From ab6a04693d99125c4caeddbb2532d97324cf0adf Mon Sep 17 00:00:00 2001
From: genxium <genxium@hotmail.com>
Date: Thu, 5 Jan 2023 12:14:55 +0800
Subject: [PATCH] Enhanced backend input prediction alignment with the frontend
 counterpart.

---
 battle_srv/models/player.go       |  7 ++++---
 battle_srv/models/room.go         | 23 +++++++++++++----------
 frontend/assets/scenes/login.fire |  2 +-
 frontend/assets/scripts/Map.js    |  8 --------
 4 files changed, 18 insertions(+), 22 deletions(-)

diff --git a/battle_srv/models/player.go b/battle_srv/models/player.go
index 11fe20e..6ec281b 100644
--- a/battle_srv/models/player.go
+++ b/battle_srv/models/player.go
@@ -46,9 +46,10 @@ type Player struct {
 	TutorialStage int       `db:"tutorial_stage"`
 
 	// other in-battle info fields
-	LastSentInputFrameId int32
-	AckingFrameId        int32
-	AckingInputFrameId   int32
+	LastReceivedInputFrameId int32
+	LastSentInputFrameId     int32
+	AckingFrameId            int32
+	AckingInputFrameId       int32
 }
 
 func ExistPlayerByName(name string) (bool, error) {
diff --git a/battle_srv/models/room.go b/battle_srv/models/room.go
index 0cc7ac3..4b3039e 100644
--- a/battle_srv/models/room.go
+++ b/battle_srv/models/room.go
@@ -172,6 +172,7 @@ func (pR *Room) AddPlayerIfPossible(pPlayerFromDbInit *Player, session *websocke
 	pPlayerFromDbInit.AckingFrameId = -1
 	pPlayerFromDbInit.AckingInputFrameId = -1
 	pPlayerFromDbInit.LastSentInputFrameId = MAGIC_LAST_SENT_INPUT_FRAME_ID_NORMAL_ADDED
+	pPlayerFromDbInit.LastReceivedInputFrameId = MAGIC_LAST_SENT_INPUT_FRAME_ID_NORMAL_ADDED
 	pPlayerFromDbInit.BattleState = PlayerBattleStateIns.ADDED_PENDING_BATTLE_COLLIDER_ACK
 
 	pPlayerFromDbInit.ColliderRadius = DEFAULT_PLAYER_RADIUS // Hardcoded
@@ -1033,16 +1034,16 @@ func (pR *Room) getOrPrefabInputFrameDownsync(inputFrameId int32) *battle.InputF
 				ConfirmedList: uint64(0),
 			}
 
-			j2 := j - 1
-			tmp2 := pR.InputsBuffer.GetByFrameId(j2)
-			if nil != tmp2 {
-				prevInputFrameDownsync := tmp2.(*battle.InputFrameDownsync)
-				for i, _ := range currInputFrameDownsync.InputList {
+			for i, _ := range currInputFrameDownsync.InputList {
+				j2 := pR.PlayersArr[i].LastReceivedInputFrameId
+				if j2 < pR.InputsBuffer.StFrameId {
+					j2 = pR.InputsBuffer.StFrameId
+				}
+				tmp2 := pR.InputsBuffer.GetByFrameId(j2)
+				if nil != tmp2 {
+					prevInputFrameDownsync := tmp2.(*battle.InputFrameDownsync)
 					currInputFrameDownsync.InputList[i] = prevInputFrameDownsync.InputList[i]
 				}
-			}
-
-			for i, _ := range currInputFrameDownsync.InputList {
 				// Don't predict "btnA & btnB"!
 				currInputFrameDownsync.InputList[i] = (currInputFrameDownsync.InputList[i] & uint64(15))
 			}
@@ -1066,8 +1067,8 @@ func (pR *Room) markConfirmationIfApplicable(inputFrameUpsyncBatch []*pb.InputFr
 			Logger.Debug(fmt.Sprintf("Omitting obsolete inputFrameUpsync#1: roomId=%v, playerId=%v, clientInputFrameId=%v, InputsBuffer=%v", pR.Id, playerId, clientInputFrameId, pR.InputsBufferString(false)))
 			continue
 		}
-		if clientInputFrameId < pR.LastAllConfirmedInputFrameId {
-			Logger.Debug(fmt.Sprintf("Omitting obsolete inputFrameUpsync#2: roomId=%v, playerId=%v, clientInputFrameId=%v, InputsBuffer=%v", pR.Id, playerId, clientInputFrameId, pR.InputsBufferString(false)))
+		if clientInputFrameId < player.LastReceivedInputFrameId {
+			Logger.Debug(fmt.Sprintf("Omitting obsolete inputFrameUpsync#2: roomId=%v, playerId=%v, clientInputFrameId=%v, playerLastReceivedInputFrameId=%v, InputsBuffer=%v", pR.Id, playerId, clientInputFrameId, player.LastReceivedInputFrameId, pR.InputsBufferString(false)))
 			continue
 		}
 		if clientInputFrameId > pR.InputsBuffer.EdFrameId {
@@ -1079,6 +1080,8 @@ func (pR *Room) markConfirmationIfApplicable(inputFrameUpsyncBatch []*pb.InputFr
 		targetInputFrameDownsync.InputList[player.JoinIndex-1] = inputFrameUpsync.Encoded
 		targetInputFrameDownsync.ConfirmedList |= uint64(1 << uint32(player.JoinIndex-1))
 
+		player.LastReceivedInputFrameId = clientInputFrameId
+
 		if clientInputFrameId > pR.LatestPlayerUpsyncedInputFrameId {
 			pR.LatestPlayerUpsyncedInputFrameId = clientInputFrameId
 		}
diff --git a/frontend/assets/scenes/login.fire b/frontend/assets/scenes/login.fire
index 76a6bfa..e3c7ca3 100644
--- a/frontend/assets/scenes/login.fire
+++ b/frontend/assets/scenes/login.fire
@@ -440,7 +440,7 @@
       "array": [
         0,
         0,
-        216.50635094610968,
+        210.60543794365393,
         0,
         0,
         0,
diff --git a/frontend/assets/scripts/Map.js b/frontend/assets/scripts/Map.js
index e26ed8c..d81652b 100644
--- a/frontend/assets/scripts/Map.js
+++ b/frontend/assets/scripts/Map.js
@@ -1082,14 +1082,6 @@ othersForcedDownsyncRenderFrame=${JSON.stringify(othersForcedDownsyncRenderFrame
       }
       const nextRdf = gopkgs.ApplyInputFrameDownsyncDynamicsOnSingleRenderFrameJs(self.recentInputCache, currRdf, collisionSys, collisionSysMap, self.spaceOffsetX, self.spaceOffsetY, self.chConfigsOrderedByJoinIndex);
 
-      if (3 == nextRdf.PlayersArr[0].ActiveSkillId && 3 != currRdf.PlayersArr[0].ActiveSkillId) {
-        console.log(`Started skill 3 at rdf.Id=${nextRdf.Id}`);
-        self.lastSkill3Started = nextRdf.Id;
-      }
-      if (3 != nextRdf.PlayersArr[0].ActiveSkillId && 3 == currRdf.PlayersArr[0].ActiveSkillId) {
-        console.log(`Stopped skill 3 at rdf.Id=${nextRdf.Id}, duration = ${nextRdf.Id-self.lastSkill3Started}`);
-      }
-
       if (true == isChasing) {
         // [WARNING] Move the cursor "self.chaserRenderFrameId" when "true == isChasing", keep in mind that "self.chaserRenderFrameId" is not monotonic!
         self.chaserRenderFrameId = nextRdf.Id;