jquery - mouseMove 上的水平滚动 - 较小 div 中的宽 div 并溢出 :hidden (Can't get the math to work)

Question

我正在尝试制作一条图像拇指的“线”，它在鼠标移动时滚动。我让它工作了，但我现在的问题是我想在侧面做一个“填充”，这样我就不必将鼠标一直拉到侧面才能看到第一个/最后一个拇指。但我真的无法让它工作:/

这是我现在的脚本:

// MouseMove scrolling on thumbs
var box = $('.thumbs-block'),
    innerBox = $('.thumbs'),
    lastElement = innerBox.find('a:last-child');

var offsetPx = 100;
var boxOffset = box.offset().left;

var boxWidth = box.width() /* - (offsetPx*2)*/;
var innerBoxWidth = (lastElement[0].offsetLeft + lastElement.outerWidth(true)) - boxOffset /* + (offsetPx*2)*/;

scrollDelayTimer = null;
box.mousemove(function (e) {
    console.log('boxWidth: ' + boxWidth + '   innerBoxWidth: ' + innerBoxWidth + '   box.scrollLeft(): ' + box.scrollLeft());

    var mouseX = e.pageX;
    var boxMouseX = mouseX - boxOffset;

    if ((boxMouseX > offsetPx) && (boxMouseX < (boxWidth - offsetPx))) {
        var left = (boxMouseX * (innerBoxWidth - boxWidth) / boxWidth) /* - offsetPx*/;

        clearTimeout(scrollDelayTimer);
        scrollDelayTimer = setTimeout(function () {
            scrollDelayTimer = null;
            box.stop().animate({
                "scrollLeft": left
            }, {
                queue: false,
                duration: 500,
                easing: 'linear'
            });
        }, 10);
    }
});

我在一些地方尝试添加偏移量(内联注释掉)，其中一些可以在一端工作，但在另一端则不行:/

我很确定这是数学问题，但我不知道我应该做什么:/

这是一个 jsFiddle:http://jsfiddle.net/6CJfs/1/

我希望我的问题足够清楚，不知道如何解释它，并希望有人可以帮助:)

Answer 1

你的脚本不流畅，所以我完全修改了它(抱歉:)
用一个非常简单的方法:

$(function() {

  const $bl = $(".thumbs-block"),
    $th = $(".thumbs"),
    blW = $bl.outerWidth(),
    blSW = $bl.prop("scrollWidth"),
    wDiff = (blSW / blW) - 1, // widths difference ratio
    mPadd = 60, // Mousemove Padding
    damp = 20; // Mousemove response softness

  let posX = 0,
    mX2 = 0, // Modified mouse position
    mmAA = blW - (mPadd * 2), // The mousemove available area
    mmAAr = (blW / mmAA), // get available mousemove fidderence ratio
    itv = null;

  const anim = () => {
    posX += (mX2 - posX) / damp; // zeno's paradox equation "catching delay"    
    $th.css({
      transform: `translateX(${-posX * wDiff}px)`
    });
  };

  $bl.on("mousemove", function(e) {
    const mouseX = e.pageX - $(this).prop("offsetLeft");
    mX2 = Math.min(Math.max(0, mouseX - mPadd), mmAA) * mmAAr;
  }).on("mouseenter", function(e) {
    itv = setInterval(anim, 10);
  }).on("mouseleave", function() {
    clearInterval(itv);
  });

});

.thumbs-block {
  position: relative;
  overflow: hidden;
  max-width: 100%;
}

.thumbs-block .thumbs {
  display: flex;
  flex-flow: row nowrap;
}

<div class="thumbs-block">
  <div class="thumbs">
    <a class="thumb"><img src="http://placehold.it/120x120/0bf&text=01" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/f0b&text=02" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/bf0&text=03" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/b0f&text=04" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/fb0&text=05" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/0fb&text=06" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/0bf&text=07" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/f0b&text=08" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/bf0&text=09" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/b0f&text=10" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/fb0&text=11" /></a>
    <a class="thumb"><img src="http://placehold.it/120x120/0fb&text=12" /></a>
  </div>
</div>

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