feat: tooltip position

utils/common.js

@@ -240,10 +240,30 @@ const install = (Vue, vm) => {
 	const dealTooltip = (tooltip) => {
 		if (!tooltip) {
 			return
-		}
+		}
+		tooltip = {
+			...tooltip,
+			position(point, params, dom, rect, size) {
+			  let x = point[0];
+				let y = point[1];
+			  const { contentSize, viewSize } = size;
+			  const maxX = viewSize[0] - contentSize[0];
+			  if (x > maxX) {
+					x -= contentSize[0];
+			  }
+				const maxY = viewSize[1] - contentSize[1];
+				if (y > maxY) {
+					y -= contentSize[1];
+				}
+				if(y < 0) {
+					y = 0
+				}
+			  return [x, y];
+			}
+		}
 		if (tooltip.formatter && tooltip.formatter.length) {
 			return {
-				...tooltip,
+				...tooltip,
 				formatter: (val) => {
 					return converFunction(tooltip.formatter, val)
 				},