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			137 lines
		
	
	
		
			5.1 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			137 lines
		
	
	
		
			5.1 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
<!--********************************************************************
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* by 优雅永不过时 https://github.com/z2586300277
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*********************************************************************-->
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<!DOCTYPE html>
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<html>
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<head>
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    <meta charset="UTF-8" />
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    <style>
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        * {
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            margin: 0;
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            padding: 0;
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            overflow: hidden;
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        }
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        body,
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        #box {
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            width: 100%;
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            background-color: #1f1f1f;
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            height: 100%;
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        }
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    </style>
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</head>
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<body>
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    <div id="box"></div>
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    <script type="importmap">
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        {
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            "imports": {
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                "three": "./../../three/build/three.module.js",
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                "three/addons/": "./../../three/examples/jsm/",
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                "three/example/": "./../../three/examples/"
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            }
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        }
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    </script>
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    <script type="module">
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        import * as THREE from "three";
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        import { OrbitControls } from "three/addons/controls/OrbitControls.js";
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        const box = document.getElementById('box')
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        const scene = new THREE.Scene()
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        const camera = new THREE.PerspectiveCamera(75, box.clientWidth / box.clientHeight, 0.1, 1000)
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        camera.position.set(0, 10, 10)
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        const renderer = new THREE.WebGLRenderer()
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        renderer.setSize(box.clientWidth, box.clientHeight)
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        box.appendChild(renderer.domElement)
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        new OrbitControls(camera, renderer.domElement)
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        scene.add(new THREE.AmbientLight(0xffffff, 3), new THREE.AxesHelper(1000))
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        animate()
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        function animate() {
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            requestAnimationFrame(animate)
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            renderer.render(scene, camera)
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        }
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        window.onresize = () => {
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            renderer.setSize(box.clientWidth, box.clientHeight)
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            camera.aspect = box.clientWidth / box.clientHeight
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            camera.updateProjectionMatrix()
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        }
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        const citys = await fetch('./city.json').then(res => res.json()) // 获取城市数据
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        const updateCanvasText = createCanvasText({ dpr: 1.4 }) // 创建canvas
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        const getColor = () => '#' + Math.floor(Math.random() * 0xffffff).toString(16).padStart(6, '0') // 随机颜色
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        for (const key in citys) {
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            const canvas = updateCanvasText({ text: key, color: getColor() })
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            const texture = new THREE.TextureLoader().load(canvas.toDataURL())
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            const material = new THREE.SpriteMaterial({ map: texture })
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            const sprite = new THREE.Sprite(material)
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            sprite.scale.set(canvas.width / canvas.height, 1, 1)
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            // 设置随机位置
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            sprite.position.set(
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                Math.random() * 20 - 10,
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                Math.random() * 20 - 10,
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                Math.random() * 20 - 10
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            )
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            scene.add(sprite)
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        }
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        // 创建canvas文字方法
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        function createCanvasText(params) {
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            const defaultParams = { dpr: 1, maxWidth: 100, fontSize: 20, color: 'white', fontFamily: 'serif', align: 'center', border: false, ...params } // 默认参数
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            const { dpr, border, maxWidth, fontSize, align } = defaultParams
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            const devicePixelRatio = window.devicePixelRatio * dpr
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            // 准备 cnvas
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            const canvas = document.createElement('canvas')
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            canvas.width = maxWidth * devicePixelRatio
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            canvas.height = fontSize * devicePixelRatio
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            // 获取 2d 上下文
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            const ctx = canvas.getContext('2d')
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            ctx.imageSmoothingQuality = 'high'
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            ctx.scale(devicePixelRatio, devicePixelRatio)
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            // 创建文字
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            const createText = ({ text, color, fontSize, fontFamily }) => {
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                // 参数设定
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                ctx.fillStyle = color || defaultParams.color
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                ctx.font = fontSize || defaultParams.fontSize + 'px ' + fontFamily || defaultParams.fontFamily
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                // 文本长度计算
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                let textMaxNum = 0
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                let totalWidth = 0
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                for (let i = 0; i < text.length; i++) {
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                    const metrics = ctx.measureText(text[i])
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                    totalWidth += metrics.width;
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                    if (totalWidth > maxWidth) break
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                    textMaxNum++
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                }
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                text = text.slice(0, textMaxNum)
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                // 文字 绘制
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                const metrics = ctx.measureText(text) // 文本尺寸
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                const actualHeight = metrics.actualBoundingBoxAscent + metrics.actualBoundingBoxDescent // 实际文字高度
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                const textFillHeight = (canvas.height / devicePixelRatio - actualHeight) / 2 + metrics.actualBoundingBoxAscent
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                let textLeftOffset = 0
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                if (align === 'center') textLeftOffset = (canvas.width / devicePixelRatio - metrics.width) / 2
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                ctx.fillText(text, textLeftOffset, textFillHeight, canvas.width / devicePixelRatio)
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            }
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            return (parameters) => {
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                ctx.clearRect(0, 0, canvas.width, canvas.height)  // 清空  canvas 文字 
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                createText(parameters) // 创建文字
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                return canvas
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            }
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        }
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    </script>
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</body>
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</html> |