demo/transform.html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Transform (Scale) Parent demo</title>

  <link rel="stylesheet" href="demo.css"/>
  <script src="../dist/gridstack-all.js"></script>

</head>
<body>
  <div class="container-fluid">
    <h1>Transform Parent demo</h1>
    <p>example where the grid parent has a translate(50px, 100px) scale(0.5, 0.5) </p>
    <div>
      <a class="btn btn-primary" onClick="addNewWidget()" href="#">Add Widget</a>
      <a class="btn btn-primary" onClick="zoomIn()" href="#">Zoom in</a>
      <a class="btn btn-primary" onClick="zoomOut()" href="#">Zoom out</a>
    </div>
    <br><br>
    <div style="transform: translate(50px, 100px) scale(var(--global-scale), var(--global-scale)); transform-origin: 0 0;">
      <div class="grid-stack"></div>
    </div>
  </div>
  <script src="events.js"></script>
  <script type="text/javascript">
    let scale = 0.5;

    let grid = GridStack.init({float: true});
    addEvents(grid);

    let items = [
      {x: 0, y: 0, w: 2, h: 2},
      {x: 2, y: 0, w: 1},
      {x: 3, y: 0, h: 1},
      {x: 0, y: 2, w: 2},
    ];
    let count = 0;

    getNode = function() {
      let n = items[count] || {
        x: Math.round(12 * Math.random()),
        y: Math.round(5 * Math.random()),
        w: Math.round(1 + 3 * Math.random()),
        h: Math.round(1 + 3 * Math.random())
      };
      n.content = n.content || String(count);
      count++;
      return n;
    };

    addNewWidget = function() {
      let w = grid.addWidget(getNode());
    };

    const updateScaleCssVariable = () => {
      document.body.style.setProperty('--global-scale', `${scale}`);
    }

    zoomIn = function() {
      const scaleStep = scale < 1 ? 0.05 : 0.1;
      scale += scaleStep;
      updateScaleCssVariable();
    }

    zoomOut = function() {
      const scaleStep = scale < 1 ? 0.05 : 0.1;
      scale -= scaleStep;
      updateScaleCssVariable();
    }

    updateScaleCssVariable();


    addNewWidget();
    addNewWidget();
    addNewWidget();
  </script>
</body>
</html>