Update app.py

app.py

@@ -377,6 +377,8 @@ with gr.Blocks(css=css) as demo:
                         pl_a[i] = x+\",\"+parseInt(lerp( yold, y, (i-xold)/(x-xold) ));
                       }
                       pl_a[x] = x+\",\"+y;
+                      xold = x;
+                      yold = y;
                       document.getElementById(\"pl\").setAttribute(\"points\", pl_a.join(\" \"));
                     }
                   }
@@ -393,6 +395,8 @@ with gr.Blocks(css=css) as demo:
                   }
                   this.onpointerleave = this.onpointerup;
                 }
+                xold = x;
+                yold = y;
                 this.title = xold+\",\"+yold;
               }catch(e){alert(e);}
               '>