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\u65cb\u8f6c\u524d\u5750\u6807\nconst diffXAfter = x - centerX;     \/\/ \u65cb\u8f6c\u540e\u5750\u6807\nconst diffYAfter = y - centerY;     \/\/ \u65cb\u8f6c\u540e\u5750\u6807\n\nconst angleBefore = Math.atan2(diffYBefore, diffXBefore) \/ Math.PI * 180;\nconst angleAfter = Math.atan2(diffYAfter, diffXAfter) \/ Math.PI * 180;\n\n\/\/ \u65cb\u8f6c\u7684\u89d2\u5ea6\nthis.rotate = currentGraph.rotate + angleAfter - angleBefore;<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u8ba1\u7b97\u7f29\u653e\u5c3a\u5bf8\u7684\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n<pre>\/\/ \u653e\u5927 \u6216 \u7f29\u5c0f\nthis.x = currentGraph.x - (x - px);\nthis.y = currentGraph.y - (x - px);<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>&nbsp; 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