. 更难的方法是为Raphael 的SVGVML.text()实现路径上的文本。

这是方法 1 的快速粗略开始,不使用.print()旋转字体

window.onload = function() {
    var i, newP,
        R = Raphael("canvas",500,400),

          // Create our set of letter paths
        t = R.print(100, 0, "this is a test", R.getFont("whoa"), 30),

          // Create the path to follow
        p = R.path("M 50 100 C 100 50 150 0 200 50 C 250 100 300 150 350 100" +
                   " C 400 50 450 50 450 50").attr("stroke", "none"),
        pLen = p.getTotalLength(), // Length of path to follow
        tLen = t.length,           // Number of characters
        oneL = pLen/tLen;          // Average length of 1 character
          // You can also use .getBBox() for each character instead       

      // Position each character
    for (i = 0; i < tLen; i++) {

          // Get x,y of the path to follow
        newP = p.getPointAtLength(i * oneL);

          // Move the letter
        t[i].translate((i * oneL)-newP.x, newP.y); 
        t[i].attr("fill", Raphael.getColor());
    }
};​

用这个 jsFiddle 试试

注意:上面的代码非常粗糙并且有一些重要的定位问题,但我认为一般的方法是使用 Raphael 将文本放在路径上。

于 2010-10-14T18:56:38.000 回答
6

raphael 2.1 print() 函数不再返回一组路径,而是返回包含所有字母的单个路径。所以这里的所有解决方案都不适用于 raphael 2.1(当前版本)。我开发了以下小插件,将 printLetters() 方法添加到纸上,单独打印字母并返回一个集合,就像旧的 print() 方法一样。此外,该插件支持将此文本与路径对齐。例如,要使用插件对齐路径上的文本,您只需执行以下操作:

var r = Raphael(0, 0, 500, 500);
var path1 = "M 50 100 C 100 50 150 0 200 50" +
    " C 250 100 300 150 350 100" +
    " C 400 50 450 50 450 50";
var text1 = r.printLetters(20, 150, "habia una vez una vaca",
        r.getFont("my underwood"), 30, null, null, path1).attr({
    fill : "red",
    stroke : "black"
});

插件代码是:

(function() {
    /**
     * do the job of putting all letters in a set returned bu printLetters in a path
     * @param p - can be a rpahael path obejct or string
     */
    var _printOnPath = function(text, paper, p) {
        if(typeof(p)=="string")
            p = paper.path(p).attr({stroke: "none"});
        for ( var i = 0; i < text.length; i++) {       
            var letter = text[i];
            var newP = p.getPointAtLength(letter.getBBox().x);
            var newTransformation = letter.transform()+
                 "T"+(newP.x-letter.getBBox().x)+","+
                (newP.y-letter.getBBox().y-letter.getBBox().height);       
            //also rotate the letter to correspond the path angle of derivative
            newTransformation+="R"+
                (newP.alpha<360 ? 180+newP.alpha : newP.alpha);
            letter.transform(newTransformation);
        }
    };

    /** print letter by letter, and return the set of letters (paths), just like the old raphael print() method did. */
    Raphael.fn.printLetters = function(x, y, str, font, size,
            letter_spacing, line_height, onpath) {
        letter_spacing=letter_spacing||size/1.5;
        line_height=line_height||size;
        this.setStart();
        var x_=x, y_=y;
        for ( var i = 0; i < str.length; i++) {
            if(str.charAt(i)!='\n') {
                var letter = this.print(x_,y_,str.charAt(i),font,size);
                x_+=letter_spacing;               
            }
            else {
                x_=x;
                y_+=line_height;
            }
        }
        var set = this.setFinish();
        if(onpath) {
            _printOnPath(set, this, onpath);
        }
        return set;
    };   
})();
于 2012-03-29T17:47:03.913 回答
0

这是基于raphael4gwt (java) 的代码,但我认为 javascript 程序员可以轻松适应它。它基于拉斐尔 2.0。它类似于上面的解决方案,但更好。它使用转换字符串来绝对定位和旋转每个字母以将其放置在路径上:

/* make some text follow a path */
Font anchorFont = paper.getFont("Anchor Steam NF");
Set text1 = paper.print(120,330,"a text that follows a path", anchorFont, 40);

//the path where we want to place the text
Path p = paper.path(
    "M 50 100 C 100 50 150 0 200 50" +
" C 250 100 300 150 350 100" +
" C 400 50 450 50 450 50");
p.attr(Attrs.create().stroke("none"));//hide the path

/* for each letter, we add an absolute translation to its 
 * transformation string and also add an absolute rotation 
 * to correspond to path angle of derivative. */
for(int i = 0; i<text1.size(); i++) {
    Shape letter = text1.item(i);

    //get the point of a letter on the path
    Point newP = p.getPointAtLength(letter.getBBox().getX());

    String newTransformation = letter.getTransform()+                   
        "T"+(newP.getX()-letter.getBBox().getX())+","+
        (newP.getY()-letter.getBBox().getY()-letter.getBBox().getHeight());

    //also rotate the letter to correspond the path angle of derivative
    newTransformation+="R"+
        (newP.getAlpha()<360 ? 180+newP.getAlpha() : newP.getAlpha());

    letter.setTransform(newTransformation);         
}
于 2012-03-02T14:34:56.787 回答