canvas力导布局

news2024/11/15 20:05:32

老规矩,先上效果图

<html>

<head>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        canvas {
            display: block;
            width: 100%;
            height: 100%;
            background: #000;
        }
    </style>
</head>

<body>
    <canvas id="network"></canvas>
</body>
<script>
    class TaskQueue {
        constructor() {
            this.taskList = []
            this.hasTaskDone = false
            this.status = 'do' // do or stop

            this.requestAnimationFrame = null
            this.requestAnimationFrameDrawBind = this.requestAnimationFrameDraw.bind(this)
        }
        addTask(func) {
            this.taskList.push(func)
            if (this.requestAnimationFrame === null) {
                this.addRequestAnimationFrame()
                this.do()
            }
        }
        do() {
            this.status = 'do'
            new Promise(res => {
                this.taskList[0] && this.taskList[0]()
                this.taskList.shift()
                this.hasTaskDone = true
                res()
            }).then(() => {
                if (this.status === 'do' && this.taskList.length) {
                    this.do()
                }
            })
        }
        stop() {
            this.status = 'stop'
        }
        requestAnimationFrameDraw() {
            this.stop()
            if (this.hasTaskDone && this.reDraw) {
                this.hasTaskDone = false
                this.reDraw()
            }
            if (this.taskList.length) {
                this.addRequestAnimationFrame()
                this.do()
            } else {
                this.clearRequestAnimationFrame()
            }
        }
        addRequestAnimationFrame() {
            this.requestAnimationFrame = window.requestAnimationFrame(this.requestAnimationFrameDrawBind)
        }
        clearRequestAnimationFrame() {
            window.cancelAnimationFrame(this.requestAnimationFrame)
            this.requestAnimationFrame = null
        }
        removeEvent() {
            this.stop()
            this.clearRequestAnimationFrame()
        }
    }

    class Layout extends TaskQueue {
        constructor(opt) {
            super(opt)

            this.qIndex = opt.layout.qIndex
            this.fStableL = opt.layout.fStableL
            this.fIndex = opt.layout.fIndex
            this.count = opt.layout.count || opt.nodes.length * Math.ceil(opt.nodes.length / 5)
            this.countForce = 0
        }
        doLayout() {
            this.countForce++
            if (this.countForce >= this.count) {
                return
            }

            // 计算开始
            this.forceComputed(this.arc, this.line)
            setTimeout(() => {
                this.addTask(() => {
                    this.doLayout();
                })
            })
        }
        forceComputed(nodes) {
            nodes.forEach(item => {
                item.translateX = 0
                item.translateY = 0
            })
            nodes.forEach((curNode, index) => {
                // 库仑力计算
                for (let i = index + 1; i < nodes.length; i++) {
                    let otherNode = nodes[i]
                    if (otherNode) {
                        this.computedXYByQ(curNode, otherNode)
                    }
                }
                // 弹簧力计算
                if (curNode.fromArcs?.length) {
                    curNode.fromArcs.forEach(id => {
                        let fromNode = nodes.filter(node => {
                            return node.id === id
                        })[0]
                        if (fromNode) {
                            this.computedXYByK(curNode, fromNode)
                        }
                    })
                }
                // 中心拉力
                if (curNode.fromArcs?.length) {
                    this.computedXYByK(curNode, {
                        xy: {
                            x: this.canvas.width / 2,
                            y: this.canvas.height / 2
                        }
                    })
                }
            })

            // let maxTranslate = 1
            // nodes.forEach(item => {
            //     if(item.translateX && Math.abs(item.translateX) > maxTranslate){
            //         maxTranslate = Math.abs(item.translateX)
            //     }
            //     if(item.translateY && Math.abs(item.translateY) > maxTranslate){
            //         maxTranslate = Math.abs(item.translateY)
            //     }
            // })
            // nodes.forEach(item => {
            //     if(item.translateX){
            //         item.x += item.translateX / maxTranslate
            //     }
            //     if(item.translateY){
            //         item.y += item.translateY / maxTranslate
            //     }
            // })
            nodes.forEach(item => {
                if (item.translateX) {
                    item.xy.x += item.translateX
                }
                if (item.translateY) {
                    item.xy.y += item.translateY
                }
            })
        }
        computedXYByQ(node1, node2) {
            let x1 = node1.xy.x
            let y1 = node1.xy.y
            let x2 = node2.xy.x
            let y2 = node2.xy.y
            let xl = x2 - x1
            let yl = y2 - y1
            let angle = Math.PI
            if (!xl) {
                if (y2 > y1) {
                    angle = -Math.PI / 2
                } else {
                    angle = Math.PI / 2
                }
            } else if (!yl) {
                if (x2 > x1) {
                    angle = 0
                } else {
                    angle = Math.PI
                }
            } else {
                angle = Math.atan(yl / xl)
            }
            let r = Math.sqrt(Math.pow(xl, 2) + Math.pow(yl, 2))
            if (r < 1) {
                r = 1
            }
            // 库仑力 r越大,库仑力越小
            let node1Q = (node1.fromNodes?.length || 0) + (node1.toNodes?.length || 0) + 1
            let node2Q = (node2.fromNodes?.length || 0) + (node2.toNodes?.length || 0) + 1
            let f = this.qIndex * node1Q * node2Q / Math.pow(r, 2)
            let fx = f * Math.cos(angle)
            let fy = f * Math.sin(angle)

            node1.translateX = node1.translateX
            node1.translateY = node1.translateY
            node2.translateX = node2.translateX
            node2.translateY = node2.translateY

            // node1.translateX -= fx
            // node2.translateX += fx
            // node1.translateY -= fy
            // node2.translateY += fy
            if (x2 > x1) {
                if (fx > 0) {
                    node1.translateX -= fx
                    node2.translateX += fx
                } else {
                    node1.translateX += fx
                    node2.translateX -= fx
                }
            } else {
                if (fx > 0) {
                    node1.translateX += fx
                    node2.translateX -= fx
                } else {
                    node1.translateX -= fx
                    node2.translateX += fx
                }
            }
            if (y2 > y1) {
                if (fy > 0) {
                    node1.translateY -= fy
                    node2.translateY += fy
                } else {
                    node1.translateY += fy
                    node2.translateY -= fy
                }
            } else {
                if (fy > 0) {
                    node1.translateY += fy
                    node2.translateY -= fy
                } else {
                    node1.translateY -= fy
                    node2.translateY += fy
                }
            }
        }
        computedXYByK(node1, node2) {
            let x1 = node1.xy.x
            let y1 = node1.xy.y
            let x2 = node2.xy.x
            let y2 = node2.xy.y
            let xl = x2 - x1
            let yl = y2 - y1
            let angle = Math.PI
            if (!xl) {
                if (y2 > y1) {
                    angle = -Math.PI / 2
                } else {
                    angle = Math.PI / 2
                }
            } else if (!yl) {
                if (x2 > x1) {
                    angle = 0
                } else {
                    angle = Math.PI
                }
            } else {
                angle = Math.atan(yl / xl)
            }
            let r = Math.sqrt(Math.pow(xl, 2) + Math.pow(yl, 2))
            if (r > this.fStableL * 2) {
                r = this.fStableL * 2
            } else if (r < 1) {
                r = 1
            }
            // 弹簧力
            let f = this.fIndex * (r - this.fStableL)
            let fx = f * Math.cos(angle)
            let fy = f * Math.sin(angle)

            node1.translateX = node1.translateX
            node1.translateY = node1.translateY
            node2.translateX = node2.translateX
            node2.translateY = node2.translateY

            if (f > 0) {
                // 拉力
                if (x2 > x1) {
                    if (fx > 0) {
                        node1.translateX += fx
                        node2.translateX -= fx
                    } else {
                        node1.translateX -= fx
                        node2.translateX += fx
                    }
                } else {
                    if (fx > 0) {
                        node1.translateX -= fx
                        node2.translateX += fx
                    } else {
                        node1.translateX += fx
                        node2.translateX -= fx
                    }
                }
                if (y2 > y1) {
                    if (fy > 0) {
                        node1.translateY += fy
                        node2.translateY -= fy
                    } else {
                        node1.translateY -= fy
                        node2.translateY += fy
                    }
                } else {
                    if (fy > 0) {
                        node1.translateY -= fy
                        node2.translateY += fy
                    } else {
                        node1.translateY += fy
                        node2.translateY -= fy
                    }
                }
            } else {
                // 弹力
                if (x2 > x1) {
                    if (fx > 0) {
                        node1.translateX -= fx
                        node2.translateX += fx
                    } else {
                        node1.translateX += fx
                        node2.translateX -= fx
                    }
                } else {
                    if (fx > 0) {
                        node1.translateX += fx
                        node2.translateX -= fx
                    } else {
                        node1.translateX -= fx
                        node2.translateX += fx
                    }
                }
                if (y2 > y1) {
                    if (fy > 0) {
                        node1.translateY -= fy
                        node2.translateY += fy
                    } else {
                        node1.translateY += fy
                        node2.translateY -= fy
                    }
                } else {
                    if (fy > 0) {
                        node1.translateY += fy
                        node2.translateY -= fy
                    } else {
                        node1.translateY -= fy
                        node2.translateY += fy
                    }
                }
            }

        }
    }

    class View extends Layout {
        constructor(opt) {
            super(opt)
            this.canvas = opt.canvas
            this.dpr = window.devicePixelRatio || 1

            this.nodes = opt.nodes
            this.paths = opt.paths

            this.circleStyle = opt.circleStyle
            this.lineStyle = opt.lineStyle

            this.line = []
            this.arc = []

            this.init()
        }
        init() {
            if (!this.canvas) {
                return
            }

            if (this.canvas.width !== Math.floor(this.canvas.offsetWidth * this.dpr) || this.canvas.height !== Math.floor(this.canvas.offsetHeight * this.dpr)) {
                this.canvas.width = Math.floor(this.canvas.offsetWidth * this.dpr)
                this.canvas.height = Math.floor(this.canvas.offsetHeight * this.dpr)
            }
            this.ctx = this.canvas.getContext('2d')

            this.addData(this.nodes, this.paths)
        }
        addData(nodes, paths) {
            if (nodes && nodes.length) {
                this.addArc(nodes)
            }
            if (paths && paths.length) {
                this.addLine(paths)
            }

            super.countForce = 0
            super.doLayout()
        }
        addArc(nodes) {
            // 数据多时可以考虑将初始化随机坐标范围与数据量做等比函数
            nodes.forEach(node => {
                this.arc.push({
                    id: node.id,
                    fromArcs: [],
                    toArcs: [],
                    xy: {
                        x: this.rand(0, this.canvas.width),
                        y: this.rand(0, this.canvas.height)
                    }
                })
            })
        }
        addLine(paths) {
            paths.forEach(path => {
                let fromArc = this.arc.filter(node => {
                    return node.id === path.from
                })[0]
                let toArc = this.arc.filter(node => {
                    return node.id === path.to
                })[0]
                fromArc.toArcs.push(toArc.id)
                toArc.fromArcs.push(fromArc.id)
                if (fromArc && toArc) {
                    this.line.push({
                        id: path.id,
                        from: path.from,
                        to: path.to,
                        fromArc,
                        toArc
                    })
                }
            })
        }
        reDraw() {
            this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height)
            this.draw()
        }
        draw() {
            this.line.forEach(item => {
                this.drawLine(item)
            })
            this.arc.forEach(item => {
                this.drawArc(item)
            })
        }
        drawLine(data) {
            this.ctx.save()
            this.ctx.translate(this.canvas.width / 2, this.canvas.height / 2)
            this.ctx.scale(this.scaleC, this.scaleC)
            this.ctx.translate(-this.canvas.width / 2, -this.canvas.height / 2)

            this.ctx.beginPath()
            this.ctx.lineWidth = this.lineStyle.width
            this.ctx.strokeStyle = this.lineStyle.color
            this.ctx.moveTo(data.fromArc.xy.x, data.fromArc.xy.y)
            this.ctx.lineTo(data.toArc.xy.x, data.toArc.xy.y)
            this.ctx.stroke()
            this.ctx.closePath()
            this.ctx.restore()
        }
        drawArc(data) {
            this.ctx.save()
            this.ctx.translate(this.canvas.width / 2, this.canvas.height / 2)
            this.ctx.scale(this.scaleC, this.scaleC)
            this.ctx.translate(-this.canvas.width / 2, -this.canvas.height / 2)

            this.ctx.beginPath()
            this.ctx.fillStyle = this.circleStyle.background
            this.ctx.arc(data.xy.x, data.xy.y, this.circleStyle.r, 0, 2 * Math.PI)
            this.ctx.fill()
            this.ctx.closePath()

            this.ctx.restore()
        }
        rand = (n, m) => {
            var c = m - n + 1
            return Math.floor(Math.random() * c + n)
        }
    }

    // 测试数据
    let data = {
        "nodes": [
            {
                "id": "36"
            },
            {
                "id": "50"
            },
            {
                "id": "20077"
            },
            {
                "id": "1090"
            },
            {
                "id": "1078"
            },
            {
                "id": "10007"
            },
            {
                "id": "20039"
            },
            {
                "id": "1074"
            },
            {
                "id": "20058"
            },
            {
                "id": "1062"
            },
            {
                "id": "10001"
            },
            {
                "id": "20076"
            },
            {
                "id": "1089"
            },
            {
                "id": "20038"
            },
            {
                "id": "1068"
            },
            {
                "id": "20057"
            },
            {
                "id": "1081"
            },
            {
                "id": "20070"
            },
            {
                "id": "1034"
            },
            {
                "id": "1077"
            },
            {
                "id": "10002"
            },
            {
                "id": "10003"
            },
            {
                "id": "20069"
            },
            {
                "id": "1002"
            },
            {
                "id": "47"
            },
            {
                "id": "10010"
            },
            {
                "id": "14"
            },
            {
                "id": "42"
            },
            {
                "id": "94"
            },
            {
                "id": "16"
            },
            {
                "id": "41"
            },
            {
                "id": "64"
            },
            {
                "id": "20002"
            },
            {
                "id": "73"
            },
            {
                "id": "1001"
            },
            {
                "id": "10009"
            },
            {
                "id": "10008"
            },
            {
                "id": "10006"
            },
            {
                "id": "10005"
            },
            {
                "id": "10004"
            },
            {
                "id": "33"
            },
            {
                "id": "10"
            },
            {
                "id": "18"
            },
            {
                "id": "70"
            },
            {
                "id": "98"
            },
            {
                "id": "20"
            },
            {
                "id": "24"
            },
            {
                "id": "20001"
            }
        ],
        "paths": [
            {
                "id": "606",
                "from": "50",
                "to": "36"
            },
            {
                "id": "346",
                "from": "20077",
                "to": "1090"
            },
            {
                "id": "343",
                "from": "1078",
                "to": "10007"
            },
            {
                "id": "382",
                "from": "20039",
                "to": "1074"
            },
            {
                "id": "419",
                "from": "20058",
                "to": "1062"
            },
            {
                "id": "344",
                "from": "1078",
                "to": "10001"
            },
            {
                "id": "356",
                "from": "20076",
                "to": "1089"
            },
            {
                "id": "439",
                "from": "20038",
                "to": "1068"
            },
            {
                "id": "417",
                "from": "20057",
                "to": "1081"
            },
            {
                "id": "358",
                "from": "20070",
                "to": "1078"
            },
            {
                "id": "438",
                "from": "20038",
                "to": "1034"
            },
            {
                "id": "248",
                "from": "1077",
                "to": "10002"
            },
            {
                "id": "249",
                "from": "1077",
                "to": "10003"
            },
            {
                "id": "364",
                "from": "20069",
                "to": "1077"
            },
            {
                "id": "4797",
                "from": "1002",
                "to": "10003"
            },
            {
                "id": "4787",
                "from": "1002",
                "to": "10002"
            },
            {
                "id": "223",
                "from": "1002",
                "to": "10003"
            },
            {
                "id": "222",
                "from": "1002",
                "to": "10002"
            },
            {
                "id": "2659",
                "from": "1002",
                "to": "47"
            },
            {
                "id": "4777",
                "from": "1002",
                "to": "10001"
            },
            {
                "id": "4867",
                "from": "1002",
                "to": "10010"
            },
            {
                "id": "1466",
                "from": "14",
                "to": "1002"
            },
            {
                "id": "1437",
                "from": "42",
                "to": "1002"
            },
            {
                "id": "1414",
                "from": "94",
                "to": "1002"
            },
            {
                "id": "1411",
                "from": "16",
                "to": "1002"
            },
            {
                "id": "1395",
                "from": "16",
                "to": "1002"
            },
            {
                "id": "1382",
                "from": "41",
                "to": "1002"
            },
            {
                "id": "1377",
                "from": "64",
                "to": "1002"
            },
            {
                "id": "436",
                "from": "20002",
                "to": "1002"
            },
            {
                "id": "2658",
                "from": "73",
                "to": "1002"
            },
            {
                "id": "4856",
                "from": "1001",
                "to": "10009"
            },
            {
                "id": "4846",
                "from": "1001",
                "to": "10008"
            },
            {
                "id": "4836",
                "from": "1001",
                "to": "10007"
            },
            {
                "id": "4826",
                "from": "1001",
                "to": "10006"
            },
            {
                "id": "4816",
                "from": "1001",
                "to": "10005"
            },
            {
                "id": "4806",
                "from": "1001",
                "to": "10004"
            },
            {
                "id": "4796",
                "from": "1001",
                "to": "10003"
            },
            {
                "id": "4786",
                "from": "1001",
                "to": "10002"
            },
            {
                "id": "4776",
                "from": "1001",
                "to": "10001"
            },
            {
                "id": "221",
                "from": "1001",
                "to": "10001"
            },
            {
                "id": "4866",
                "from": "1001",
                "to": "10010"
            },
            {
                "id": "1469",
                "from": "33",
                "to": "1001"
            },
            {
                "id": "1459",
                "from": "10",
                "to": "1001"
            },
            {
                "id": "1448",
                "from": "18",
                "to": "1001"
            },
            {
                "id": "1406",
                "from": "70",
                "to": "1001"
            },
            {
                "id": "1396",
                "from": "47",
                "to": "1001"
            },
            {
                "id": "1369",
                "from": "98",
                "to": "1001"
            },
            {
                "id": "1365",
                "from": "20",
                "to": "1001"
            },
            {
                "id": "1363",
                "from": "24",
                "to": "1001"
            },
            {
                "id": "406",
                "from": "20001",
                "to": "1001"
            }
        ]
    }
    // canvas dom
    const canvas = document.getElementById('network');

    new View({
        canvas,
        nodes: data.nodes,
        paths: data.paths,
        circleStyle: {
            r: 10,
            background: '#FFFFFF'
        },
        lineStyle: {
            width: 1,
            color: '#FFFFFF'
        },
        layout: {
            qIndex: 2000, // 库仑力系数,值越大,库仑力越大
            fStableL: 80,
            fIndex: 0.1, // 拉力系数,数值越大,力越大
        }
    })
</script>

</html>

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