tourism-wxapp/node_modules/swiper/modules/effect-flip/effect-flip.js

import createShadow from '../../shared/create-shadow.js';
import effectInit from '../../shared/effect-init.js';
import effectTarget from '../../shared/effect-target.js';
import effectVirtualTransitionEnd from '../../shared/effect-virtual-transition-end.js';
export default function EffectFlip({
  swiper,
  extendParams,
  on
}) {
  extendParams({
    flipEffect: {
      slideShadows: true,
      limitRotation: true,
      transformEl: null
    }
  });

  const setTranslate = () => {
    const {
      slides,
      rtlTranslate: rtl
    } = swiper;
    const params = swiper.params.flipEffect;

    for (let i = 0; i < slides.length; i += 1) {
      const $slideEl = slides.eq(i);
      let progress = $slideEl[0].progress;

      if (swiper.params.flipEffect.limitRotation) {
        progress = Math.max(Math.min($slideEl[0].progress, 1), -1);
      }

      const offset = $slideEl[0].swiperSlideOffset;
      const rotate = -180 * progress;
      let rotateY = rotate;
      let rotateX = 0;
      let tx = swiper.params.cssMode ? -offset - swiper.translate : -offset;
      let ty = 0;

      if (!swiper.isHorizontal()) {
        ty = tx;
        tx = 0;
        rotateX = -rotateY;
        rotateY = 0;
      } else if (rtl) {
        rotateY = -rotateY;
      }

      $slideEl[0].style.zIndex = -Math.abs(Math.round(progress)) + slides.length;

      if (params.slideShadows) {
        // Set shadows
        let shadowBefore = swiper.isHorizontal() ? $slideEl.find('.swiper-slide-shadow-left') : $slideEl.find('.swiper-slide-shadow-top');
        let shadowAfter = swiper.isHorizontal() ? $slideEl.find('.swiper-slide-shadow-right') : $slideEl.find('.swiper-slide-shadow-bottom');

        if (shadowBefore.length === 0) {
          shadowBefore = createShadow(params, $slideEl, swiper.isHorizontal() ? 'left' : 'top');
        }

        if (shadowAfter.length === 0) {
          shadowAfter = createShadow(params, $slideEl, swiper.isHorizontal() ? 'right' : 'bottom');
        }

        if (shadowBefore.length) shadowBefore[0].style.opacity = Math.max(-progress, 0);
        if (shadowAfter.length) shadowAfter[0].style.opacity = Math.max(progress, 0);
      }

      const transform = `translate3d(${tx}px, ${ty}px, 0px) rotateX(${rotateX}deg) rotateY(${rotateY}deg)`;
      const $targetEl = effectTarget(params, $slideEl);
      $targetEl.transform(transform);
    }
  };

  const setTransition = duration => {
    const {
      transformEl
    } = swiper.params.flipEffect;
    const $transitionElements = transformEl ? swiper.slides.find(transformEl) : swiper.slides;
    $transitionElements.transition(duration).find('.swiper-slide-shadow-top, .swiper-slide-shadow-right, .swiper-slide-shadow-bottom, .swiper-slide-shadow-left').transition(duration);
    effectVirtualTransitionEnd({
      swiper,
      duration,
      transformEl
    });
  };

  effectInit({
    effect: 'flip',
    swiper,
    on,
    setTranslate,
    setTransition,
    perspective: () => true,
    overwriteParams: () => ({
      slidesPerView: 1,
      slidesPerGroup: 1,
      watchSlidesProgress: true,
      spaceBetween: 0,
      virtualTranslate: !swiper.params.cssMode
    })
  });
}