fix(bugs): enhancements and bugs in several areas (#4086)

extensions/cornerstone/src/Viewport/Overlays/CustomizableViewportOverlay.tsx

@@ -137,20 +137,8 @@ function CustomizableViewportOverlay({
           return;
         }
 
-        const imageData = viewport.getImageData();
+        const scale = viewport.getZoom();
 
-        if (!imageData) {
-          return;
-        }
-
-        if (camera.scale) {
-          setScale(camera.scale);
-          return;
-        }
-
-        const { spacing } = imageData;
-        // convert parallel scale to scale
-        const scale = (element.clientHeight * spacing[0] * 0.5) / camera.parallelScale;
         setScale(scale);
       }
     };

extensions/cornerstone/src/services/SegmentationService/SegmentationService.ts

@@ -568,7 +568,7 @@ class SegmentationService extends PubSubService {
         rgba,
       } = segmentInfo;
 
-      const { x, y, z } = segDisplaySet.centroids.get(segmentIndex);
+      const { x, y, z } = segDisplaySet.centroids.get(segmentIndex) || { x: 0, y: 0, z: 0 };
       const centerWorld = derivedVolume.imageData.indexToWorld([x, y, z]);
 
       segmentation.cachedStats = {