添加一个查找对面玩家的方法

src/global.d.ts

@@ -260,6 +260,11 @@ declare module "colyseus" {
          */
         getAssistClient(sessionId: string): RobotClient;
 
+        /**
+         * 获取对位玩家
+         * @param srcPlayer
+         */
+        getOppositePlayer(srcPlayer: string|Player): Player;
     }
 }
 

src/rooms/GeneralRoom.ts

@@ -282,4 +282,20 @@ export class GeneralRoom extends Room {
   getAssistClient(sessionId: string): RobotClient {
     return this.assistMap.get(sessionId);
   }
+
+  getOppositePlayer(srcPlayer: string | Player): Player {
+    let playerId;
+    if (typeof srcPlayer === 'string') {
+      playerId = srcPlayer as string;
+    } else {
+      playerId = srcPlayer.id;
+    }
+    if (!this.state.players.has(playerId)) {
+      return null;
+    }
+    const sessionIds = [...this.state.players.keys()];
+    let idx = sessionIds.indexOf(playerId);
+    let playerId2 = sessionIds[(2 + idx) % 4];
+    return this.state.players.get(playerId2);
+  }
 }