diff --git a/src/modules/heightmap-generator.ts b/src/modules/heightmap-generator.ts
index eb48f9f4..27fb063b 100644
--- a/src/modules/heightmap-generator.ts
+++ b/src/modules/heightmap-generator.ts
@@ -560,9 +560,7 @@ class HeightmapGenerator {
         if(!ctx) {
           throw new Error("Could not get canvas context");
         }
-        if(!this.heights) {
-          throw new Error("Heights array is not initialized");
-        }
+        this.heights = this.heights || new Uint8Array(cellsX * cellsY);
         ctx.drawImage(img, 0, 0, cellsX, cellsY);
         const imageData = ctx.getImageData(0, 0, cellsX, cellsY);
         this.setGraph(graph);
diff --git a/src/utils/stringUtils.ts b/src/utils/stringUtils.ts
index 02c4d42a..dc00a23a 100644
--- a/src/utils/stringUtils.ts
+++ b/src/utils/stringUtils.ts
@@ -6,7 +6,7 @@ import { rn } from "./numberUtils";
  * @param {number} decimals - Number of decimal places (default is 1)
  * @returns {string} - The string with rounded numbers
  */
-export const round = (inputString: string, decimals: number = 1) => {
+export const round = (inputString: string = "", decimals: number = 1) => {
   return inputString.replace(/[\d\.-][\d\.e-]*/g, (n: string) => {
     return rn(parseFloat(n), decimals).toString();
   });