Handle area and length calc exceptions (#61)

Author: igoroctaviano

src/annotations/markups/measurement.js

@@ -13,9 +13,9 @@ import {
  * @return {string} The formatted measure of this feature
  */
 export const format = (feature, units, pyramid) => {
-  const length = getFeatureScoord3dLength(feature, pyramid)
   const area = getFeatureScoord3dArea(feature, pyramid)
-  const value = length || area
+  const length = getFeatureScoord3dLength(feature, pyramid)
+  const value = length || area || 0
   return length
     ? `${value.toFixed(2)} ${units}`
     : `${value.toFixed(2)} ${units}²`

src/scoord3dUtils.js

@@ -375,11 +375,6 @@ function getFeatureScoord3dLength (feature, pyramid) {
     } else {
       throw new Error('ROI does not have any coordinates.')
     }
-  } else {
-    throw new Error(
-      'Calculation of length is only supported for ROIs with spatial ' +
-      'coordinates of graphic type POLYLINE.'
-    )
   }
 }
 

src/viewer.js

@@ -337,7 +337,9 @@ function _updateFeatureMeasurements (map, feature, pyramid) {
   const area = getFeatureScoord3dArea(feature, pyramid)
   const length = getFeatureScoord3dLength(feature, pyramid)
 
-  if (!area && !length) return
+  if (area == null && length == null) {
+    return
+  }
 
   const unitSuffixToMeaningMap = {
     μm: 'micrometer',