SVG路径计算导致所有归零坐标

时间:2014-09-20 22:38:12

标签: jquery svg snap.svg

我正在制作一个脚本,让我在两个或多个具有相同数量值的关键帧之间创建一个简单的svg路径补间(平滑变形动画)。我输入的形状应该将椭圆形状(关键帧[0])变形为语音气泡形状(关键帧[1])。

我遇到的问题是,当我尝试调试时,它告诉我svg元素的值都是0。

<path d="M0, 0, Q0, 0, 0, 0, L0, 0, Q0, 0, 0, 0, L0, 0, Q0, 0, 0, 0, L0, 0, Q0, 0, 0, 0, L0, 0, L0, 0, L0, 0, Z" fill="#ffffff" stroke="#000000"></path>

当控制台向我显示 应具有的值

M-68.39999999999999, -18.787499999999998, Q-72.9, 0, -97.2, -4.5, L-97.2, -258.525, Q-121.5, -263.02500000000003, -116.99999999999999, -281.8125, L68.39999999999999, -281.8125, Q72.9, -300.59999999999997, 97.2, -296.1, L97.2, -42.075, Q121.5, -37.574999999999996, 116.99999999999999, -18.787499999999998, L48.6, -18.787499999999998, L24.3, 18.787499999999998, L0, -18.787499999999998, ZM-70.93333333333334, -19.483333333333334, Q-75.60000000000001, 0, -100.8, -4.666666666666666, L-100.8, -268.09999999999997, Q-126, -272.76666666666665, -121.33333333333333, -292.25, L70.93333333333334, -292.25, Q75.60000000000001, -311.73333333333335, 100.8, -307.06666666666666, L100.8, -43.63333333333333, Q126, -38.96666666666667, 121.33333333333333, -19.483333333333334, L50.4, -19.483333333333334, L25.2, 19.483333333333334, L0, -19.483333333333334, Z 

我的逻辑肯定会出错,但是我不知道为什么这不起作用。

JS:

$(function() {

    var sponsorBubble = function(el, html, cornerRad) {
        this.html = html,
        this.width = el.parent().width(),
        this.height = el.parent().height(),
        this.arrowWidth = el.parent().width()/4,
        this.arrowHeight = el.parent().height()/8,
        this.cornerRad = cornerRad;


        //ENSURE SAME NUMBER OF PATH SEGMENTS IN ALL KEYFRAMES (START TO END)
        this.keypaths = [];

        this.keypaths[0] = [
            "M",
            (this.width/2) - (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "Q",
            (this.width/2) - (this.arrowWidth/2), this.height - this.arrowHeight,
            (this.width/2), this.height - this.arrowHeight,
            "L",
            (this.width/2), this.height - this.arrowHeight,
            "Q",
            (this.width/2) + (this.arrowWidth/2), this.height - this.arrowHeight,
            (this.width/2) + (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "L",
            (this.width/2) + (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "Q",
            (this.width/2) + (this.arrowWidth/2), this.height,
            (this.width/2), this.height,
            "L",
            (this.width/2), this.height,
            "Q",
            (this.width/2) - (this.arrowWidth/2), this.height,
            (this.width/2) - (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "L",
            (this.width/2) - (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "L",
            (this.width/2) - (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "L",
            (this.width/2) - (this.arrowWidth/2), this.height - (this.arrowHeight/2),
            "Z"
        ];

        this.keypaths[1] = [
            "M", //STARTS AT BOTTOM LEFT, GOING CLOCKWISE
            this.cornerRad, this.height-this.arrowHeight,
            "Q",
            0, this.height-this.arrowHeight,
            0, this.height-this.arrowHeight-this.cornerRad,
            "L",
            0, this.cornerRad,
            "Q",
            0,0,
            this.cornerRad, 0,
            "L",
            this.cornerRad+(this.width - (this.cornerRad*2)), 0,
            "Q",
            this.width, 0,
            this.width, this.cornerRad,
            "L",
            this.width, this.cornerRad+(this.height-this.arrowHeight-(this.cornerRad*2)),
            "Q",
            this.width, this.height-this.arrowHeight,
            this.width-this.cornerRad, this.height-this.arrowHeight,
            "L",
            (this.width/2)+(this.arrowWidth/2), this.height-this.arrowHeight,
            "L",
            this.width/2, this.height,
            "L",
            (this.width/2)-(this.arrowWidth/2), this.height-this.arrowHeight, 
            "Z"
        ];


    };

    sponsorBubble.prototype.getFrame = function(frame, total_steps, current_step) {

    if (this.keypaths[frame + 1]) { //IF THERES FRAMES AFTER
        for (var i = 0; i <= this.keypaths[frame].length; i++) {
            //IF IS A LETTER
            if (isNaN(this.keypaths[frame][i])) {
                if (this.newpath && i < this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
                else if (!this.newpath) {
                    this.newpath = this.keypaths[frame][i];
                }
                else if (this.newpath && i == this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
            }

            //IF IS A NUMBER
            else {
                if (this.newpath && i < this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + (((this.keypaths[frame + 1][i] - this.keypaths[frame][i]) / total_steps) * current_step) + ", ";
                }
                else {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
            }
        }
    }

    else { //NO FRAMES AFTER
        for (var i = 0; i <= this.keypaths[frame].length; i++) {
            //IF IS A LETTER
            if (isNaN(this.keypaths[frame][i])) {
                if (this.newpath && i < this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
                else if (!this.newpath) {
                    this.newpath = this.keypaths[frame][i];
                }
                else if (this.newpath && i === this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
            }

            //IF IS A NUMBER
            else {
                if (this.newpath && i < this.keypaths[frame].length - 1) {
                    this.newpath = this.newpath + this.keypaths[frame][i] + ", ";
                }
                else {
                    this.newpath = this.newpath + this.keypaths[frame][i];
                }
            }
        }
    }

        current_step++;

        if (current_step < total_steps) {
                console.log(this.newpath);
            requestAnimationFrame(function() {
                bub.getFrame(frame, total_steps, current_step);
            });
        }
}

snapper = Snap('#svg');
var bub = new sponsorBubble($('#svg'), 'test', 5, 20);
bub.getFrame(0, 30, 0);

var test = snapper.path(bub.newpath);
    test.attr({
        fill: 'white',
        stroke: 'black'
    });
});

HTML:

<!DOCTYPE html>
<html>
    <head>
        <link type="text/css" rel="stylesheet" href="bubble.css" />
        <script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
        <script type="text/javascript" src="snap.svg-min.js"></script>
        <script type="text/javascript" src="bubble.js"></script>
    </head>

    <body>
        <div id="inset">
            <div id="inset2">
                <svg id="svg" width="100%" height="100%"></svg>
            </div>
        </div>
    </body>

</html>

CSS:

body, html {
    width: 100%;
    height: 100%;
    border: 0;
    padding: 0;
    margin: 0;
}

#inset {
 width: 20%;
 height: 50%;
 position: absolute;
 bottom: 0;
 left: 50%;
}

#inset2 {
 width: 80%;
 height: 100%;
}

的jsfiddle: http://jsfiddle.net/bmjkz1rf/

1 个答案:

答案 0 :(得分:1)

您的插值算法错误。

要在两个值x0x1之间进行插值,公式为:

x0 + ((x1 - x0) * current_step / total_steps)

该代码目前缺少第一个x0字词。

我认为还有更多需要解决的问题。就目前而言,this.newpath是一个随着递归的进展而增长和增长的字符串,在“Z”之后和下一个“M”之前没有任何描述。我不确切知道需要什么,但我不认为这是正确的。即使你修复了“... ZM ......”的描绘,你仍然会得到一个怪物字符串,而我想你想要一组(一个数组?)的单个帧。

即使我错了而且你确实需要一个怪物字符串,最好放弃.getFrame()的递归并迭代调用它,在每次迭代时返回一帧的数据,然后构建你在调用函数中的最终数据结构。