fix(draw): render fill as none when fill is transparent #WIK-19978

Author: pubuzhixing8

.changeset/sour-spiders-bow.md

@@ -0,0 +1,5 @@
+---
+'@plait/draw': minor
+---
+
+render fill as none when fill is transparent

packages/draw/src/utils/style/stroke.ts

@@ -3,7 +3,7 @@ import { DefaultDrawStyle } from '../../constants';
 import { PlaitBoard, PlaitElement } from '@plait/core';
 import { getDrawDefaultStrokeColor, getFlowchartDefaultFill } from '../geometry';
 import { isClosedDrawElement } from '../common';
-import { StrokeStyle } from '@plait/common';
+import { StrokeStyle, TRANSPARENT } from '@plait/common';
 
 export const getStrokeColorByElement = (board: PlaitBoard, element: PlaitElement) => {
     const defaultColor = getDrawDefaultStrokeColor(board.theme.themeColorMode);
@@ -16,7 +16,9 @@ export const getFillByElement = (board: PlaitBoard, element: PlaitElement) => {
         PlaitDrawElement.isFlowchart(element) && isClosedDrawElement(element as PlaitDrawElement)
             ? getFlowchartDefaultFill(board.theme.themeColorMode)
             : DefaultDrawStyle.fill;
-    const fill = element.fill || defaultFill;
+    const currentFill =
+        element.fill && (element.fill === TRANSPARENT || element.fill === TRANSPARENT.toUpperCase()) ? DefaultDrawStyle.fill : element.fill;
+    const fill = currentFill || defaultFill;
     return fill;
 };