{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "width": 750,
  "height": 500,
  "padding": 0,
  "autosize": "none",

  "signals": [
    {
      "name": "scale", "value": 0.05,
      "bind": {"input": "range", "min": 0.005, "max": 0.1, "step": 0.001}
    },
    {
      "name": "offset", "value": 0,
      "bind": {"input": "range", "min": 0, "max": 10, "step": 0.1}
    },
    {
      "name": "smooth", "value": true, "bind": {"input": "checkbox"}
    }
  ],

  "data": [
    {
      "name": "source",
      "values": [{"width": 150, "height": 100}]
    }
  ],

  "scales": [
    {
      "name": "color",
      "type": "linear",
      "zero": true,
      "domain": [-1, 1],
      "range": {"scheme": "spectral"}
    }
  ],

  "marks": [
    {
      "type": "image",
      "from": {"data": "source"},
      "encode": {
        "update": {
          "x": {"value": 0},
          "y": {"value": 0},
          "width": {"signal": "width"},
          "height": {"signal": "height"},
          "aspect": {"value": false},
          "smooth": {"signal": "smooth"}
        }
      },
      "transform": [
        {
          "type": "heatmap",
          "field": "datum",
          "color": {"expr": "scale('color', sin(offset + scale * (datum.$x + datum.$y)) * sin(scale * (datum.$x - datum.$y)))"},
          "opacity": 1
        }
      ]
    }
  ]
}
