Question

X3DOM是否有正确的方法来实现自定义相机导航？我想在用户拖动缩放滑块时进行缩放，并在用户拖动屏幕时进行平移。 X3DOM是否有用于调用pan（），zoom（）或rotate（）函数的API？

到目前为止，我可以想到三种解决方法，这些解决方案并不理想：

手动更改视点属性：

document.getElementById("the_viewpoint").setAttribute("orientation", "some numbers here");
保持视点固定并更改<transform>的位置/旋转，其中包含整个3D世界
重新路由事件。例如，当用户滑动缩放滑块时，触发鼠标滚轮事件进行缩放。

Answer 1

看起来像this functionality was added fairly recently，但是has yet to be properly documented

PR包括这个例子：

var d = function(selector) { return document.querySelector(selector)}

x3dom.runtime.ready = function() {
    var x3d = d('x3d');
    var viewpoint = d('viewpoint');
    var x3dCanvas = x3d.runtime.canvas;

    var _onMouseWheel = x3dCanvas.onMouseWheel;

    x3dCanvas.onMouseWheel = function(event) {
        if(event.altKey) {
            var offset = .01
            var fov = parseFloat(viewpoint.getAttribute('fieldofview')) || 1.571;

            if(event.wheelDelta < 0) offset = -offset;
            fov = Math.min(2, Math.max(0, fov+offset));

            viewpoint.setAttribute('fieldofview', fov)

        } else {
            _onMouseWheel.call(this, event);
        }
    }

    x3dCanvas.canvas.removeEventListener('mousewheel', _onMouseWheel); // unable to unbind when handler is anonymous function 
    x3dCanvas.canvas.addEventListener('mousewheel', x3dCanvas.onMouseWheel);
}

X3DOM自定义导航

1 个答案: