feat: add pointer move event (#128)

src/events.js

@@ -20,6 +20,8 @@ const EVENTS = {
   ROI_SELECTED: `${PROJECT_NAME}_roi_selected`,
   /** Triggered when a ROI was double clicked. */
   ROI_DOUBLE_CLICKED: `${PROJECT_NAME}_roi_double_clicked`,
+  /** Triggered when mouse moves. */
+  POINTER_MOVE: `${PROJECT_NAME}_pointer_move`,
   /** Triggered when a ROI was modified. */
   ROI_MODIFIED: `${PROJECT_NAME}_roi_modified`,
   /** Triggered when a viewport move has started. */

src/viewer.js

@@ -1540,6 +1540,32 @@ class VolumeImageViewer {
     })
 
     let clickEvent = null
+
+    this[_map].on("pointermove", (event) => {
+      let featureCounter = 0;
+      this[_map].forEachFeatureAtPixel(event.pixel, (feature) => {
+        const correctFeature = feature.values_?.features?.[0] || feature;
+        console.debug("pointermove feature id:", correctFeature);
+        if (correctFeature?.getId()) {
+          featureCounter++;
+          publish(this[_map].getTargetElement(), EVENT.POINTER_MOVE, {
+            feature: this._getROIFromFeature(
+              correctFeature,
+              this[_pyramid].metadata,
+              this[_affine]
+            ),
+            event,
+          });
+        }
+      });
+      if (!featureCounter) {
+        publish(this[_map].getTargetElement(), EVENT.POINTER_MOVE, {
+          feature: null,
+          event,
+        });
+      }
+    });
+
     this[_map].on('dblclick', (event) => {
       if (this[_interactions].draw !== undefined) {
         return