": {
                  "x": { "scale": "x", "field": "x" },
                  "y": { "scale": "y", "field": "y" },
                  "stroke": { "value": "#276EB8" },
                  "strokeWidth": { "value": 4 }
                }
              }
            }
          ]
        }
      ]
    }

    const size = 500000;
    const data = generateData(size, [
      sampleCounter('key'),
      sampleNominal('category', 'abcdefghij'),
      sampleNormal('u', 0, 2),
      sampleNormal('v', 10, 5),
      sampl