如何从 Polygon 动态更新 SVG viewBox 值

Question

我创建了漫画书页面面板的 SVG 地图。

<svg id="svg1413"  class="svg-pg" width="100%" height="100%" version="1.1" viewBox="0 0 178 254" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" style="transition: .6s ease-out;">
    <image id="image1966" width="178" height="254" clip-path="url('#SvgjsClipPath1413')" xlink:href="https://i.imgur.com/yiZFUK4.jpg" />
    <g id="SvgjsG1413" clip-path="url('#SvgjsClipPath1413')" class="click-panels">
        <polygon fill="transparent" points=" 12,13 88,13 88,49 12,49"></polygon>
        <polygon fill="transparent" points=" 81,44 166,44 166,74 81,74"></polygon>
        <polygon fill="transparent" points=" 12,13 166,13 166,75 12,75"></polygon>
        <polygon fill="transparent" points=" 101,80 166,80 166,118 101,118"></polygon>
        <polygon fill="transparent" points=" 12,80 166,80 166,147 12,147"></polygon>
        <polygon fill="transparent" points=" 12,152 91,152 91,200 12,200"></polygon>
        <polygon fill="transparent" points=" 73,171 155,171 155,209 73,209"></polygon>
        <polygon fill="transparent" points=" 12,198 79,198 79,235 12,235"></polygon>
        <polygon fill="transparent" points=" 12,152 166,152 166,235 12,235"></polygon>
    </g>
    <defs id="SvgjsDefs1413">
        <clipPath id="SvgjsClipPath1413">
            <rect id="SvgjsRect1413" width="100%" height="100%" x="0" y="0">
            </rect>
        </clipPath>
    </defs>     
</svg>
<svg>
    ...svg content
</svg>
<svg>
    ...svg content
</svg>

我想要实现的是：

• 遍历所有
• 在
• 每个 包含 4 对坐标（例如points=" x1,y1 x2,y2 x3,y3 x4,y4"）
• 我希望用循环中当前 点的值更新父 viewBox 值和 X 和 Y 值。

我已经想出了如何计算这些值，但我不知道如何在 Javascript 中实现这一点。

我的计算 viewBox 值的伪代码

if <svg viewBox=" a b c d ">
a = x1, b = y1, c = x2 - x1, d = y3 - y2

更新 值

if <rect x="e" y="f">
e = x1, f = y1

更新：如何通过点击/滑动事件控制转换而不是使其自动转换？

<div id="controls" class="ctl-btn" style="width: 100%; position: absolute; bottom: 0; margin: 0 -8px; background-color: rgba(6,6,6,0.40);">
    <div style="max-width: 800px; text-align: center; margin: 0 auto;">
        <button class="pg-ctl-bk" style="margin: 8px; padding: 8px 10px;">  Back </button>
        <button class="pg-ctl-nxt" style="margin: 8px; padding: 8px 10px;"> Next  </button>
    </div>
</div>

Answer 1

我不知道你为什么在这里使用 元素，而你只需要一个 javascript Array/JSON，或者最终是至少具有 x、y、width 和 @ 的 元素viewBox 属性请求的 987654325@ 属性，但是好吧...让我们处理 s 然后...

要将 的point 属性值转换为viewBox 属性，最简单的方法是调用polygonElement.getBBox()，它将返回一个带有所需值的SVGRect。

要为viewBox 属性设置动画，最简单的可能是使用SMIL 动画，以及用于MS 浏览器的polyfill。

您只需定义一个以viewBox 属性为目标的<animate> 元素，并将其to 属性更新为目标值，然后将其from 属性更新为当前值。

// animate : <animate attributeName="viewBox" ...>
// rect : {SVGRect} result of polygonElement.getBBox();
function animateViewBox(animate, rect) {
  animate.setAttribute('from', animate.getAttribute('to'));
  animate.setAttribute('to', `${rect.x} ${rect.y} ${rect.width} ${rect.height}`);
  animate.beginElement(); // (re)start the animation
}

一旦有了这个，我们只需要设置一个函数来遍历 svg 中的所有 元素。

function animateViewBox(animate, rect) {
  animate.setAttribute('from', animate.getAttribute('to'));
  animate.setAttribute('to', `${rect.x} ${rect.y} ${rect.width} ${rect.height}`);
  animate.beginElement(); // (re)start the animation
}

// container
const svg = document.getElementById('svg1413');
// all the <polygons> coordinates (would be better as JSON...)
const polygons = svg.querySelectorAll('polygon');
// <animate> element
const animator = svg.querySelector('.viewBoxAnimator');

// our iterator, we could call it on click
let i = 0;

function iterate() {
  if (i < polygons.length) {
    animateViewBox(animator, polygons[i++].getBBox());
    return true;
  }
}

// but we'll automate it
(async() => {
  while (iterate()) {
    await wait(1500);
  }
})();


function wait(time) {
  return new Promise(res => setTimeout(res, time));
}

svg {
  width: 100%;
  height: 100%;
  max-width: 100vw;
  max-height: 100vh;
  transition: all .6s;
}

html {
  background: black;
}

<!-- SMIL for IE -->
<script src="https://cdn.jsdelivr.net/gh/Kaiido/FakeSmile@1e50d675df616a8e784e0e6e931b3f0d595367d4/smil.user.js"></script>

<svg id="svg1413" class="svg-pg" width="154" height="83" version="1.1" viewBox="0 0 178 254" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <animate class="viewBoxAnimator" attributeType="XML" attributeName="viewBox" from="0 0 178 254" to="0 0 178 254" dur="0.6s" fill="freeze"/>
  <image id="image1966" width="178" height="254" xlink:href="https://i.imgur.com/yiZFUK4.jpg" />
  <g id="SvgjsG1413" class="click-panels">
    <polygon fill="transparent" points=" 12,13 88,13 88,49 12,49"></polygon>
    <polygon fill="transparent" points=" 81,44 166,44 166,74 81,74"></polygon>
    <polygon fill="transparent" points=" 12,13 166,13 166,75 12,75"></polygon>
    <polygon fill="transparent" points=" 101,80 166,80 166,118 101,118"></polygon>
    <polygon fill="transparent" points=" 12,80 166,80 166,147 12,147"></polygon>
    <polygon fill="transparent" points=" 12,152 91,152 91,200 12,200"></polygon>
    <polygon fill="transparent" points=" 73,171 155,171 155,209 73,209"></polygon>
    <polygon fill="transparent" points=" 12,198 79,198 79,235 12,235"></polygon>
    <polygon fill="transparent" points=" 12,152 166,152 166,235 12,235"></polygon>
  </g>
</svg>

Answer 2

你使用了 svg.js 标签，所以你得到一个 svg.js 答案：

// Reference to svg
const canvas = SVG('#svg1413')

// List of all polygons
const polygons = canvas.find('#SvgjsG1413 polygon')

// List of all bboxes
const boxes = polygons.bbox()

const nextImage = function (index) {
  // Animate viewbox over 1s to new box
  canvas.animate(1000).viewbox(boxes[index])

  // Next image in 2s
  setTimeout(() => nextImage(++index), 2000)
}

nextImage(0)

svg {
  width: 100%;
  height: 100%;
  max-width: 100vw;
  max-height: 100vh;
}

html {
  background: black;
}

<script src="https://cdn.jsdelivr.net/npm/@svgdotjs/svg.js@latest/dist/svg.min.js"></script>


<svg id="svg1413"  class="svg-pg" width="154" height="254" version="1.1" viewBox="0 0 178 254" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" style="transition: .6s ease-out;">
    <image id="image1966" width="178" height="254" clip-path="url('#SvgjsClipPath1413')" xlink:href="https://i.imgur.com/yiZFUK4.jpg" />
    <g id="SvgjsG1413" clip-path="url('#SvgjsClipPath1413')" class="click-panels">
        <polygon fill="transparent" points=" 12,13 88,13 88,49 12,49"></polygon>
        <polygon fill="transparent" points=" 81,44 166,44 166,74 81,74"></polygon>
        <polygon fill="transparent" points=" 12,13 166,13 166,75 12,75"></polygon>
        <polygon fill="transparent" points=" 101,80 166,80 166,118 101,118"></polygon>
        <polygon fill="transparent" points=" 12,80 166,80 166,147 12,147"></polygon>
        <polygon fill="transparent" points=" 12,152 91,152 91,200 12,200"></polygon>
        <polygon fill="transparent" points=" 73,171 155,171 155,209 73,209"></polygon>
        <polygon fill="transparent" points=" 12,198 79,198 79,235 12,235"></polygon>
        <polygon fill="transparent" points=" 12,152 166,152 166,235 12,235"></polygon>
    </g>  
</svg>