wheel-de-scroll.user.js

// ==UserScript==
// @name        wheel de slide
// @namespace   http://rikuba.com/
// @include     http://www.slideshare.net/*
// @include     https://www.slideshare.net/*
// @include     http://speakerdeck.com/player/*
// @include     https://speakerdeck.com/player/*
// @include     http://slides.com/*
// @include     http://qiita.com/*
// @include     http://niconare.nicovideo.jp/watch/*
// @include     http://azu.github.io/slide-pdf.js/*
// @version     1.3
// @grant       GM_log
// ==/UserScript==

const siteinfoList = [
  // embedded slideshare
  {
    url: /^https?:\/\/www\.slideshare\.net\/slideshow\//,
    target: '#player',
    prev: '#btnPrevious',
    next: '#btnNext',
  },
  {
    url: /^https?:\/\/www\.slideshare\.net\/[^/]+\/[^/]+/,
    target: '#svPlayerId',
    prev: '#btnPrevious',
    next: '#btnNext',
  },
  {
    url: /^https?:\/\/speakerdeck\.com\/player\//,
    target: '#player',
    prev: '.prev',
    next: '.next',
  },
  {
    url: /http:\/\/slides\.com\//,
    target: '.reveal',
    prev: '.navigate-left',
    next: '.navigate-right',
  },
  {
    url: /^http:\/\/qiita\.com\/[^/]+/,
    target: '*[data-react-class="T.SlideContainer"]',
    prev: '.slide_controller_btnGroup > .slide_controller_btn:first-child',
    next: '.slide_controller_btnGroup > .slide_controller_btn:last-child',
  },
  {
    url: /^http:\/\/niconare\.nicovideo\.jp\/watch\//,
    target: '#main-box',
    prev: '#page-previous',
    next: '#page-next',
  },
  //
  {
    url: /^http:\/\/azu\.github\.io\/slide-pdf\.js\//,
    target: ':root',
    prev: '#js-prev',
    next: '#js-next',
  },
];

for (let siteinfo of siteinfoList) {
  if (siteinfo.url.test(location.href)) {
    const target = document.querySelector(siteinfo.target);
    if (target) {
      target.addEventListener('wheel', createWheelHandler(siteinfo));
      break;
    }
    GM_log('target element not found');
  }
}

function createWheelHandler(siteinfo) {
  let elements = {
    prev: null,
    next: null,
  };
  return function handleWheel(e) {
    if (e.deltaY < 0) {
      clickElement(e, 'prev');
    } else if (e.deltaY > 0) {
      clickElement(e, 'next');
    }
  };
  function clickElement(e, key) {
    if (!elements[key]) {
      elements[key] = e.currentTarget.querySelector(siteinfo[key]);
      if (!elements[key]) {
        GM_log(`${key} element not found`);
        return;
      }
    }
    e.preventDefault();
    elements[key].click();
  }
}