fix zero ratio issue

Author: sulincix

src/widgets/DrawingWidget.cpp

@@ -496,6 +496,7 @@ int DrawingWidget::getLineStyle(){
 
 static int num_of_press = 0;
 void DrawingWidget::eventHandler(int source, int type, int id, QPointF pos, float pressure){
+    //printf("%d %d %d\n", source, type, id);
     int ev_pen = penType;
     if(source & Qt::MiddleButton) {
         penType = MARKER;

src/widgets/WhiteBoard.cpp

@@ -111,6 +111,10 @@ void WhiteBoard::paintEvent(QPaintEvent *event) {
     );
 
 
+    if (!ratios.contains(drawing->getPageNum())
+        || ratios[drawing->getPageNum()] <= 0){
+        ratios[drawing->getPageNum()] = 100.0;
+    }
     float ratio = ratios[drawing->getPageNum()] / 100.0;