Swing效果jQuery动画背景

我正在为一个网页制作一个自动设置动画的背景摆动，我不知道当背景回到原点时如何解决这个问题

这是我在其他一些网站上所做的代码：

function scrollbackground() {
        // decrease the offset by 1, or if its less than 1 increase it by the background height minus 1
//          offset = (offset < 1) ? offset + (backgroundheight - 1) : offset - 1;
        offset = offset - 1;
        // apply the background position
        $('body').css("background-position", "50% " + offset + "px");
        // call self to continue animation
        setTimeout(function() {
            scrollbackground();
            }, 1000
        );
    }

---

这对于向一个方向移动非常有效。我想要的是，当背景到达特定偏移量时，将其恢复为0。

您可以将其作为参数发送

function scrollbackground(limit) {
        // decrease the offset by 1, or if its less than 1 increase it by the background height minus 1
//          offset = (offset < 1) ? offset + (backgroundheight - 1) : offset - 1;
        offset = offset<limit?offset - 1:offset + 1;
        // apply the background position
        $('body').css("background-position", "50% " + offset + "px");
        // call self to continue animation
        setTimeout(function() {
            scrollbackground(limit);
            }, 1000
        );
    }

试试这个

var backgroundImageWidth;
var moveLeft = true;
var offset = 0;
    function scrollbackground() {

offset = moveLeft?offset-1:offset+1;
if(offset*-1 == backgroundImageWidth)
   moveLeft = false;
else if(offset == 0)
   moveLeft = true;

            // apply the background position
            $('body').css("background-position", "50% " + offset + "px");
            // call self to continue animation
            setTimeout(function() {
                scrollbackground();
                }, 1000
            );
        }