fix(symbol): fix `symbolOffset` bug in `effectSymbol`.

src/chart/helper/EffectSymbol.ts

@@ -184,11 +184,15 @@ class EffectSymbol extends Group {
             ripplePath.setStyle('fill', color);
         });
 
-        const symbolOffset = itemModel.getShallow('symbolOffset');
+        let symbolOffset = data.getItemVisual(idx, 'symbolOffset');
         if (symbolOffset) {
+            if (!zrUtil.isArray(symbolOffset)) {
+                symbolOffset = [symbolOffset, symbolOffset];
+            }
             rippleGroup.x = parsePercent(symbolOffset[0], symbolSize[0]);
-            rippleGroup.y = parsePercent(symbolOffset[1], symbolSize[1]);
+            rippleGroup.y = parsePercent(zrUtil.retrieve2(symbolOffset[1], symbolOffset[0]) || 0, symbolSize[1]);
         }
+
         const symbolRotate = data.getItemVisual(idx, 'symbolRotate');
         rippleGroup.rotation = (symbolRotate || 0) * Math.PI / 180 || 0;
 
@@ -247,4 +251,4 @@ class EffectSymbol extends Group {
 }
 zrUtil.inherits(EffectSymbol, Group);
 
-export default EffectSymbol;
\ No newline at end of file
+export default EffectSymbol;

src/chart/helper/Symbol.ts

@@ -256,13 +256,14 @@ class Symbol extends graphic.Group {
         symbolPath.attr('rotation', (symbolRotate || 0) * Math.PI / 180 || 0);
 
         let symbolOffset = data.getItemVisual(idx, 'symbolOffset') || 0;
-        if (!isArray(symbolOffset)) {
-            symbolOffset = [symbolOffset, symbolOffset];
+        if (symbolOffset) {
+            if (!isArray(symbolOffset)) {
+                symbolOffset = [symbolOffset, symbolOffset];
+            }
+            symbolPath.x = parsePercent(symbolOffset[0], symbolSize[0]);
+            symbolPath.y = parsePercent(retrieve2(symbolOffset[1], symbolOffset[0]) || 0, symbolSize[1]);
         }
 
-        symbolPath.x = parsePercent(symbolOffset[0], symbolSize[0]);
-        symbolPath.y = parsePercent(retrieve2(symbolOffset[1], symbolOffset[0]) || 0, symbolSize[1]);
-
         cursorStyle && symbolPath.attr('cursor', cursorStyle);
 
         const symbolStyle = data.getItemVisual(idx, 'style');