city-gather/src/subPack-film/choose-seat/components/pages/canvasOperator.js

export default class CanvasOperator {
  constructor(canvas) {
    this.canvas = canvas
  }

  /* ---------- RAF 封装 ---------- */
  raf(cb) {
    if (typeof this.canvas.requestAnimationFrame === 'function') {
      return this.canvas.requestAnimationFrame(cb)
    }
    if (typeof requestAnimationFrame === 'function') {
      return requestAnimationFrame(cb)
    }
    return setTimeout(cb, 16)
  }

  cancelRaf(id) {
    if (typeof this.canvas.cancelAnimationFrame === 'function') {
      return this.canvas.cancelAnimationFrame(id)
    }
    if (typeof cancelAnimationFrame === 'function') {
      return cancelAnimationFrame(id)
    }
    return clearTimeout(id)
  }

  /* ---------- 图片加载 ---------- */
  async loadImage(filePath) {
    let img
    if (typeof this.canvas.createImage === 'function') {
      img = this.canvas.createImage()
    }
    if (typeof Image !== 'undefined') {
      img = new Image()
    }
    // #ifndef H5
    img.crossOrigin = 'anonymous'
    // #endif
    return new Promise((resolve, reject) => {
      img.src = filePath
      img.onload = () => resolve(img)
      img.onerror = () => {
        console.error('[loadImage] 图片加载失败:', filePath, '请检查图片路径')
        reject(new Error('图片加载失败'))
      }
    })
  }
}