JointJS: External anchor

by Roman Bruckner

HTML

<html>

  <head>
    <link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.2/css/all.min.css" />
  </head>

  <body>
    <!-- content -->
    <div id="paper" style="margin: 20px;"></div>

    <!-- dependencies -->
    <script src="https://cdn.jsdelivr.net/npm/@joint/[email protected]/dist/joint.min.js"></script>
  </body>

</html>

JavaScript

const graph = new joint.dia.Graph({}, {
    cellNamespace: joint.shapes
});

const TARGET_SEGMENT_LENGTH = 100;

const paper = new joint.dia.Paper({
    el: document.getElementById('paper'),
    width: 800,
    height: 900,
    model: graph,
    cellViewNamespace: joint.shapes,
    gridSize: 10,
    async: true,
    sorting: joint.dia.Paper.sorting.APPROX,
    defaultConnectionPoint: {
        name: 'boundary',
    },
    defaultRouter: function(vertices, opt, linkView) {

        return joint.routers.manhattan(vertices, {
            endDirections: ['left'],
            fallbackRouter: function(vertices, opt, linkView) {
                const { sourceBBox, targetBBox } = linkView;
                const right = targetBBox.leftMiddle();
                const left = sourceBBox.rightMiddle();
                return [{
                    x: (right.x + left.x) / 2,
                    y: left.y
                }, {
                    x: (right.x + left.x) / 2,
                    y: right.y
                }];
            },
            padding: {
                left: TARGET_SEGMENT_LENGTH
            }
        }, linkView);
    }
});

// Example

const el1 = new joint.shapes.standard.Rectangle({
    position: {
        x: 10,
        y: 270
    },
    size: {
        width: 100,
        height: 90
    },
    attrs: {
        label: {
            text: 'A'
        }
    }
});
const el2 = new joint.shapes.standard.Rectangle({
    position: {
        x: 400,
        y: 170
    },
    size: {
        width: 100,
        height: 90
    },
    attrs: {
        label: {
            text: 'B'
        }
    }
});

const l1 = new joint.shapes.standard.Link({
    source: {
        id: el1.id
    },
    target: {
        id: el2.id,
        // anchor: {
        //     name: 'left',
        //     args: {
        //         dx: -TARGET_SEGMENT_LENGTH
        //     }
        // }
    },
    attrs: {
        line: {
            strokeWidth: 3
        }
   ...