Completely rewrote level transition synchronization code

Should be snappier and less prone to crashes. I tested as many scenarios
as I could think of and it has been rock solid. But time will tell.

Also created a new debug log system, just so I could understand what the
hell was going on with this code.

build-windows-visual-studio/sm64ex.vcxproj

@@ -4305,6 +4305,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\include\behavior_table.h" />
+    <ClInclude Include="..\src\pc\debuglog.h" />
     <ClInclude Include="..\src\pc\network\network.h" />
     <ClInclude Include="..\src\pc\network\socket\socket.h" />
     <ClInclude Include="..\src\pc\network\socket\socket_linux.h" />

build-windows-visual-studio/sm64ex.vcxproj.filters

@@ -15928,5 +15928,8 @@
     <ClInclude Include="..\include\behavior_table.h">
       <Filter>Header Files\include</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\pc\debuglog.h">
+      <Filter>Source Files\src\pc</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>

network.sh

@@ -12,6 +12,8 @@ if [ ! -f "$FILE" ]; then
 fi
 
 $FILE --server 27015 --configfile sm64config_server.txt  &
+#$FILE --client 127.0.0.1 27015 --configfile sm64config_client.txt  &
+#exit
 
 # debug if cgdb exists
 if ! [ -x "$(command -v cgdb)" ]; then

src/game/area.c

@@ -254,6 +254,7 @@ void load_area(s32 index) {
 }
 
 void unload_area(void) {
+    network_clear_sync_objects();
     if (gCurrentArea != NULL) {
         unload_objects_from_area(0, gCurrentArea->index);
         geo_call_global_function_nodes(&gCurrentArea->unk04->node, GEO_CONTEXT_AREA_UNLOAD);

src/game/ingame_menu.c

@@ -3123,12 +3123,6 @@ s16 render_course_complete_screen(void) {
     gInGameLanguage = eu_get_language();
 #endif
 
-    // if we went into a painting, no more save menu!
-    if (gInsidePainting == TRUE) {
-        gMenuMode = -1;
-        return 0;
-    }
-
     switch (gDialogBoxState) {
         case DIALOG_STATE_OPENING:
             render_course_complete_lvl_info_and_hud_str();

src/game/level_update.c

@@ -46,6 +46,10 @@
 
 #define WARP_NODE_CREDITS_MIN 0xF8
 
+u8 gControlledWarp = 0;
+u8 gReceiveWarp = 0;
+struct WarpDest gReceiveWarpDest = { 0 };
+
 #ifdef VERSION_JP
 const char *credits01[] = { "1GAME DIRECTOR", "SHIGERU MIYAMOTO" };
 const char *credits02[] = { "2ASSISTANT DIRECTORS", "YOSHIAKI KOIZUMI", "TAKASHI TEZUKA" };
@@ -169,11 +173,6 @@ s8 D_8032C9E0 = 0;
 u8 unused3[4];
 u8 unused4[2];
 
-u8 gInsidePainting = false;
-u8 gControlPainting = false;
-u8 gWaitingForRemotePainting = false;
-struct WarpNode gPaintingWarpNode = { 0 };
-
 u16 level_control_timer(s32 timerOp) {
     switch (timerOp) {
         case TIMER_CONTROL_SHOW:
@@ -361,7 +360,17 @@ void set_mario_initial_action(struct MarioState *m, u32 spawnType, u32 actionArg
     set_mario_initial_cap_powerup(m);
 }
 
+#include <stdio.h>
+
 void init_mario_after_warp(void) {
+    printf("===== init mario =====\n");
+    printf("areaIdx = %d\n", sWarpDest.areaIdx);
+    printf("arg = %d\n", sWarpDest.arg);
+    printf("levelNum = %d\n", sWarpDest.levelNum);
+    printf("nodeId = %d\n", sWarpDest.nodeId);
+    printf("type = %d\n", sWarpDest.type);
+    fflush(stdout);
+
     struct ObjectWarpNode *spawnNode = area_get_warp_node(sWarpDest.nodeId);
     u32 marioSpawnType = get_mario_spawn_type(spawnNode->object);
 
@@ -671,35 +680,7 @@ struct WarpNode *get_painting_warp_node(void) {
     return warpNode;
 }
 
-/**
+static void initiate_painting_warp_node(struct WarpNode *pWarpNode, u8 instant) {
- * Check is Mario has entered a painting, and if so, initiate a warp.
- */
-void initiate_painting_warp(void) {
-    if (gCurrentArea->paintingWarpNodes != NULL && gMarioState->floor != NULL) {
-        struct WarpNode *pWarpNode = get_painting_warp_node();
-
-        if (pWarpNode != NULL) {
-            if (gMarioState->action & ACT_FLAG_INTANGIBLE) {
-                play_painting_eject_sound();
-            } else if (pWarpNode->id != 0) {
-                initiate_painting_warp_node(pWarpNode, false);
-                gControlPainting = true;
-                gWaitingForRemotePainting = (gNetworkType != NT_NONE);
-                set_mario_action(gMarioState, ACT_DISAPPEARED, 0);
-                gMarioState->marioObj->header.gfx.node.flags &= ~GRAPH_RENDER_ACTIVE;
-            }
-        }
-    }
-}
-
-void initiate_painting_warp_node(struct WarpNode *pWarpNode, u8 instant) {
-    if (pWarpNode->id == 0) { return; }
-
-    gControlPainting = false;
-    gWaitingForRemotePainting = false;
-    gInsidePainting = true;
-
-    gPaintingWarpNode = *pWarpNode;
     struct WarpNode warpNode = *pWarpNode;
 
     if (!(warpNode.destLevel & 0x80)) {
@@ -718,6 +699,26 @@ void initiate_painting_warp_node(struct WarpNode *pWarpNode, u8 instant) {
     func_sh_8024C89C(1);
 }
 
+/**
+ * Check is Mario has entered a painting, and if so, initiate a warp.
+ */
+void initiate_painting_warp(void) {
+    if (gCurrentArea->paintingWarpNodes != NULL && gMarioState->floor != NULL) {
+        struct WarpNode *pWarpNode = get_painting_warp_node();
+
+        if (pWarpNode != NULL) {
+            if (gMarioState->action & ACT_FLAG_INTANGIBLE) {
+                play_painting_eject_sound();
+            } else if (pWarpNode->id != 0) {
+                initiate_painting_warp_node(pWarpNode, false);
+                set_mario_action(gMarioState, ACT_DISAPPEARED, 0);
+                gMarioState->marioObj->header.gfx.node.flags &= ~GRAPH_RENDER_ACTIVE;
+            }
+        }
+    }
+}
+
+
 /**
  * If there is not already a delayed warp, schedule one. The source node is
  * based on the warp operation and sometimes Mario's used object.
@@ -727,7 +728,6 @@ s16 level_trigger_warp(struct MarioState *m, s32 warpOp) {
     // only allow for local player
     if (m != &gMarioStates[0]) { return 0; }
 
-    gControlPainting = TRUE;
     s32 val04 = TRUE;
 
     if (sDelayedWarpOp == WARP_OP_NONE) {
@@ -996,6 +996,29 @@ void basic_update(UNUSED s16 *arg) {
     }
 }
 
+static void check_for_received_warp(void) {
+    if (!gReceiveWarp) { return; }
+    gReceiveWarp = FALSE;
+    sWarpDest = gReceiveWarpDest;
+
+    if (!gControlledWarp) {
+        // force well behaved state
+        extern s16 gMenuMode;
+        reset_dialog_render_state();
+        level_set_transition(0, 0);
+        sTransitionUpdate = NULL;
+        gMenuMode = -1;
+        gPauseScreenMode = 1;
+        gSaveOptSelectIndex = 0;
+        gMarioStates[0].action = (gMarioStates[0].pos[1] <= gMarioStates[0].waterLevel) ? ACT_WATER_IDLE : ACT_IDLE;
+        gCameraMovementFlags &= ~CAM_MOVE_PAUSE_SCREEN;
+    }
+
+    set_play_mode((sWarpDest.type == WARP_TYPE_CHANGE_LEVEL)
+                  ? PLAY_MODE_CHANGE_LEVEL
+                  : PLAY_MODE_CHANGE_AREA);
+}
+
 int gPressedStart = 0;
 
 s32 play_mode_normal(void) {
@@ -1036,14 +1059,14 @@ s32 play_mode_normal(void) {
                 set_play_mode(PLAY_MODE_CHANGE_LEVEL);
             } else {
                 set_play_mode((gNetworkType != NT_NONE) ? PLAY_MODE_SYNC_LEVEL : PLAY_MODE_CHANGE_LEVEL);
-                network_send_level_warp();
+                network_send_level_warp(FALSE);
             }
         } else if (sTransitionTimer != 0) {
             if (sWarpDest.type == WARP_TYPE_NOT_WARPING || gCurrentArea->index == sWarpDest.areaIdx) {
                 set_play_mode(PLAY_MODE_CHANGE_AREA);
             } else {
                 set_play_mode((gNetworkType != NT_NONE) ? PLAY_MODE_SYNC_LEVEL : PLAY_MODE_CHANGE_AREA);
-                network_send_level_warp();
+                network_send_level_warp(FALSE);
             }
         } else if (pressed_pause()) {
             lower_background_noise(1);
@@ -1053,6 +1076,8 @@ s32 play_mode_normal(void) {
         }
     }
 
+    check_for_received_warp();
+
     return 0;
 }
 
@@ -1073,7 +1098,7 @@ s32 play_mode_paused(void) {
             gSavedCourseNum = COURSE_NONE;
         }
         set_play_mode((gNetworkType != NT_NONE) ? PLAY_MODE_SYNC_LEVEL : PLAY_MODE_CHANGE_LEVEL);
-        network_send_level_warp();
+        network_send_level_warp(FALSE);
     } else if (gPauseScreenMode == 3) {
         // We should only be getting "int 3" to here
         initiate_warp(LEVEL_CASTLE, 1, 0x1F, 0);
@@ -1087,6 +1112,7 @@ s32 play_mode_paused(void) {
 }
 
 s32 play_mode_sync_level(void) {
+    check_for_received_warp();
     return 0;
 }
 
@@ -1123,8 +1149,6 @@ void level_set_transition(s16 length, void (*updateFunction)(s16 *)) {
  * Play the transition and then return to normal play mode.
  */
 s32 play_mode_change_area(void) {
-    network_on_init_level();
-
     //! This maybe was supposed to be sTransitionTimer == -1? sTransitionUpdate
     // is never set to -1.
     if (sTransitionUpdate == (void (*)(s16 *)) - 1) {
@@ -1222,7 +1246,6 @@ s32 update_level(void) {
 
 s32 init_level(void) {
     reset_dialog_render_state();
-    network_on_init_level();
 
     s32 val4 = 0;
 

src/game/level_update.h

@@ -69,10 +69,6 @@ extern struct CreditsEntry *gCurrCreditsEntry;
 
 extern struct MarioState gMarioStates[];
 extern struct MarioState *gMarioState;
-extern u8 gInsidePainting;
-extern u8 gControlPainting;
-extern u8 gWaitingForRemotePainting;
-extern struct WarpNode gPaintingWarpNode;
 
 extern s16 sCurrPlayMode;
 extern u16 D_80339ECA;
@@ -140,7 +136,6 @@ void basic_update(UNUSED s16 *arg);
 
 s32 init_level(void);
 
-void initiate_painting_warp_node(struct WarpNode *pWarpNode, u8 instant);
 void star_select_finish_selection(void);
 
 #endif // LEVEL_UPDATE_H

src/game/mario.c

@@ -2083,8 +2083,6 @@ static void init_single_mario(struct MarioState* m) {
 }
 
 void init_mario(void) {
-    gInsidePainting = false;
-
     for (int i = 0; i < MAX_PLAYERS; i++) {
         gMarioStates[i].playerIndex = i;
         init_single_mario(&gMarioStates[i]);

src/menu/star_select.c

@@ -33,7 +33,7 @@
 static struct Object *sStarSelectorModels[8];
 
 // The act the course is loaded as, affects whether some objects spawn.
-static s8 sLoadedActNum;
+s8 sLoadedActNum;
 
 // Number of obtained stars, excluding the coin star.
 static u8 sObtainedStars;
@@ -54,6 +54,8 @@ s8 sSelectableStarIndex = 0;
 // Act Selector menu timer that keeps counting until you choose an act.
 static s32 sActSelectorMenuTimer = 0;
 
+extern u8 gControlledWarp;
+
 /**
  * Act Selector Star Type Loop Action
  * Defines a select type for a star in the act selector.
@@ -156,7 +158,10 @@ void bhv_act_selector_init(void) {
     }
 
     render_100_coin_star(stars);
-    gInsidePainting = TRUE;
+
+    if (gControlledWarp) {
+        network_send_inside_painting(TRUE, FALSE);
+    }
 }
 
 /**
@@ -175,7 +180,11 @@ void bhv_act_selector_loop(void) {
         // Sometimes, stars are not selectable even if they appear on the screen.
         // This code filters selectable and non-selectable stars.
         sSelectedActIndex = 0;
-        if (gControlPainting) { handle_menu_scrolling(MENU_SCROLL_HORIZONTAL, &sSelectableStarIndex, 0, sObtainedStars); }
+        if (gControlledWarp) {
+            s8 oldIndex = sSelectableStarIndex;
+            handle_menu_scrolling(MENU_SCROLL_HORIZONTAL, &sSelectableStarIndex, 0, sObtainedStars);
+            if (oldIndex != sSelectableStarIndex) { network_send_inside_painting(FALSE, FALSE); }
+        }
         starIndexCounter = sSelectableStarIndex;
         for (i = 0; i < sVisibleStars; i++) {
             // Can the star be selected (is it either already completed or the first non-completed mission)
@@ -189,7 +198,11 @@ void bhv_act_selector_loop(void) {
         }
     } else {
         // If all stars are collected then they are all selectable.
-        if (gControlPainting) { handle_menu_scrolling(MENU_SCROLL_HORIZONTAL, &sSelectableStarIndex, 0, sVisibleStars - 1); }
+        if (gControlledWarp) {
+            s8 oldIndex = sSelectableStarIndex;
+            handle_menu_scrolling(MENU_SCROLL_HORIZONTAL, &sSelectableStarIndex, 0, sVisibleStars - 1);
+            if (oldIndex != sSelectableStarIndex) { network_send_inside_painting(FALSE, FALSE); }
+        }
         sSelectedActIndex = sSelectableStarIndex;
     }
 
@@ -289,7 +302,7 @@ void print_act_selector_strings(void) {
     create_dl_ortho_matrix();
 
     // display disclaimer that the other player has to select
-    if (!gControlPainting || gWaitingForRemotePainting) {
+    if (!gControlledWarp) {
         gSPDisplayList(gDisplayListHead++, dl_ia_text_begin);
         u8 a = ((gGlobalTimer % 24) >= 12) ? 160 : 130;
         gDPSetEnvColor(gDisplayListHead++, 0, 0, 0, a);
@@ -426,8 +439,7 @@ s32 lvl_init_act_selector_values_and_stars(UNUSED s32 arg, UNUSED s32 unused) {
  * Also updates objects and returns act number selected after is chosen.
  */
 s32 lvl_update_obj_and_load_act_button_actions(UNUSED s32 arg, UNUSED s32 unused) {
-    u8 allowSelection = (gControlPainting && !gWaitingForRemotePainting);
+    if (gControlledWarp && sActSelectorMenuTimer >= 11) {
-    if (sActSelectorMenuTimer >= 11 && allowSelection) {
         // If any of these buttons are pressed, play sound and go to course act
 #ifndef VERSION_EU
         if ((gPlayer3Controller->buttonPressed & A_BUTTON)
@@ -458,8 +470,5 @@ void star_select_finish_selection(void) {
     }
     gDialogCourseActNum = sSelectedActIndex + 1;
 
-    gInsidePainting = FALSE;
+    if (gControlledWarp) { network_send_inside_painting(FALSE, TRUE); }
-    if (gControlPainting) {
-        network_send_inside_painting(TRUE);
-    }
 }

src/pc/debuglog.h

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <time.h>
+#include "pc/network/network.h"
+
+#if defined(DEBUG) && !defined(DISABLE_MODULE_LOG)
+    static void debuglog_print_timestamp(void) {
+        time_t ltime = time(NULL);
+        char* str = asctime(localtime(&ltime));
+        printf("%.*s", (int)strlen(str) - 1, str);
+    }
+
+    static void debuglog_print_network_type(void) {
+        printf(" [%s] ", NETWORKTYPESTR);
+    }
+
+    static void debuglog_print_short_filename(char* filename) {
+        char* last = strrchr(filename, '/');
+        if (last != NULL) {
+            printf("%s: ", last + 1);
+        } else {
+            printf("???: ");
+        }
+    }
+
+    static void debuglog_print_log(char* filename) {
+        debuglog_print_timestamp();
+        debuglog_print_network_type();
+        debuglog_print_short_filename(filename);
+    }
+
+    #define LOG_INFO(...) ( debuglog_print_log(__FILE__), printf(__VA_ARGS__), printf("\n") )
+#else
+    #define LOG_INFO(...)
+#endif

src/pc/network/network.c

@@ -6,7 +6,6 @@
 #include "pc/configfile.h"
 
 // Mario 64 specific externs
-extern u8 gInsidePainting;
 extern s16 sCurrPlayMode;
 
 enum NetworkType gNetworkType = NT_NONE;
@@ -105,9 +104,7 @@ void network_update(void) {
     }
 
     // figure out which update loop to run
-    if (gInsidePainting && sCurrPlayMode == PLAY_MODE_CHANGE_LEVEL) {
+    if (sCurrPlayMode == PLAY_MODE_NORMAL || sCurrPlayMode == PLAY_MODE_PAUSED) {
-        network_update_inside_painting();
-    } else if (sCurrPlayMode == PLAY_MODE_NORMAL || sCurrPlayMode == PLAY_MODE_PAUSED) {
         network_update_player();
         network_update_objects();
     }

src/pc/network/network.h

@@ -131,12 +131,11 @@ void network_send_spawn_star(struct Object* o, u8 starType, f32 x, f32 y, f32 z,
 void network_receive_spawn_star(struct Packet* p);
 
 // packet_level_warp.c
-void network_send_level_warp(void);
+void network_send_level_warp(u8 done);
 void network_receive_level_warp(struct Packet* p);
 
 // packet_inside_painting.c
-void network_update_inside_painting(void);
+void network_send_inside_painting(u8 startOfEvent, u8 endOfEvent);
-void network_send_inside_painting(bool reliable);
 void network_receive_inside_painting(struct Packet* p);
 
 // packet_collect_star.c

src/pc/network/packets/packet_inside_painting.c

@@ -2,81 +2,83 @@
 #include "../network.h"
 #include "src/game/level_update.h"
 #include "src/game/area.h"
+#define DISABLE_MODULE_LOG
+#include "pc/debuglog.h"
+
+extern u8 gControlledWarp;
 
-extern struct WarpNode gPaintingWarpNode;
 extern u8 sSelectableStarIndex;
 extern u8 sSelectedActIndex;
+extern s8 sLoadedActNum;
 
-struct PacketDataInsidePainting {
+#pragma pack(1)
-    u8 insidePainting;
+struct PacketInsidePaintingData {
-    u8 controlPainting;
+    u8 seqId;
+    u8 eventId;
     u8 starIndex;
     u8 actIndex;
+    u8 loadedActNum;
 };
 
-static clock_t lastSentTime = 0;
+static u8 eventId = 0;
-static float minUpdateRate = 5.0f;
+static u8 remoteFinishedEventId = (u8)-1;
-static struct PacketDataInsidePainting lastSentData = { 0 };
 
-static void populate_packet_data(struct PacketDataInsidePainting* data) {
+static u8 seqId = 0;
-    data->insidePainting = gInsidePainting;
+static u8 remoteLastSeqId = (u8)-1;
-    data->controlPainting = gControlPainting;
+
+static void populate_packet_data(struct PacketInsidePaintingData* data) {
+    data->seqId = seqId;
+    data->eventId = eventId;
     data->starIndex = sSelectableStarIndex;
     data->actIndex = sSelectedActIndex;
+    data->loadedActNum = sLoadedActNum;
 }
 
-void network_send_inside_painting(bool reliable) {
+void network_send_inside_painting(u8 startOfEvent, u8 endOfEvent) {
-    struct PacketDataInsidePainting data = { 0 };
+    if (startOfEvent) { eventId++; }
+    struct PacketInsidePaintingData data = { 0 };
     populate_packet_data(&data);
 
     struct Packet p;
-    packet_init(&p, PACKET_INSIDE_PAINTING, reliable);
+    packet_init(&p, PACKET_INSIDE_PAINTING, true);
-    packet_write(&p, &data, sizeof(struct PacketDataInsidePainting));
+    packet_write(&p, &data, sizeof(struct PacketInsidePaintingData));
     network_send(&p);
-
+    seqId++;
-    lastSentData = data;
-    lastSentTime = clock();
 }
 
 void network_receive_inside_painting(struct Packet* p) {
-    struct PacketDataInsidePainting remote = { 0 };
+    struct PacketInsidePaintingData local = { 0 };
-    packet_read(p, &remote, sizeof(struct PacketDataInsidePainting));
+    populate_packet_data(&local);
 
-    if (gNetworkType == NT_CLIENT && gControlPainting && remote.controlPainting) {
+    struct PacketInsidePaintingData remote = { 0 };
-        // we both think we should control the painting, host wins the tie
+    packet_read(p, &remote, sizeof(struct PacketInsidePaintingData));
-        gControlPainting = false;
+
+    // de-dup
+    if (remote.seqId == remoteLastSeqId) {
+        LOG_INFO("we've seen this packet, escape!");
+        return;
+    }
+    remoteLastSeqId = remote.seqId;
+    if (remote.eventId == remoteFinishedEventId || (remote.eventId == remoteFinishedEventId - 1)) {
+        LOG_INFO("we've finished this event, escape!");
+        return;
     }
 
-    if (!gControlPainting && remote.controlPainting) {
+    // two-player hack: gControlledWarp is a bool instead of an index
-        // update star/act index to show the one in control's selection
+    if (gControlledWarp) {
-        sSelectableStarIndex = remote.starIndex;
+        LOG_INFO("this should never happen, received inside_painting when gControlledWarp");
-        sSelectedActIndex = remote.actIndex;
+        return;
     }
 
-    if (gControlPainting && !remote.controlPainting) {
+    LOG_INFO("received update");
-        // remote is well behaved now, we can control the painting
+    eventId = remote.eventId;
-        gWaitingForRemotePainting = false;
+    sSelectableStarIndex = remote.starIndex;
-    }
+    sSelectedActIndex = remote.actIndex;
+    sLoadedActNum = remote.loadedActNum;
 
-    if (gControlPainting && !remote.controlPainting && !gInsidePainting && remote.insidePainting) {
+    if (sLoadedActNum != 0) {
-        // we're in control and no longer in the painting, let remote know
+        LOG_INFO("finished with painting");
-        network_send_inside_painting(false);
+        remoteFinishedEventId = remote.eventId;
-    }
-
-    if (!gControlPainting && remote.controlPainting && !remote.insidePainting) {
-        // remote is in control and in game, we should be too
-        star_select_finish_selection();
     }
 }
 
-void network_update_inside_painting(void) {
-    struct PacketDataInsidePainting data = { 0 };
-    populate_packet_data(&data);
-    int compareData = memcmp(&data, &lastSentData, sizeof(struct PacketDataInsidePainting));
-
-    float timeSinceSend = (clock() - lastSentTime) / CLOCKS_PER_SEC;
-
-    if (compareData != 0 || timeSinceSend > minUpdateRate) {
-        network_send_inside_painting(timeSinceSend > 5);
-    }
-}

src/pc/network/packets/packet_level_warp.c

@@ -1,73 +1,114 @@
 #include <stdio.h>
-#include "../network.h"
-#include "src/game/level_update.h"
-#include "src/game/area.h"
-#include "src/game/ingame_menu.h"
 #include "sm64.h"
+#include "../network.h"
+#include "game/level_update.h"
+#include "game/area.h"
+#include "game/ingame_menu.h"
+#define DISABLE_MODULE_LOG
+#include "pc/debuglog.h"
 
-int matchCount = 0;
+static u8 eventId = 0;
+static u8 remoteFinishedEventId = (u8)-1;
 
-extern s16 gMenuMode;
+static u8 seqId = 0;
+static u8 remoteLastSeqId = (u8)-1;
 
-void network_send_level_warp(void) {
+extern u8 gControlledWarp; // two-player hack
-    struct Packet p;
+extern u8 gReceiveWarp;
-    packet_init(&p, PACKET_LEVEL_WARP, true);
+extern struct WarpDest gReceiveWarpDest;
-    packet_write(&p, &sCurrPlayMode, sizeof(s16));
-    packet_write(&p, &sWarpDest, sizeof(struct WarpDest));
 
-    network_send(&p);
+struct WarpDest savedWarpNode = { 0 };
+
+#pragma pack(1)
+struct PacketLevelWarpData {
+    u8 seqId;
+    u8 eventId;
+    u8 done;
+    u8 controlledWarp;
+    struct WarpDest warpDest;
+};
+
+static void populate_packet_data(struct PacketLevelWarpData* data, bool done) {
+    data->seqId = seqId;
+    data->eventId = eventId;
+    data->done = done;
+    data->controlledWarp = gControlledWarp;
+    data->warpDest = savedWarpNode;
 }
 
-static void force_well_behaved_state(void) {
+void network_send_level_warp(u8 done) {
-    reset_dialog_render_state();
+    if (!done) {
-    level_set_transition(0, 0);
+        savedWarpNode = sWarpDest;
-    gMenuMode = -1;
+        gControlledWarp = true;
-    gPauseScreenMode = 1;
+        eventId++;
-    gSaveOptSelectIndex = 0;
+        LOG_INFO("new event [%d]!", eventId);
-    gMarioStates[0].action = (gMarioStates[0].pos[1] <= (gMarioStates[0].waterLevel - 100)) ? ACT_WATER_IDLE : ACT_IDLE;
+    }
-    gCameraMovementFlags &= ~CAM_MOVE_PAUSE_SCREEN;
+
+    struct PacketLevelWarpData data = { 0 };
+    populate_packet_data(&data, done);
+
+    struct Packet p;
+    packet_init(&p, PACKET_LEVEL_WARP, true);
+    packet_write(&p, &data, sizeof(struct PacketLevelWarpData));
+    network_send(&p);
+
+    seqId++;
+}
+
+static void do_warp(void) {
+    gReceiveWarpDest = savedWarpNode;
+    gReceiveWarp = TRUE;
 }
 
 void network_receive_level_warp(struct Packet* p) {
-    s16 remotePlayMode;
+    struct PacketLevelWarpData remote = { 0 };
-    struct WarpDest remoteWarpDest;
+    packet_read(p, &remote, sizeof(struct PacketLevelWarpData));
 
-    packet_read(p, &remotePlayMode, sizeof(s16));
+    // de-dup
-    packet_read(p, &remoteWarpDest, sizeof(struct WarpDest));
+    if (remote.seqId == remoteLastSeqId) {
-
+        LOG_INFO("we've seen this packet, escape!");
-    bool matchingDest = memcmp(&remoteWarpDest, &sWarpDest, sizeof(struct WarpDest)) == 0;
+        return;
-
+    }
-    if (remotePlayMode == PLAY_MODE_SYNC_LEVEL && (sCurrPlayMode == PLAY_MODE_NORMAL || sCurrPlayMode == PLAY_MODE_PAUSED)) {
+    remoteLastSeqId = remote.seqId;
-        if (remoteWarpDest.type == WARP_TYPE_NOT_WARPING) { return; }
+    LOG_INFO("rx event [%d] last [%d]!", remote.eventId, remoteFinishedEventId);
-        sCurrPlayMode = PLAY_MODE_SYNC_LEVEL;
+    if (remote.eventId == remoteFinishedEventId || (remote.eventId == remoteFinishedEventId - 1)) {
-        sWarpDest = remoteWarpDest;
+        LOG_INFO("we've finished this event, escape!");
-        force_well_behaved_state();
-        network_send_level_warp();
         return;
     }
 
-    if (remotePlayMode == PLAY_MODE_SYNC_LEVEL && sCurrPlayMode == PLAY_MODE_SYNC_LEVEL) {
+    if (gNetworkType == NT_SERVER) {
-        if (matchingDest) {
+        if (sCurrPlayMode != PLAY_MODE_SYNC_LEVEL) {
-            switch (sWarpDest.type) {
+            // client initiated warp
-                case WARP_TYPE_CHANGE_AREA: sCurrPlayMode = PLAY_MODE_CHANGE_AREA; break;
+            LOG_INFO("client initiated warp!");
-                case WARP_TYPE_CHANGE_LEVEL: sCurrPlayMode = PLAY_MODE_CHANGE_LEVEL; break;
+            gControlledWarp = FALSE;
-            }
+            savedWarpNode = remote.warpDest;
+            eventId = remote.eventId;
+            remoteFinishedEventId = remote.eventId;
+            LOG_INFO("finished event [%d]!", remote.eventId);
+            do_warp();
+            network_send_level_warp(TRUE);
+            return;
+        } else if (remote.done) {
+            // client done with warp
+            LOG_INFO("client is done with warp, lets-a-go!");
+            remoteFinishedEventId = remote.eventId;
+            do_warp();
+            return;
         } else {
-            if (gNetworkType == NT_CLIENT) {
+            LOG_INFO("client initiated warp, but server is already warping!");
-                if (remoteWarpDest.type == WARP_TYPE_NOT_WARPING) { return; }
+            return;
-                // two-player hack: would need to use player index as priority
-                sWarpDest = remoteWarpDest;
-            }
         }
-        network_send_level_warp();
-        return;
     }
 
-    if ((remotePlayMode == PLAY_MODE_CHANGE_LEVEL || remotePlayMode == PLAY_MODE_CHANGE_AREA) && sCurrPlayMode == PLAY_MODE_SYNC_LEVEL) {
+    assert(gNetworkType == NT_CLIENT);
-        if (remoteWarpDest.type == WARP_TYPE_NOT_WARPING) { return; }
+
-        switch (sWarpDest.type) {
+    // server initiated warp
-            case WARP_TYPE_CHANGE_AREA: sCurrPlayMode = PLAY_MODE_CHANGE_AREA; break;
+    LOG_INFO("server initiated warp!");
-            case WARP_TYPE_CHANGE_LEVEL: sCurrPlayMode = PLAY_MODE_CHANGE_LEVEL; break;
+    gControlledWarp = !remote.controlledWarp; // two-player hack
-        }
+    savedWarpNode = remote.warpDest;
-    }
+    eventId = remote.eventId;
+    remoteFinishedEventId = remote.eventId;
+    LOG_INFO("finished event [%d]!", remote.eventId);
+    do_warp();
+    network_send_level_warp(TRUE);
 }

src/pc/network/packets/packet_object.c

@@ -83,6 +83,7 @@ bool network_sync_object_initialized(struct Object* o) {
 }
 
 void network_clear_sync_objects(void) {
+    network_on_init_level();
     for (u16 i = 0; i < MAX_SYNC_OBJECTS; i++) {
         network_forget_sync_object(&gSyncObjects[i]);
     }