I've managed to get something working with Vega, compiling your Vega-lite spec into Vega first:
npx -p vega -p vega-lite vl2vg vega-lite-spec.json
then I've added to any signal who listened the view-click event and additional dimention event to listen, and in that case return a null selection on update:
{
"$schema": "https://vega.github.io/schema/vega/v5.json",
"background": "white",
"padding": 5,
"width": 200,
"height": 200,
"style": "cell",
"data": [
{"name": "selection_store"},
{
"name": "source_0",
"values": [
{
"dimention1": 1,
"dimention2": "C",
"data": [
{"x": 1, "y": 1},
{"x": 2, "y": 1},
{"x": 3, "y": 1},
{"x": 4, "y": 1},
{"x": 5, "y": 1}
]
},
{
"dimention1": 2,
"dimention2": "B",
"data": [
{"x": 1, "y": 2},
{"x": 2, "y": 2},
{"x": 3, "y": 2},
{"x": 4, "y": 2},
{"x": 5, "y": 2}
]
},
{
"dimention1": 3,
"dimention2": "A",
"data": [
{"x": 1, "y": 3},
{"x": 2, "y": 3},
{"x": 3, "y": 3},
{"x": 4, "y": 3},
{"x": 5, "y": 3}
]
}
]
},
{
"name": "data_0",
"source": "source_0",
"transform": [
{"type": "flatten", "fields": ["data"], "as": ["points"]},
{
"type": "formula",
"expr": "datum[\"points\"] && datum[\"points\"][\"x\"]",
"as": "points.x"
},
{
"type": "formula",
"expr": "datum[\"points\"] && datum[\"points\"][\"y\"]",
"as": "points.y"
},
{"type": "formula", "expr": "datum[dimention]", "as": "group"}
]
}
],
"signals": [
{
"name": "unit",
"value": {},
"on": [
{"events": "mousemove", "update": "isTuple(group()) ? group() : unit"}
]
},
{
"name": "selection_group_legend",
"value": null,
"on": [
{
"events": [
{
"source": "view",
"type": "click",
"markname": "group_legend_symbols"
},
{
"source": "view",
"type": "click",
"markname": "group_legend_labels"
},
{
"source": "view",
"type": "click",
"markname": "group_legend_entries"
}
],
"update": "isDefined(datum.value) ? datum.value : item().items[0].items[0].datum.value",
"force": true
},
{
"events": [{"source": "view", "type": "click"}],
"update": "!event.item || !datum ? null : selection_group_legend",
"force": true
},
{
"events": [{"signal": "dimention"}],
"update": "null",
"force": true
}
]
},
{
"name": "selection",
"update": "vlSelectionResolve(\"selection_store\", \"union\", true, true)"
},
{
"name": "dimention",
"value": "dimention1",
"bind": {"input": "select", "options": ["dimention1", "dimention2"]}
},
{
"name": "selection_tuple",
"update": "selection_group_legend !== null ? {fields: selection_tuple_fields, values: [selection_group_legend]} : null"
},
{
"name": "selection_tuple_fields",
"value": [{"type": "E", "field": "group"}]
},
{
"name": "selection_toggle",
"value": false,
"on": [
{
"events": {"merge": [{"source": "view", "type": "click"}]},
"update": "true"
},
{
"events": [{"signal": "dimention"}],
"update": "null",
"force": true
}
]
},
{
"name": "selection_modify",
"on": [
{
"events": {"signal": "selection_tuple"},
"update": "modify(\"selection_store\", selection_toggle ? null : selection_tuple, selection_toggle ? null : true, selection_toggle ? selection_tuple : null)"
}
]
}
],
"marks": [
{
"name": "pathgroup",
"type": "group",
"from": {
"facet": {
"name": "faceted_path_main",
"data": "data_0",
"groupby": ["group"]
}
},
"encode": {
"update": {
"width": {"field": {"group": "width"}},
"height": {"field": {"group": "height"}}
}
},
"marks": [
{
"name": "marks",
"type": "line",
"style": ["line"],
"sort": {"field": "datum[\"points.x\"]"},
"interactive": true,
"from": {"data": "faceted_path_main"},
"encode": {
"update": {
"stroke": {"scale": "color", "field": "group"},
"opacity": [
{
"test": "!length(data(\"selection_store\")) || vlSelectionTest(\"selection_store\", datum)",
"value": 1
},
{"value": 0}
],
"description": {
"signal": "\"points.x: \" + (format(datum[\"points.x\"], \"\")) + \"; points.y: \" + (format(datum[\"points.y\"], \"\")) + \"; group: \" + (isValid(datum[\"group\"]) ? datum[\"group\"] : \"\"+datum[\"group\"])"
},
"x": {"scale": "x", "field": "points\\.x"},
"y": {"scale": "y", "field": "points\\.y"},
"defined": {
"signal": "isValid(datum[\"points.x\"]) && isFinite(+datum[\"points.x\"]) && isValid(datum[\"points.y\"]) && isFinite(+datum[\"points.y\"])"
}
}
}
}
]
}
],
"scales": [
{
"name": "x",
"type": "linear",
"domain": {"data": "data_0", "field": "points\\.x"},
"range": [0, {"signal": "width"}],
"nice": true,
"zero": false
},
{
"name": "y",
"type": "linear",
"domain": {"data": "data_0", "field": "points\\.y"},
"range": [{"signal": "height"}, 0],
"nice": true,
"zero": true
},
{
"name": "color",
"type": "ordinal",
"domain": {"data": "data_0", "field": "group", "sort": true},
"range": "category"
}
],
"axes": [
{
"scale": "x",
"orient": "bottom",
"gridScale": "y",
"grid": true,
"tickCount": {"signal": "ceil(width/40)"},
"domain": false,
"labels": false,
"aria": false,
"maxExtent": 0,
"minExtent": 0,
"ticks": false,
"zindex": 0
},
{
"scale": "y",
"orient": "left",
"gridScale": "x",
"grid": true,
"tickCount": {"signal": "ceil(height/40)"},
"domain": false,
"labels": false,
"aria": false,
"maxExtent": 0,
"minExtent": 0,
"ticks": false,
"zindex": 0
},
{
"scale": "x",
"orient": "bottom",
"grid": false,
"title": "points.x",
"labelFlush": true,
"labelOverlap": true,
"tickCount": {"signal": "ceil(width/40)"},
"zindex": 0
},
{
"scale": "y",
"orient": "left",
"grid": false,
"title": "points.y",
"labelOverlap": true,
"tickCount": {"signal": "ceil(height/40)"},
"zindex": 0
}
],
"legends": [
{
"stroke": "color",
"symbolType": "stroke",
"title": "group",
"encode": {
"labels": {
"name": "group_legend_labels",
"interactive": true,
"update": {
"opacity": [
{
"test": "(!length(data(\"selection_store\")) || (selection[\"group\"] && indexof(selection[\"group\"], datum.value) >= 0))",
"value": 1
},
{"value": 0.35}
]
}
},
"symbols": {
"name": "group_legend_symbols",
"interactive": true,
"update": {
"opacity": [
{
"test": "(!length(data(\"selection_store\")) || (selection[\"group\"] && indexof(selection[\"group\"], datum.value) >= 0))",
"value": 1
},
{"value": 0.35}
]
}
},
"entries": {
"name": "group_legend_entries",
"interactive": true,
"update": {"fill": {"value": "transparent"}}
}
}
}
]
}