feat: Region/Lasso Selections

build/vega-lite-schema.json

@@ -20731,6 +20731,106 @@
       },
       "type": "object"
     },
+    "RegionSelectionConfig": {
+      "additionalProperties": false,
+      "properties": {
+        "clear": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/Stream"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "type": "boolean"
+            }
+          ],
+          "description": "Clears the selection, emptying it of all values. This property can be a [Event Stream](https://vega.github.io/vega/docs/event-streams/) or `false` to disable clear.\n\n__Default value:__ `dblclick`.\n\n__See also:__ [`clear` examples ](https://vega.github.io/vega-lite/docs/selection.html#clear) in the documentation."
+        },
+        "encodings": {
+          "description": "An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.\n\n__See also:__ The [projection with `encodings` and `fields` section](https://vega.github.io/vega-lite/docs/selection.html#project) in the documentation.",
+          "items": {
+            "$ref": "#/definitions/SingleDefUnitChannel"
+          },
+          "type": "array"
+        },
+        "mark": {
+          "$ref": "#/definitions/BrushConfig",
+          "description": "A region selection also adds a path mark to depict the shape of the region. The `mark` property can be used to customize the appearance of the mark.\n\n__See also:__ [`mark` examples](https://vega.github.io/vega-lite/docs/selection.html#mark) in the documentation."
+        },
+        "on": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/Stream"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "description": "A [Vega event stream](https://vega.github.io/vega/docs/event-streams/) (object or selector) that triggers the selection. For interval selections, the event stream must specify a [start and end](https://vega.github.io/vega/docs/event-streams/#between-filters).\n\n__See also:__ [`on` examples](https://vega.github.io/vega-lite/docs/selection.html#on) in the documentation."
+        },
+        "resolve": {
+          "$ref": "#/definitions/SelectionResolution",
+          "description": "With layered and multi-view displays, a strategy that determines how selections' data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.\n\nOne of:\n- `\"global\"` -- only one brush exists for the entire SPLOM. When the user begins to drag, any previous brushes are cleared, and a new one is constructed.\n- `\"union\"` -- each cell contains its own brush, and points are highlighted if they lie within _any_ of these individual brushes.\n- `\"intersect\"` -- each cell contains its own brush, and points are highlighted only if they fall within _all_ of these individual brushes.\n\n__Default value:__ `global`.\n\n__See also:__ [`resolve` examples](https://vega.github.io/vega-lite/docs/selection.html#resolve) in the documentation."
+        },
+        "type": {
+          "const": "region",
+          "description": "Determines the default event processing and data query for the selection. Vega-Lite currently supports two selection types:\n\n- `\"point\"` -- to select multiple discrete data values; the first value is selected on `click` and additional values toggled on shift-click.\n- `\"interval\"` -- to select a continuous range of data values on `drag`.",
+          "type": "string"
+        }
+      },
+      "required": [
+        "type"
+      ],
+      "type": "object"
+    },
+    "RegionSelectionConfigWithoutType": {
+      "additionalProperties": false,
+      "properties": {
+        "clear": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/Stream"
+            },
+            {
+              "type": "string"
+            },
+            {
+              "type": "boolean"
+            }
+          ],
+          "description": "Clears the selection, emptying it of all values. This property can be a [Event Stream](https://vega.github.io/vega/docs/event-streams/) or `false` to disable clear.\n\n__Default value:__ `dblclick`.\n\n__See also:__ [`clear` examples ](https://vega.github.io/vega-lite/docs/selection.html#clear) in the documentation."
+        },
+        "encodings": {
+          "description": "An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.\n\n__See also:__ The [projection with `encodings` and `fields` section](https://vega.github.io/vega-lite/docs/selection.html#project) in the documentation.",
+          "items": {
+            "$ref": "#/definitions/SingleDefUnitChannel"
+          },
+          "type": "array"
+        },
+        "mark": {
+          "$ref": "#/definitions/BrushConfig",
+          "description": "A region selection also adds a path mark to depict the shape of the region. The `mark` property can be used to customize the appearance of the mark.\n\n__See also:__ [`mark` examples](https://vega.github.io/vega-lite/docs/selection.html#mark) in the documentation."
+        },
+        "on": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/Stream"
+            },
+            {
+              "type": "string"
+            }
+          ],
+          "description": "A [Vega event stream](https://vega.github.io/vega/docs/event-streams/) (object or selector) that triggers the selection. For interval selections, the event stream must specify a [start and end](https://vega.github.io/vega/docs/event-streams/#between-filters).\n\n__See also:__ [`on` examples](https://vega.github.io/vega-lite/docs/selection.html#on) in the documentation."
+        },
+        "resolve": {
+          "$ref": "#/definitions/SelectionResolution",
+          "description": "With layered and multi-view displays, a strategy that determines how selections' data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.\n\nOne of:\n- `\"global\"` -- only one brush exists for the entire SPLOM. When the user begins to drag, any previous brushes are cleared, and a new one is constructed.\n- `\"union\"` -- each cell contains its own brush, and points are highlighted if they lie within _any_ of these individual brushes.\n- `\"intersect\"` -- each cell contains its own brush, and points are highlighted only if they fall within _all_ of these individual brushes.\n\n__Default value:__ `global`.\n\n__See also:__ [`resolve` examples](https://vega.github.io/vega-lite/docs/selection.html#resolve) in the documentation."
+        }
+      },
+      "type": "object"
+    },
     "RegressionTransform": {
       "additionalProperties": false,
       "properties": {
@@ -21949,6 +22049,10 @@
         "point": {
           "$ref": "#/definitions/PointSelectionConfigWithoutType",
           "description": "The default definition for a [`point`](https://vega.github.io/vega-lite/docs/parameter.html#select) selection. All properties and transformations  for a point selection definition (except `type`) may be specified here.\n\nFor instance, setting `point` to `{\"on\": \"dblclick\"}` populates point selections on double-click by default."
+        },
+        "region": {
+          "$ref": "#/definitions/RegionSelectionConfigWithoutType",
+          "description": "The default definition for an [`region`](https://vega.github.io/vega-lite/docs/parameter.html#select) selection. All properties and transformations for an region selection definition (except `type`) may be specified here."
         }
       },
       "type": "object"
@@ -22023,6 +22127,9 @@
             },
             {
               "$ref": "#/definitions/IntervalSelectionConfig"
+            },
+            {
+              "$ref": "#/definitions/RegionSelectionConfig"
             }
           ],
           "description": "Determines the default event processing and data query for the selection. Vega-Lite currently supports two selection types:\n\n- `\"point\"` -- to select multiple discrete data values; the first value is selected on `click` and additional values toggled on shift-click.\n- `\"interval\"` -- to select a continuous range of data values on `drag`."
@@ -22062,7 +22169,8 @@
     "SelectionType": {
       "enum": [
         "point",
-        "interval"
+        "interval",
+        "region"
       ],
       "type": "string"
     },
@@ -29483,6 +29591,9 @@
             },
             {
               "$ref": "#/definitions/IntervalSelectionConfig"
+            },
+            {
+              "$ref": "#/definitions/RegionSelectionConfig"
             }
           ],
           "description": "Determines the default event processing and data query for the selection. Vega-Lite currently supports two selection types:\n\n- `\"point\"` -- to select multiple discrete data values; the first value is selected on `click` and additional values toggled on shift-click.\n- `\"interval\"` -- to select a continuous range of data values on `drag`."

examples/compiled/selection_type_region.vg.json

@@ -0,0 +1,220 @@
+{
+  "$schema": "https://vega.github.io/schema/vega/v5.json",
+  "background": "white",
+  "padding": 5,
+  "width": 200,
+  "height": 200,
+  "style": "cell",
+  "data": [
+    {
+      "name": "brush_store",
+      "transform": [{"type": "collect", "sort": {"field": "_vgsid_"}}]
+    },
+    {
+      "name": "source_0",
+      "url": "data/cars.json",
+      "format": {"type": "json"},
+      "transform": [
+        {"type": "identifier", "as": "_vgsid_"},
+        {
+          "type": "filter",
+          "expr": "isValid(datum[\"Horsepower\"]) && isFinite(+datum[\"Horsepower\"]) && isValid(datum[\"Miles_per_Gallon\"]) && isFinite(+datum[\"Miles_per_Gallon\"])"
+        }
+      ]
+    }
+  ],
+  "signals": [
+    {
+      "name": "unit",
+      "value": {},
+      "on": [
+        {"events": "mousemove", "update": "isTuple(group()) ? group() : unit"}
+      ]
+    },
+    {
+      "name": "brush",
+      "update": "vlSelectionResolve(\"brush_store\", \"union\")"
+    },
+    {
+      "name": "brush_tuple",
+      "on": [
+        {
+          "events": [{"signal": "brush_screen_path"}],
+          "update": "vlSelectionTuples(intersectLasso(\"marks\", brush_screen_path, unit), {unit: \"\"})"
+        },
+        {"events": [{"source": "view", "type": "dblclick"}], "update": "null"}
+      ]
+    },
+    {
+      "name": "brush_screen_path",
+      "init": "[]",
+      "on": [
+        {
+          "events": {"source": "scope", "type": "mousedown"},
+          "update": "[[x(unit), y(unit)]]"
+        },
+        {
+          "events": {
+            "source": "window",
+            "type": "mousemove",
+            "consume": true,
+            "between": [
+              {"source": "scope", "type": "mousedown"},
+              {"source": "window", "type": "mouseup"}
+            ]
+          },
+          "update": "lassoAppend(brush_screen_path, clamp(x(unit), 0, width), clamp(y(unit), 0, height))"
+        }
+      ]
+    },
+    {
+      "name": "brush_modify",
+      "on": [
+        {
+          "events": {"signal": "brush_tuple"},
+          "update": "modify(\"brush_store\", brush_tuple, true)"
+        }
+      ]
+    }
+  ],
+  "marks": [
+    {
+      "name": "brush_brush",
+      "type": "path",
+      "encode": {
+        "enter": {
+          "fill": {"value": "#333"},
+          "fillOpacity": {"value": 0.125},
+          "stroke": {"value": "gray"},
+          "strokeWidth": {"value": 2},
+          "strokeDash": {"value": [8, 5]}
+        },
+        "update": {
+          "path": [
+            {
+              "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"\"",
+              "signal": "lassoPath(brush_screen_path)"
+            },
+            {"value": "[]"}
+          ]
+        }
+      }
+    },
+    {
+      "name": "marks",
+      "type": "symbol",
+      "style": ["point"],
+      "interactive": true,
+      "from": {"data": "source_0"},
+      "encode": {
+        "update": {
+          "opacity": {"value": 0.7},
+          "fill": {"value": "transparent"},
+          "stroke": [
+            {
+              "test": "!length(data(\"brush_store\")) || vlSelectionIdTest(\"brush_store\", datum)",
+              "scale": "color",
+              "field": "Cylinders"
+            },
+            {"value": "grey"}
+          ],
+          "ariaRoleDescription": {"value": "point"},
+          "description": {
+            "signal": "\"Horsepower: \" + (format(datum[\"Horsepower\"], \"\")) + \"; Miles_per_Gallon: \" + (format(datum[\"Miles_per_Gallon\"], \"\")) + \"; Cylinders: \" + (isValid(datum[\"Cylinders\"]) ? datum[\"Cylinders\"] : \"\"+datum[\"Cylinders\"])"
+          },
+          "x": {"scale": "x", "field": "Horsepower"},
+          "y": {"scale": "y", "field": "Miles_per_Gallon"}
+        }
+      }
+    }
+  ],
+  "scales": [
+    {
+      "name": "x",
+      "type": "linear",
+      "domain": {"data": "source_0", "field": "Horsepower"},
+      "range": [0, {"signal": "width"}],
+      "nice": true,
+      "zero": true
+    },
+    {
+      "name": "y",
+      "type": "linear",
+      "domain": {"data": "source_0", "field": "Miles_per_Gallon"},
+      "range": [{"signal": "height"}, 0],
+      "nice": true,
+      "zero": true
+    },
+    {
+      "name": "color",
+      "type": "ordinal",
+      "domain": {"data": "source_0", "field": "Cylinders", "sort": true},
+      "range": "ordinal",
+      "interpolate": "hcl"
+    }
+  ],
+  "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": "Horsepower",
+      "labelFlush": true,
+      "labelOverlap": true,
+      "tickCount": {"signal": "ceil(width/40)"},
+      "zindex": 0
+    },
+    {
+      "scale": "y",
+      "orient": "left",
+      "grid": false,
+      "title": "Miles_per_Gallon",
+      "labelOverlap": true,
+      "tickCount": {"signal": "ceil(height/40)"},
+      "zindex": 0
+    }
+  ],
+  "legends": [
+    {
+      "stroke": "color",
+      "symbolType": "circle",
+      "title": "Cylinders",
+      "encode": {
+        "symbols": {
+          "update": {
+            "fill": {"value": "transparent"},
+            "opacity": {"value": 0.7}
+          }
+        }
+      }
+    }
+  ]
+}