Decomp, update `z_en_holl.c` (#6890)

4 files changed, 43 insertions, 6 deletions

diff --git a/soh/include/functions.h b/soh/include/functions.h
index d371bdd19..611b55be3 100644
--- a/soh/include/functions.h
+++ b/soh/include/functions.h
@@ -1238,10 +1238,10 @@ void Room_DrawBackground2D(Gfx** gfxP, void* tex, void* tlut, u16 width, u16 hei
                            u16 tlutCount, f32 offsetX, f32 offsetY);
 void func_80096FD4(PlayState* play, Room* room);
 u32 func_80096FE8(PlayState* play, RoomContext* roomCtx);
-s32 func_8009728C(PlayState* play, RoomContext* roomCtx, s32 roomNum);
+s32 Room_RequestNewRoom(PlayState* play, RoomContext* roomCtx, s32 roomNum);
 s32 func_800973FC(PlayState* play, RoomContext* roomCtx);
 void Room_Draw(PlayState* play, Room* room, u32 flags);
-void func_80097534(PlayState* play, RoomContext* roomCtx);
+void Room_FinishRoomChange(PlayState* play, RoomContext* roomCtx);
 void Sample_Destroy(GameState* thisx);
 void Sample_Init(GameState* thisx);
 void Inventory_ChangeEquipment(s16 equipment, u16 value);
diff --git a/soh/include/z64.h b/soh/include/z64.h
index 3c4daf91c..9e46d3c28 100644
--- a/soh/include/z64.h
+++ b/soh/include/z64.h
@@ -1084,7 +1084,7 @@ typedef struct {
     /* 0x00 */ Room  curRoom;
     /* 0x14 */ Room  prevRoom;
     /* 0x28 */ void* bufPtrs[2];
-    /* 0x30 */ u8    unk_30;
+    /* 0x30 */ u8    activeBufPage;
     /* 0x31 */ s8    status;
     /* 0x34 */ void* unk_34;
     /* 0x38 */ DmaRequest dmaRequest;
@@ -1477,7 +1477,7 @@ typedef struct PlayState {
     /* 0x11E14 */ u8 skyboxId;
     /* 0x11E15 */ s8 transitionTrigger; // "fade_direction"
     /* 0x11E16 */ s16 unk_11E16;
-    /* 0x11E18 */ s16 unk_11E18;
+    /* 0x11E18 */ s16 bgCoverAlpha;
     /* 0x11E1A */ s16 nextEntranceIndex;
     /* 0x11E1C */ char unk_11E1C[0x40];
     /* 0x11E5C */ s8 shootingGalleryStatus;
diff --git a/soh/include/z64actor.h b/soh/include/z64actor.h
index 77172bda4..1fbc688b2 100644
--- a/soh/include/z64actor.h
+++ b/soh/include/z64actor.h
@@ -472,4 +472,41 @@ typedef struct {
     /* 0x24 */ char unk_24[0x4];
 } NpcInteractInfo; // size = 0x28
 
+// Converts a number of bits to a bitmask, helper for params macros
+// e.g. 3 becomes 0b111 (7)
+#define NBITS_TO_MASK(n) \
+    ((1 << (n)) - 1)
+
+// Extracts the `n`-bit value at position `s` in `p`, shifts then masks
+// Unsigned variant, no possibility of sign extension
+#define PARAMS_GET_U(p, s, n) \
+    (((p) >> (s)) & NBITS_TO_MASK(n))
+
+// Extracts the `n`-bit value at position `s` in `p`, masks then shifts
+// Signed variant, possibility of sign extension
+#define PARAMS_GET_S(p, s, n) \
+    (((p) & (NBITS_TO_MASK(n) << (s))) >> (s))
+
+// Extracts all bits past position `s` in `p`
+#define PARAMS_GET_NOMASK(p, s) \
+    ((p) >> (s))
+
+// Extracts the `n`-bit value at position `s` in `p` without shifting it from its current position
+#define PARAMS_GET_NOSHIFT(p, s, n) \
+    ((p) & (NBITS_TO_MASK(n) << (s)))
+
+// Moves the `n`-bit value `p` to bit position `s` for building actor parameters by OR-ing these together
+#define PARAMS_PACK(p, s, n) \
+    (((p) & NBITS_TO_MASK(n)) << (s))
+
+// Moves the value `p` to bit position `s` for building actor parameters by OR-ing these together.
+#define PARAMS_PACK_NOMASK(p, s) \
+    ((p) << (s))
+
+// Generates a bitmask for bit position `s` of length `n`
+#define PARAMS_MAKE_MASK(s, n) PARAMS_GET_NOSHIFT(~0, s, n)
+
+#define TRANSITION_ACTOR_PARAMS_INDEX_SHIFT 10
+#define GET_TRANSITION_ACTOR_INDEX(actor) PARAMS_GET_NOMASK((u16)(actor)->params, 10)
+
 #endif
diff --git a/soh/include/z64save.h b/soh/include/z64save.h
index 35f30c263..baf192aad 100644
--- a/soh/include/z64save.h
+++ b/soh/include/z64save.h
@@ -292,7 +292,7 @@ typedef struct {
     /* 0x1354 */ s32 fileNum; // "file_no"
     /* 0x1358 */ char unk_1358[0x0004];
     /* 0x135C */ s32 gameMode;
-    /* 0x1360 */ s32 sceneSetupIndex; // "counter" // Upstream TODO: sceneLayer
+    /* 0x1360 */ s32 sceneLayer; // "counter"
     /* 0x1364 */ s32 respawnFlag; // "restart_flag"
     /* 0x1368 */ RespawnData respawn[RESPAWN_MODE_MAX]; // "restart_data"
     /* 0x13BC */ f32 entranceSpeed;
@@ -423,7 +423,7 @@ typedef enum {
     /* 4 */ SCENE_LAYER_CUTSCENE_FIRST
 } SceneLayer;
 
-#define IS_CUTSCENE_LAYER (gSaveContext.sceneSetupIndex >= SCENE_LAYER_CUTSCENE_FIRST)
+#define IS_CUTSCENE_LAYER (gSaveContext.sceneLayer >= SCENE_LAYER_CUTSCENE_FIRST)
 
 typedef enum {
     /* 0 */ LINK_AGE_ADULT,