javascript - 谷歌街景缩放到 Fov

Question

我需要完全按照用户选择的方式保存街景图像(包括 panoID、航向、俯仰和视野)。我有以下代码:

            panorama = new google.maps.StreetViewPanorama(document.getElementById('pano'));
            panorama.addListener('pano_changed', function () {
                $('#panoID').val(panorama.getPano());
            });
            panorama.addListener('pov_changed', function () {
                $('#heading').val(panorama.getPov().heading);
                $('#pitch').val(panorama.getPov().pitch);
                $('#fov').val(panorama.getZoom());
            });

问题是我想将缩放保存为 fov 值 https://developers.google.com/maps/documentation/streetview/intro (看fov可选参数)

fov (default is 90) determines the horizontal field of view of the image. The field of view is expressed in degrees, with a maximum allowed value of 120. When dealing with a fixed-size viewport, as with a Street View image of a set size, field of view in essence represents zoom, with smaller numbers indicating a higher level of zoom.

我找到了一些“转换”信息 https://developers.google.com/maps/documentation/javascript/streetview#TilingPanoramas

但它告诉我们，fov 可以到 180，但是 prev。链接告诉 120 值是最大值。为什么？当然，我可以找到转换比率，但也许存在正常方式(即全景图返回 Fov 而不是缩放)？

此外，在 pov_changed 中捕捉放大似乎不是最好的方法。有时缩放未正确更新

Answer 1

找到了下面这个从缩放到FOV转换的函数:

var k = Math.pow(0.5051, zoom);
var fov = 103.7587 * k;

它有效(几乎完全正确):)

已添加

更精确的结果:

var fov = 180 / Math.pow(2,zoom) 

感谢 trungk18