Change the default for "resolve" to "shared"

build/vega-lite-schema.json

@@ -8144,7 +8144,7 @@
           "type": "number"
         },
         "resolve": {
-          "description": "Indicates how parameters for multiple densities should be resolved. If `\"independent\"`, each density may have its own domain extent and dynamic number of curve sample steps. If `\"shared\"`, the KDE transform will ensure that all densities are defined over a shared domain and curve steps, enabling stacking.\n\n__Default value:__ `\"independent\"`",
+          "description": "Indicates how parameters for multiple densities should be resolved. If \"independent\", each density may have its own domain extent and dynamic number of curve sample steps. If \"shared\", the KDE transform will ensure that all densities are defined over a shared domain and curve steps, enabling stacking.\n\n__Default value:__ `\"shared\"`",
           "enum": [
             "independent",
             "shared"

examples/compiled/area_density.vg.json

@@ -16,7 +16,7 @@
           "field": "IMDB Rating",
           "bandwidth": 0.3,
           "as": ["value", "density"],
-          "resolve": "independent"
+          "resolve": "shared"
         },
         {
           "type": "impute",

examples/compiled/area_density_facet.vg.json

@@ -15,7 +15,7 @@
           "groupby": ["Species"],
           "extent": [2500, 6500],
           "as": ["value", "density"],
-          "resolve": "independent"
+          "resolve": "shared"
         },
         {
           "type": "impute",

examples/compiled/area_density_stacked.vg.json

@@ -18,7 +18,7 @@
           "groupby": ["Species"],
           "extent": [2500, 6500],
           "as": ["value", "density"],
-          "resolve": "independent"
+          "resolve": "shared"
         },
         {
           "type": "impute",

examples/compiled/area_density_stacked_fold.vg.json

@@ -25,7 +25,7 @@
           "counts": true,
           "steps": 200,
           "as": ["value", "density"],
-          "resolve": "independent"
+          "resolve": "shared"
         },
         {
           "type": "impute",

src/compile/data/density.ts

@@ -19,7 +19,7 @@ export class DensityTransformNode extends DataFlowNode {
     this.transform = duplicate(transform); // duplicate to prevent side effects
     const specifiedAs = this.transform.as ?? [undefined, undefined];
     this.transform.as = [specifiedAs[0] ?? 'value', specifiedAs[1] ?? 'density'];
-    const resolve = this.transform.resolve ?? 'independent';
+    const resolve = this.transform.resolve ?? 'shared';
     this.transform.resolve = resolve;
   }
 

src/transform.ts

@@ -501,7 +501,7 @@ export interface DensityTransform {
    * If `"independent"`, each density may have its own domain extent and dynamic number of curve sample steps.
    * If `"shared"`, the KDE transform will ensure that all densities are defined over a shared domain and curve steps, enabling stacking.
    *
-   * __Default value:__ `"independent"`
+   * __Default value:__ `"shared"`
    */
   resolve?: 'independent' | 'shared';
 }

test/compile/data/density.test.ts

@@ -27,7 +27,7 @@ describe('compile/data/fold', () => {
         extent: [0, 10],
         minsteps: 25,
         maxsteps: 200,
-        resolve: 'independent',
+        resolve: 'shared',
         as: ['x', 'y']
       });
     });
@@ -41,7 +41,7 @@ describe('compile/data/fold', () => {
       expect(density.assemble()).toEqual({
         type: 'kde',
         field: 'v',
-        resolve: 'independent',
+        resolve: 'shared',
         as: ['value', 'density']
       });
     });
@@ -55,7 +55,7 @@ describe('compile/data/fold', () => {
       expect(density.assemble()).toEqual({
         type: 'kde',
         field: 'v',
-        resolve: 'independent',
+        resolve: 'shared',
         as: ['A', 'density']
       });
     });
@@ -122,7 +122,7 @@ describe('compile/data/fold', () => {
         as: ['A', 'B']
       };
       const density = new DensityTransformNode(null, transform);
-      expect(density.hash()).toBe('DensityTransform {"as":["A","B"],"density":"v","resolve":"independent"}');
+      expect(density.hash()).toBe('DensityTransform {"as":["A","B"],"density":"v","resolve":"shared"}');
     });
   });