我得到了一个D3v6图，其中包含节点的上下文菜单。如果单击，则可以添加到另一个节点的链接。我的问题是缩放函数，我在根SVG上声明了它：
var svg = d3.select("svg")
.attr("class", "canvas")
.attr("width", width)
.attr("height", height)
.call(d3.zoom().on("zoom", function (event) {
svg.attr("transform", event.transform)
}))
//.on("mousedown", mousedownSVG)
.on("mousemove", mousemoveSVG)
.on("mouseup", mouseupSVG)
.append("g")
情况1:不要缩放，使用添加链接功能将节点2与节点0连接起来。完全没有问题
情况2:重新加载代码段，放大然后使用添加链接功能。dragLine不在鼠标位置。不知怎的，缩放功能破坏了我的图形的比例，导致返回错误的位置。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>D3v6 Refactor</title>
<!-- call external d3.js framework -->
<script src="https://d3js.org/d3.v6.js"></script>
</head>
<style>
body {
overflow: hidden;
background-color: rgb(220, 220, 220);
margin: 0px;
}
.node {
stroke: white;
stroke-width: 2px;
cursor: pointer;
}
.node:hover {
stroke: red
}
.link {
fill: none;
cursor: default;
stroke: rgb(0, 0, 0);
stroke-width: 3px;
}
.dragline {
stroke-width: 2;
pointer-events: none;
}
.dragline.hidden {
stroke-width: 0;
}
#context-menu-node {
font-family: "Open Sans", sans-serif;
position: fixed;
z-index: 10000;
width: 190px;
background: whitesmoke;
border: 2px;
border-radius: 6px;
border-color: white;
border-style: solid;
transform: scale(0);
transform-origin: top left;
}
#context-menu-node.active {
transform: scale(1);
transition: transform 200ms ease-in-out;
}
#context-menu-node .item {
padding: 8px 10px;
font-size: 15px;
color: black;
}
#context-menu-node .item i {
display: inline-block;
margin-right: 5px;
}
#context-menu-node hr {
margin: 5px 0px;
border-color: whitesmoke;
}
#context-menu-node .item:hover {
background: lightblue;
}
</style>
<body>
<!-- right click context menu node -->
<div id="context-menu-node">
<div id="addLink" class="item">
<i class="fas fa-link"></i></i> Add Link
</div>
<hr>
<div id="addNode" class="item">
<i class="fas fa-link"></i></i> Add Node
</div>
</div>
<svg id="svg"> </svg>
<script>
var graph = {
"nodes": [
{
"id": 0,
},
{
"id": 1,
},
{
"id": 2,
}
],
"links": [
{
"source": 0,
"target": 1,
},
{
"source": 1,
"target": 2,
}
]
}
var width = window.innerWidth
var height = window.innerHeight
var svg = d3.select("svg")
.attr("class", "canvas")
.attr("width", width)
.attr("height", height)
.call(d3.zoom().on("zoom", function (event) {
svg.attr("transform", event.transform)
}))
//.on("mousedown", mousedownSVG)
.on("mousemove", mousemoveSVG)
.on("mouseup", mouseupSVG)
.append("g")
// remove zoom on dblclick listener
d3.select("svg").on("dblclick.zoom", null)
var linkContainer = svg.append("g").attr("class", "linkContainer")
var nodeContainer = svg.append("g").attr("class", "nodeContainer")
var mousedownNode = "";
var targetLink = "";
var addLinkClicked = false;
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function (d) {
return d.id;
}).distance(100))
.force("charge", d3.forceManyBody().strength(-500))
.force("center", d3.forceCenter(width / 2, height / 2))
.force("collision", d3.forceCollide().radius(50))
var dragLine = svg.append("path")
.attr("class", "link dragline")
.attr("d", "M0,0 L0,0");
initialize()
function initialize() {
link = linkContainer.selectAll(".link")
.data(graph.links)
.join("line")
.attr("class", "link")
node = nodeContainer.selectAll(".node")
.data(graph.nodes, d => d.id)
.join("g")
.attr("class", "node")
.call(d3.drag()
.on("start", dragStarted)
.on("drag", dragged)
.on("end", dragEnded)
)
node
.data(graph.nodes, d => d.id)
.append("circle")
.attr("r", 30)
.style("fill", "whitesmoke")
.on("contextmenu", contextMenuNode)
.on("mouseenter", (event, d) => {
targetLink = d
})
.on("mousedown", (event, d) => {
mousedownNode = d;
})
.on("click", function (event, d) {
if (!addLinkClicked) return
// needed by FF
dragLine
.classed('hidden', true)
console.log(targetLink.id)
graph.links.push({ source: thisElement.id, target: targetLink.id });
addLinkClicked = false;
initialize();
simulation.alpha(0.3).restart()
});
node
.append("text")
.style("class", "icon")
.attr("font-family", "FontAwesome")
.attr("dominant-baseline", "central")
.attr("text-anchor", "middle")
.attr("font-size", 30)
.attr("fill", "black")
.attr("stroke-width", "0px")
.attr("pointer-events", "none")
.text((d) => {
return d.id
})
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation
.force("link")
.links(graph.links)
}
function contextMenuNode(event, d) {
thisElement = d
event.preventDefault()
document.getElementById("context-menu-node").classList.remove("active")
var contextMenu = document.getElementById("context-menu-node")
contextMenu.style.top = event.clientY + "px"
contextMenu.style.left = event.clientX + "px"
contextMenu.classList.add("active")
window.addEventListener("click", function () {
contextMenu.classList.remove("active")
})
document.getElementById("addNode").addEventListener("click", addNode)
document.getElementById("addLink").addEventListener("click", addLink)
}
function addLink() {
addLinkClicked = true
const point = d3.pointer(event)
dragLine
.classed("hidden", false)
.attr('d', `M${thisElement.x},${thisElement.y}L${thisElement.x},${thisElement.y}`);
}
function addNode() {
var newID = Math.floor(Math.random() * 1000)
graph.nodes.push({
"id": newID
})
graph.links.push({ source: newID, target: thisElement.id })
initialize()
simulation.alpha(0.3).restart()
}
/*
function mousedownSVG(event) {
var point = d3.pointer(event)
var newNode = { id: graph.nodes.length, x: point[0], y: point[1] }
graph.nodes.push(newNode)
initialize()
simulation.alpha(0.3).restart()
}
*/
function mousemoveSVG(event) {
if (!addLinkClicked) return
const point = d3.pointer(event)
// update drag line
dragLine.attr('d', `M${mousedownNode.x},${mousedownNode.y}L${point[0]},${point[1]}`);
}
function mouseupSVG(event) {
if (mousedownNode) {
//hide drag line
dragLine
.classed("hidden", true)
}
}
function ticked() {
// update link positions
link
.attr("x1", function (d) {
return d.source.x;
})
.attr("y1", function (d) {
return d.source.y;
})
.attr("x2", function (d) {
return d.target.x;
})
.attr("y2", function (d) {
return d.target.y;
});
// update node positions
node
.attr("transform", function (d) {
return "translate(" + d.x + ", " + d.y + ")";
});
}
function dragStarted(event, d) {
if (!event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(event, d) {
d.fx = event.x;
d.fy = event.y;
}
function dragEnded(event, d) {
if (!event.active) simulation.alphaTarget(0);
d.fx = undefined;
d.fy = undefined;
}
</script>
</body>
</html>知道怎么解决这个问题吗？
一般问题由@Andrew Reid 回答
对于您的具体问题，请尝试以下内容来说明发生了什么：
- 在
mousemoveSVG函数中包含console.log(point) - 运行代码段
- 右键单击节点2并添加链接
- 将指针移动到"零"节点的中心，并在控制台中观察
[x, y] - 做一些平移和缩放
- 移动
dragline-您将看到[x, y]已更改，dragline已关闭 - 停止代码段并在
mousemoveSVG中将此行更新为const point = d3.pointer(event, svg.node()); - 现在重复上面的测试-对于任何不同的平移/缩放操作，"零"节点中心的指针都应该具有相同的
[x,y]
d3.pointer的第二个参数称为目标：
如果目标是SVG元素，则事件的坐标为使用屏幕坐标变换的逆变换矩阵
用这个屏幕坐标变换矩阵变换指针的[x,y]基本上就是说让我的鼠标与缩放保持同步。
这是您的完整更新代码-我在log填充代码片段时注释掉了它，但您可以取消注释以尝试上面的步骤。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>D3v6 Refactor</title>
<!-- call external d3.js framework -->
<script src="https://d3js.org/d3.v6.js"></script>
</head>
<style>
body {
overflow: hidden;
background-color: rgb(220, 220, 220);
margin: 0px;
}
.node {
stroke: white;
stroke-width: 2px;
cursor: pointer;
}
.node:hover {
stroke: red
}
.link {
fill: none;
cursor: default;
stroke: rgb(0, 0, 0);
stroke-width: 3px;
}
.dragline {
stroke-width: 2;
pointer-events: none;
}
.dragline.hidden {
stroke-width: 0;
}
#context-menu-node {
font-family: "Open Sans", sans-serif;
position: fixed;
z-index: 10000;
width: 190px;
background: whitesmoke;
border: 2px;
border-radius: 6px;
border-color: white;
border-style: solid;
transform: scale(0);
transform-origin: top left;
}
#context-menu-node.active {
transform: scale(1);
transition: transform 200ms ease-in-out;
}
#context-menu-node .item {
padding: 8px 10px;
font-size: 15px;
color: black;
}
#context-menu-node .item i {
display: inline-block;
margin-right: 5px;
}
#context-menu-node hr {
margin: 5px 0px;
border-color: whitesmoke;
}
#context-menu-node .item:hover {
background: lightblue;
}
</style>
<body>
<!-- right click context menu node -->
<div id="context-menu-node">
<div id="addLink" class="item">
<i class="fas fa-link"></i></i> Add Link
</div>
<hr>
<div id="addNode" class="item">
<i class="fas fa-link"></i></i> Add Node
</div>
</div>
<svg id="svg"> </svg>
<script>
var graph = {
"nodes": [
{
"id": 0,
},
{
"id": 1,
},
{
"id": 2,
}
],
"links": [
{
"source": 0,
"target": 1,
},
{
"source": 1,
"target": 2,
}
]
}
var width = window.innerWidth
var height = window.innerHeight
var svg = d3.select("svg")
.attr("class", "canvas")
.attr("width", width)
.attr("height", height)
.call(d3.zoom().on("zoom", function (event) {
svg.attr("transform", event.transform)
}))
//.on("mousedown", mousedownSVG)
.on("mousemove", mousemoveSVG)
.on("mouseup", mouseupSVG)
.append("g")
// remove zoom on dblclick listener
d3.select("svg").on("dblclick.zoom", null)
var linkContainer = svg.append("g").attr("class", "linkContainer")
var nodeContainer = svg.append("g").attr("class", "nodeContainer")
var mousedownNode = "";
var targetLink = "";
var addLinkClicked = false;
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function (d) {
return d.id;
}).distance(100))
.force("charge", d3.forceManyBody().strength(-500))
.force("center", d3.forceCenter(width / 2, height / 2))
.force("collision", d3.forceCollide().radius(50))
var dragLine = svg.append("path")
.attr("class", "link dragline")
.attr("d", "M0,0 L0,0");
initialize()
function initialize() {
link = linkContainer.selectAll(".link")
.data(graph.links)
.join("line")
.attr("class", "link")
node = nodeContainer.selectAll(".node")
.data(graph.nodes, d => d.id)
.join("g")
.attr("class", "node")
.call(d3.drag()
.on("start", dragStarted)
.on("drag", dragged)
.on("end", dragEnded)
)
node
.data(graph.nodes, d => d.id)
.append("circle")
.attr("r", 30)
.style("fill", "whitesmoke")
.on("contextmenu", contextMenuNode)
.on("mouseenter", (event, d) => {
targetLink = d
})
.on("mousedown", (event, d) => {
mousedownNode = d;
})
.on("click", function (event, d) {
if (!addLinkClicked) return
// needed by FF
dragLine
.classed('hidden', true)
console.log(targetLink.id)
graph.links.push({ source: thisElement.id, target: targetLink.id });
addLinkClicked = false;
initialize();
simulation.alpha(0.3).restart()
});
node
.append("text")
.style("class", "icon")
.attr("font-family", "FontAwesome")
.attr("dominant-baseline", "central")
.attr("text-anchor", "middle")
.attr("font-size", 30)
.attr("fill", "black")
.attr("stroke-width", "0px")
.attr("pointer-events", "none")
.text((d) => {
return d.id
})
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation
.force("link")
.links(graph.links)
}
function contextMenuNode(event, d) {
thisElement = d
event.preventDefault()
document.getElementById("context-menu-node").classList.remove("active")
var contextMenu = document.getElementById("context-menu-node")
contextMenu.style.top = event.clientY + "px"
contextMenu.style.left = event.clientX + "px"
contextMenu.classList.add("active")
window.addEventListener("click", function () {
contextMenu.classList.remove("active")
})
document.getElementById("addNode").addEventListener("click", addNode)
document.getElementById("addLink").addEventListener("click", addLink)
}
function addLink() {
addLinkClicked = true
const point = d3.pointer(event)
dragLine
.classed("hidden", false)
.attr('d', `M${thisElement.x},${thisElement.y}L${thisElement.x},${thisElement.y}`);
}
function addNode() {
var newID = Math.floor(Math.random() * 1000)
graph.nodes.push({
"id": newID
})
graph.links.push({ source: newID, target: thisElement.id })
initialize()
simulation.alpha(0.3).restart()
}
/*
function mousedownSVG(event) {
var point = d3.pointer(event)
var newNode = { id: graph.nodes.length, x: point[0], y: point[1] }
graph.nodes.push(newNode)
initialize()
simulation.alpha(0.3).restart()
}
*/
function mousemoveSVG(event) {
if (!addLinkClicked) return
const point = d3.pointer(event, svg.node()); // <--- add svg.node() as 'target'
//console.log(point);
// update drag line
dragLine.attr('d', `M${mousedownNode.x},${mousedownNode.y}L${point[0]},${point[1]}`);
}
function mouseupSVG(event) {
if (mousedownNode) {
//hide drag line
dragLine
.classed("hidden", true)
}
}
function ticked() {
// update link positions
link
.attr("x1", function (d) {
return d.source.x;
})
.attr("y1", function (d) {
return d.source.y;
})
.attr("x2", function (d) {
return d.target.x;
})
.attr("y2", function (d) {
return d.target.y;
});
// update node positions
node
.attr("transform", function (d) {
return "translate(" + d.x + ", " + d.y + ")";
});
}
function dragStarted(event, d) {
if (!event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(event, d) {
d.fx = event.x;
d.fy = event.y;
}
function dragEnded(event, d) {
if (!event.active) simulation.alphaTarget(0);
d.fx = undefined;
d.fy = undefined;
}
</script>
</body>
</html>