Fix printing circles

CHANGES.md

@@ -1,4 +1,12 @@
-# @geoblocks/mapfisprint changes
+# @geoblocks/mapfishprint changes
+
+## 0.2.23
+
+- Resolve a bug where a style with its own geometry as a Circle was transformed into a GeometryCollection resulting in an error
+
+Breaking changes:
+
+- VectorEncoder.featureCircleAsPolygon() was removed.
 
 ## 0.2.20
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@geoblocks/mapfishprint",
-  "version": "0.2.22",
+  "version": "0.2.23",
   "publishConfig": {
     "access": "public"
   },

src/VectorEncoder.ts

@@ -167,8 +167,10 @@ export default class VectorEncoder {
     if (styleFunction) {
       styleData = styleFunction(feature, resolution) as null | Style | Style[];
     }
-    if (feature.getGeometry().getType() === 'Circle') {
-      feature = this.featureCircleAsPolygon(feature as Feature<Circle>);
+
+    const featureGeometry = feature.getGeometry();
+    if (featureGeometry.getType() === "Circle") {
+      feature.setGeometry(fromCircle(featureGeometry as Circle, Constants.CIRCLE_TO_POLYGON_SIDES));
     }
     const origGeojsonFeature = this.geojsonFormat.writeFeatureObject(feature);
 
@@ -186,25 +188,30 @@ export default class VectorEncoder {
       // FIXME: the return of the function is very complicate and would require
       // handling more cases than we actually do
       let geometry: any = style.getGeometry();
-      let geojsonFeature;
+      // Fallback to the feature geometry if style doesn't give one.
+      if (geometry === null) {
+        geometry = featureGeometry;
+      }
       // In some cases, the geometries are objects, in other cases they're functions.
       // we need to ensure we're handling functions, wether they return an object or not.
       if (typeof geometry === 'function') {
         geometry = geometry(feature);
       }
-      if (geometry && typeof geometry === 'object') {
+      // no need to encode features with no geometry
+      if (!geometry) return;
+
+      if (geometry.getType() === "Circle") {
+        geometry = fromCircle(geometry as Circle, Constants.CIRCLE_TO_POLYGON_SIDES);
+      }
+      let geojsonFeature;
+      if (typeof geometry === 'object') {
         // note that (typeof null === 'object')
         const styledFeature = feature.clone();
         styledFeature.setGeometry(geometry);
         geojsonFeature = this.geojsonFormat.writeFeatureObject(styledFeature);
         geojsonFeatures.push(geojsonFeature);
       } else {
         geojsonFeature = origGeojsonFeature;
-        geometry = feature.getGeometry();
-        // no need to encode features with no geometry
-        if (!geometry) {
-          return;
-        }
         if (!this.customizer_.geometryFilter(geometry)) {
           return;
         }
@@ -598,15 +605,4 @@ export default class VectorEncoder {
       symbolizers.push(symbolizer);
     }
   }
-
-  /**
-   * Converts a circle feature to a N sides polygon feature.
-   * Sides are defined in Constants.CIRCLE_TO_POLYGON_SIDES.
-   */
-  protected featureCircleAsPolygon(feature: Feature<Circle>) {
-    return new Feature({
-      ...feature.getProperties(),
-      geometry: fromCircle(feature.getGeometry(), Constants.CIRCLE_TO_POLYGON_SIDES),
-    });
-  }
 }

test.js

@@ -1,7 +1,7 @@
 import test from 'node:test';
 import assert from 'node:assert';
 import Map from 'ol/Map.js';
-import {MFPEncoder, BaseCustomizer} from './lib/index.js';
+import {MFPEncoder, MFPVectorEncoder, BaseCustomizer} from './lib/index.js';
 import TileLayer from 'ol/layer/Tile.js';
 import OSM from 'ol/source/OSM.js';
 import {View} from 'ol';
@@ -324,3 +324,46 @@ test('Vector features', async (t) => {
     },
   });
 });
+
+test('MFPVectorEncoder can encode a circle with a circle in its style.geometry', async (t) => {
+  const geomStyleFn = () => {
+    return new Style({
+      geometry: fCircle.getGeometry(),
+      fill,
+      stroke
+    });
+  };
+  fCircle.setStyle(geomStyleFn);
+  const vectorLayer = new VectorLayer({
+    source: new VectorSource({
+      features: [fCircle],
+    }),
+  });
+  const customizer = new BaseCustomizer();
+  const resolution = 1.0583354500042335;
+  const encodedSpecialLayer = new MFPVectorEncoder(vectorLayer.getLayerState(), customizer).encodeVectorLayer(resolution);
+
+  assert.deepEqual(encodedSpecialLayer.geoJson.features[0], {
+    type: 'Feature',
+    geometry: {
+      type: 'Polygon',
+      coordinates: [
+        [
+          [796622, 5836960],
+          [796619.0710678119, 5836967.071067812],
+          [796612, 5836970],
+          [796604.9289321881, 5836967.071067812],
+          [796602, 5836960],
+          [796604.9289321881, 5836952.928932188],
+          [796612, 5836950],
+          [796619.0710678119, 5836952.928932188],
+          [796622, 5836960],
+        ],
+      ],
+    },
+    properties: {
+      name: 'A circle',
+      _mfp_style: '1',
+    },
+  });
+});