Implement fix for Mikau healing cutscene audio (#1165)

1 files changed, 55 insertions, 0 deletions

diff --git a/mm/2s2h/Enhancements/Cutscenes/StoryCutscenes/HealingMikauAudio.cpp b/mm/2s2h/Enhancements/Cutscenes/StoryCutscenes/HealingMikauAudio.cpp
new file mode 100644
index 000000000..edf7bfa15
--- /dev/null
+++ b/mm/2s2h/Enhancements/Cutscenes/StoryCutscenes/HealingMikauAudio.cpp
@@ -0,0 +1,55 @@
+#include "public/bridge/consolevariablebridge.h"
+#include "2s2h/GameInteractor/GameInteractor.h"
+#include "2s2h/ShipInit.hpp"
+
+extern "C" {
+#include "variables.h"
+#include "functions.h"
+}
+
+/*
+ * The cutscene for healing Mikau has a CS_CMD_STOP_SEQ command for NA_BGM_ZORA_HALL for frames 0 and 1. On N64, the
+ * BGM sequence is not yet loaded until frame 10, so there is no sequence to stop. The result is that the Great Bay
+ * Coast sequence plays as normal. 2ship short circuits the delayed sequence loading, which means the main BGM sequence
+ * is active by frame 0, which allows the CS_CMD_STOP_SEQ command to kill the BGM.
+ *
+ * Given that:
+ * 1. The CS_CMD_STOP_SEQ call is for NA_BGM_ZORA_HALL, which wouldn't be playing in this scene anyway
+ * 2. The CS_CMD_STOP_SEQ is immediately at the start for frames 0 and 1, while any other uses in the game have larger
+ *    windows and occur later in their respective cutscenes
+ * 3. CS_CMD_STOP_SEQ takes an argument for the specific sequence ID, but kills that type of sequence (main, sub, etc.)
+ * 4. The subsequent cutscene of Link bowing at Mikau's grave fades out the BGM and then fades it back in
+ * 5. This CS_CMD_STOP_SEQ call effectively does nothing in vanilla because of the delayed audio loading
+ * 6. MM3D plays the Great Bay Coast BGM in this cutscene
+ *
+ * It is probably safe to say that this command is not supposed to be there. This ad-hoc enhancement exists to restore
+ * the vanilla behavior.
+ */
+
+static HOOK_ID playGreatBayCoastBgmHookId = 0;
+
+void RegisterHealingMikauAudioFix() {
+    COND_ID_HOOK(OnActorInit, ACTOR_EN_ZOG, true, [](Actor* actor) {
+        // This is the healing Mikau cutscene
+        if (gSaveContext.save.entrance == ENTRANCE(GREAT_BAY_COAST, 9) && !playGreatBayCoastBgmHookId) {
+            // The main BGM sequence is playing (no BGM plays at night)
+            if (AudioSeq_GetActiveSeqId(SEQ_PLAYER_BGM_MAIN) != NA_BGM_DISABLED) {
+                playGreatBayCoastBgmHookId =
+                    GameInteractor::Instance->RegisterGameHookForID<GameInteractor::OnActorUpdate>(
+                        ACTOR_EN_ZOG, [](Actor* actor) {
+                            // If BGM is killed, replay it and kill this update hook
+                            if (AudioSeq_GetActiveSeqId(SEQ_PLAYER_BGM_MAIN) == NA_BGM_DISABLED) {
+                                SEQCMD_PLAY_SEQUENCE(SEQ_PLAYER_BGM_MAIN, 0, NA_BGM_GREAT_BAY_REGION);
+                                if (playGreatBayCoastBgmHookId) {
+                                    GameInteractor::Instance->UnregisterGameHookForID<GameInteractor::OnActorUpdate>(
+                                        playGreatBayCoastBgmHookId);
+                                    playGreatBayCoastBgmHookId = 0;
+                                }
+                            }
+                        });
+            }
+        }
+    });
+}
+
+static RegisterShipInitFunc initFunc(RegisterHealingMikauAudioFix, {});