使用JavaScript从matrix3d()中获取3D CSS旋转值

Get 3D CSS rotation value from matrix3d() with JavaScript

本文关键字:3D 获取 CSS 旋转 JavaScript matrix3d 使用      更新时间:2023-09-26

我有一个元素经过3D转换,如下所示:

.foo {
  transform: rotateX(-30deg) rotateY(35deg);
}

现在我想通过javascript获取这些值。很容易获得3D矩阵:

var matrix = $('.foo').css('transform');
// return:
// matrix3d(0.819152, -0.286788, -0.496732, 0, 0, 0.866025, -0.5, 0, 0.573576, 0.409576, 0.709406, 0, 0, 0, 0, 1)

但是,有可能用这个矩阵来计算类似CSS的值-30和35吗?我刚刚找到了2D变换的方法。

好的,明白了!

var _getTransform = function($element) {
    var matrix = $element.css('transform'),
        rotateX = 0,
        rotateY = 0,
        rotateZ = 0;
    if (matrix !== 'none') {
        // do some magic
        var values = matrix.split('(')[1].split(')')[0].split(','),
            pi = Math.PI,
            sinB = parseFloat(values[8]),
            b = Math.round(Math.asin(sinB) * 180 / pi),
            cosB = Math.cos(b * pi / 180),
            matrixVal10 = parseFloat(values[9]),
            a = Math.round(Math.asin(-matrixVal10 / cosB) * 180 / pi),
            matrixVal1 = parseFloat(values[0]),
            c = Math.round(Math.acos(matrixVal1 / cosB) * 180 / pi);
        rotateX = a;
        rotateY = b;
        rotateZ = c;
    }
    return {
        rotateX: rotateX,
        rotateY: rotateY,
        rotateZ: rotateZ
    };
}