canvas绘制马路和屏幕

 
<script>
export default {
  data () {
    return {
      road: {
        width: 550,
        height: 200,
        color: "gray"
      },
      screens: [
        { x: 0, y: 0, width: 100, height: 40, text: "屏幕 1: 文字 1" },
        { x: 150, y: 0, width: 100, height: 40, text: "屏幕 2: 文字 2" },
        { x: 300, y: 0, width: 100, height: 40, text: "屏幕 3: 文字 3" },
        { x: 450, y: 0, width: 100, height: 40, text: "屏幕 4: 文字 4" }
      ],
      textSpeed: 20 // 文字滚动速度
    }
  },
  mounted() {
  this.updateScreen();
  },
  methods: {
     updateScreen() {
      const canvas = this.$refs.roadCanvas;
      const ctx = canvas.getContext("2d");
 
      // 渲染道路
      ctx.fillStyle = this.road.color;
      ctx.fillRect(0, 10, this.road.width, this.road.height);
 
      // 绘制白色斑马线
      ctx.fillStyle = "white";
      const lineWidth = 80; // 斑马线宽度
      const lineHeight = 10; // 斑马线高度
      const gap = 40; // 斑马线间隔
 
      let x = gap;
 
      while (x < canvas.width) {
        ctx.fillRect(x, 60, lineWidth, lineHeight);
        ctx.fillRect(x, 80, lineWidth, lineHeight);
        ctx.fillRect(x, 100, lineWidth, lineHeight);
        x += lineWidth + gap * 2;
      }
 
 
 
      this.screens.forEach(screen => {
        ctx.fillStyle = "black";
        ctx.fillRect(screen.x, screen.y, screen.width, screen.height);
 
        // 在屏幕上绘制滚动文字
        ctx.fillStyle = "white";
        ctx.font = "16px Arial";
 
        // 计算滚动位置
        const scrollPosition = (Date.now() * this.textSpeed / 1000) % (screen.text.length * 16);
        // console.log('123',scrollPosition)
        // 计算截断的位置，确保文字不会溢出屏幕
        const truncatePosition = Math.min(scrollPosition, screen.width);
 
          // 绘制滚动文字，通过截断位置来实现隐藏溢出部分
          ctx.fillText(
            screen.text.slice(0, truncatePosition / 10),
            screen.x + screen.width - truncatePosition,
            screen.y + 30
          );
 
      });
 
      requestAnimationFrame(this.updateScreen);
    },
  }
};
script>
 
<style>
/* Add any custom styles here */
style>