fix brush drawing glitch v2

src/regions/BrushRegion.js

@@ -480,7 +480,7 @@ const HtxBrushView = ({ item }) => {
         onDraw={() => {
           setTimeout(drawCallback);
         }}
-        clearBeforeDraw={!item.parent?.isDrawing}
+        clearBeforeDraw={!item.isDrawing}
       >
         <Group
           attrMy={item.needsUpdate}

src/tools/Brush.js

@@ -162,6 +162,7 @@ const _Tool = types
         brush = self.getSelectedShape;
         if (brush && brush.type === "brushregion") {
           self.mode = "drawing";
+          brush.setDrawing(true);
           isFirstBrushStroke = false;
           brush.beginPath({
             type: "add",