오류 수정

src/hooks/useCanvas.js

@@ -121,6 +121,7 @@ export function useCanvas(id) {
         delete instance.points
         callback && callback(instance)
       }
+
       const options = fabric.util.object.clone(object, true)
       options.points = [object.x1, object.y1, object.x2, object.y2]
 
@@ -526,7 +527,7 @@ export function useCanvas(id) {
       }
     }
 
-    canvas.renderAll()
+    canvas?.renderAll()
   }
 
   const setCanvasBackgroundWithDots = (canvas, gap) => {