Make a eraser tool

1

hi, i simulate a pencil tool in my application, now i want simulate a eraser tool, but no success. how can i eraser that lines draw by pencil in as 3? i try removeChildAt(0); it work’s but all draw is erased.

i’ll post only the method that selectedTool and how i simulate the pencil


private function selecionarFerramenta(e:MouseEvent):void{
                    
                            switch(e.target.name){
                                
                                case "pencil":
                                trace('pencil selected');
                                removeEventsBorracha();
                                addEventListener(Event.ENTER_FRAME,onLoop);
                                addEventListener(MouseEvent.MOUSE_DOWN , onDown);
                                addEventListener(MouseEvent.MOUSE_UP , onUp);
                                break;
                                
                                case "eraser":
                                trace('eraser selected');
                                break;
                                }
                    
                    }


private function onDown(e:MouseEvent):void{
                        drawing = true;
                        
                    }
    
            private function onUp(e:MouseEvent):void{
                        drawing = false;
                    }
                    
                
            private function onLoop(e:Event):void {
                  if (drawing){
                    
                    g1.lineTo(mouseX, mouseY);
                    
                    
                } else{
                     g1.moveTo(mouseX, mouseY);
                     
                     }
                }

Any sugestions?

Ty