diff --git a/src/util/qpolygon-utils.js b/src/util/qpolygon-utils.js
index c2c73775..9fdd7275 100644
--- a/src/util/qpolygon-utils.js
+++ b/src/util/qpolygon-utils.js
@@ -23,8 +23,12 @@ export const defineQPloygon = () => {
  * @returns {number}
  */
 export const calculateAngle = (point1, point2) => {
-  const deltaX = Big(point2.x).minus(point1.x).toNumber()
-  const deltaY = Big(point2.y).minus(point1.y).toNumber()
+  const deltaX = Big(point2?.x !== undefined ? point2.x : 0)
+    .minus(point1?.x !== undefined ? point1.x : 0)
+    .toNumber()
+  const deltaY = Big(point2?.y !== undefined ? point2.y : 0)
+    .minus(point1?.y !== undefined ? point1.y : 0)
+    .toNumber()
   const angleInRadians = Math.atan2(deltaY, deltaX)
   return angleInRadians * (180 / Math.PI)
 }