7

我在 vis.js 中有一个包含许多节点的网络图。选择某个组时，我想平移和缩放图形，以便该组的所有节点都适合屏幕。

我正在遍历图中的每个节点并为我感兴趣的所有节点计算一个边界框，然后我使用该moveTo方法将图形移动并缩放到该边界框的中心。伪代码：

var allNodes = data.nodes.get({
    returnType: "Object"
});
var bounds;
for (n in allNodes) {
    if (matchesCondition(allNodes[n])) {
        bounds = extendBounds(bounds, graph.getBoundingBox(allNodes[n]));                   
    }
}
var newViewport = {
    position: {
        x: (bounds.x1+bounds.x2)/2;
        y: (bounds.y1+bounds.y2)/2;
    },
    // What is the visible width, where do I get it from?
    scale: Math.min(??? / (bounds.x2-bounds.x1), ??? / (bounds.y2-bounds.y1))
}
graph.moveTo(newViewport);

问题：我如何计算比例，即我用什么替换??? 在上面的伪代码中？

4

1 回答 1

9

Vis.js 组示例中的示例数据。

为了适应视口，您可以简单地使用本机.fit()方法。由于文档不提供 hashtaggable 链接，以下是 API 描述：

缩小以使所有节点都适合画布。您可以提供选项来自定义它：

{
  nodes:[Array of nodeIds],
  animation: { //can be a boolean too
    duration: Number
    easingFunction: String
  }
}

节点可用于缩放以仅适合视图中的特定节点。

考虑到这一点，我们需要做的就是获取给定组中的所有节点。令人惊讶的是，用户级 API 似乎没有为此提供方法（？），因此需要一个小的过滤方法。

//TODO: Is there no user-land API for this?
var getGroup = function getGroup(nodeId) {
  var nodesHandler = network.nodesHandler;
  var innerNodes = nodesHandler.body.nodes;
  //Lazily assume ids match indices
  var node = innerNodes[nodeId];
  return node.options.group;
};

var getGroupNodes = function getGroupNodes(group) {
  // http://elijahmanor.com/reducing-filter-and-map-down-to-reduce/
  var filtered = nodes.reduce(function(output, node) {
    if (node.group === group) {
      output.push(node.id);
    }
    return output;
  }, []);
  return filtered;
};

//START Vis.js group example

var color = 'gray';
var len = undefined;

var nodes = [{
  id: 0,
  label: "0",
  group: 0
}, {
  id: 1,
  label: "1",
  group: 0
}, {
  id: 2,
  label: "2",
  group: 0
}, {
  id: 3,
  label: "3",
  group: 1
}, {
  id: 4,
  label: "4",
  group: 1
}, {
  id: 5,
  label: "5",
  group: 1
}, {
  id: 6,
  label: "6",
  group: 2
}, {
  id: 7,
  label: "7",
  group: 2
}, {
  id: 8,
  label: "8",
  group: 2
}, {
  id: 9,
  label: "9",
  group: 3
}, {
  id: 10,
  label: "10",
  group: 3
}, {
  id: 11,
  label: "11",
  group: 3
}, {
  id: 12,
  label: "12",
  group: 4
}, {
  id: 13,
  label: "13",
  group: 4
}, {
  id: 14,
  label: "14",
  group: 4
}, {
  id: 15,
  label: "15",
  group: 5
}, {
  id: 16,
  label: "16",
  group: 5
}, {
  id: 17,
  label: "17",
  group: 5
}, {
  id: 18,
  label: "18",
  group: 6
}, {
  id: 19,
  label: "19",
  group: 6
}, {
  id: 20,
  label: "20",
  group: 6
}, {
  id: 21,
  label: "21",
  group: 7
}, {
  id: 22,
  label: "22",
  group: 7
}, {
  id: 23,
  label: "23",
  group: 7
}, {
  id: 24,
  label: "24",
  group: 8
}, {
  id: 25,
  label: "25",
  group: 8
}, {
  id: 26,
  label: "26",
  group: 8
}, {
  id: 27,
  label: "27",
  group: 9
}, {
  id: 28,
  label: "28",
  group: 9
}, {
  id: 29,
  label: "29",
  group: 9
}];
var edges = [{
  from: 1,
  to: 0
}, {
  from: 2,
  to: 0
}, {
  from: 4,
  to: 3
}, {
  from: 5,
  to: 4
}, {
  from: 4,
  to: 0
}, {
  from: 7,
  to: 6
}, {
  from: 8,
  to: 7
}, {
  from: 7,
  to: 0
}, {
  from: 10,
  to: 9
}, {
  from: 11,
  to: 10
}, {
  from: 10,
  to: 4
}, {
  from: 13,
  to: 12
}, {
  from: 14,
  to: 13
}, {
  from: 13,
  to: 0
}, {
  from: 16,
  to: 15
}, {
  from: 17,
  to: 15
}, {
  from: 15,
  to: 10
}, {
  from: 19,
  to: 18
}, {
  from: 20,
  to: 19
}, {
  from: 19,
  to: 4
}, {
  from: 22,
  to: 21
}, {
  from: 23,
  to: 22
}, {
  from: 22,
  to: 13
}, {
  from: 25,
  to: 24
}, {
  from: 26,
  to: 25
}, {
  from: 25,
  to: 7
}, {
  from: 28,
  to: 27
}, {
  from: 29,
  to: 28
}, {
  from: 28,
  to: 0
}];

// create a network
var container = document.getElementById('mynetwork');
var data = {
  nodes: nodes,
  edges: edges
};
var options = {
  nodes: {
    shape: 'dot',
    size: 30,
    font: {
      size: 32,
      color: '#ffffff'
    },
    borderWidth: 2
  },
  edges: {
    width: 2
  }
};
network = new vis.Network(container, data, options);

//END Vis.js group example

network.on("click", function(e) {
  //Zoom only on single node clicks, zoom out otherwise
  if (e.nodes.length !== 1) {
    network.fit();
    return;
  }
  var nodeId = e.nodes[0];
  //Find out what group the node belongs to
  var group = getGroup(nodeId);
  //TODO: How do you want to handle ungrouped nodes?
  if (group === undefined) return;
  var groupNodes = getGroupNodes(group);
  network.fit({
    nodes: groupNodes
  });
});
html,
body,
#mynetwork {
  width: 100%;
  height: 100%;
  margin: 0;
}
<script src="http://cdnjs.cloudflare.com/ajax/libs/vis/4.3.0/vis.min.js"></script>
<div id="mynetwork"></div>

于 2015-07-01T19:40:51.007 回答