Decompile lift

docs/tr2/progress.txt

@@ -2653,6 +2653,11 @@ typedef struct __unaligned {
     int32_t pitch;
 } SKIDOO_INFO;
 
+typedef struct __unaligned { // decompiled
+    int32_t start_height;
+    int32_t wait_time;
+} LIFT_INFO;
+
 typedef struct __unaligned {
     struct {
         XYZ_16 min;
@@ -3580,11 +3585,11 @@ typedef enum {
 0x00435650  0x0036  -R      void __cdecl DrawBridgeFloor(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
 0x00435690  0x003B  -R      void __cdecl DrawBridgeCeiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
 0x004356D0  0x002C  -R      void __cdecl DrawBridgeCollision(int16_t item_num, ITEM *lara_item, COLL_INFO *coll);
-0x00435700  0x0035  -R      void __cdecl InitialiseLift(int16_t item_num);
-0x00435740  0x00D4  -R      void __cdecl LiftControl(int16_t item_num);
-0x00435820  0x0179  -R      void __cdecl LiftFloorCeiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *floor, int32_t *ceiling);
-0x004359A0  0x0035  -R      void __cdecl LiftFloor(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
-0x004359E0  0x0035  -R      void __cdecl LiftCeiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
+0x00435700  0x0035  +       void __cdecl Lift_Initialise(int16_t item_num);
+0x00435740  0x00D4  +       void __cdecl Lift_Control(int16_t item_num);
+0x00435820  0x0179  +       void __cdecl Lift_FloorCeiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *floor, int32_t *ceiling);
+0x004359A0  0x0035  +       void __cdecl Lift_Floor(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
+0x004359E0  0x0035  +       void __cdecl Lift_Ceiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
 0x00435A20  0x0016  -R      void __cdecl BridgeFlatFloor(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
 0x00435A40  0x001B  -R      void __cdecl BridgeFlatCeiling(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height);
 0x00435A60  0x003B  -R      int32_t __cdecl GetOffset(ITEM *item, int32_t x, int32_t z);

src/libtrx/include/libtrx/game/math.h

@@ -6,6 +6,16 @@
 
 #pragma pack(push, 1)
 
+typedef struct __PACKING {
+    int32_t x;
+    int32_t z;
+} XZ_32;
+
+typedef struct __PACKING {
+    int16_t x;
+    int16_t z;
+} XZ_16;
+
 typedef struct __PACKING {
     int32_t x;
     int32_t y;

src/tr2/game/objects/general/lift.c

@@ -0,0 +1,166 @@
+#include "game/objects/general/lift.h"
+
+#include "game/items.h"
+#include "game/room.h"
+#include "global/funcs.h"
+#include "global/vars.h"
+
+#define LIFT_WAIT_TIME (3 * FRAMES_PER_SECOND) // = 90
+#define LIFT_SHIFT 16
+#define LIFT_HEIGHT (STEP_L * 5) // = 1280
+#define LIFT_TRAVEL_DIST (STEP_L * 22)
+
+typedef enum {
+    LIFT_STATE_DOOR_CLOSED = 0,
+    LIFT_STATE_DOOR_OPEN = 1,
+} LIFT_STATE;
+
+void __cdecl Lift_Initialise(const int16_t item_num)
+{
+    ITEM *const item = Item_Get(item_num);
+
+    LIFT_INFO *const lift_data =
+        game_malloc(sizeof(LIFT_INFO), GBUF_TEMP_ALLOC);
+    lift_data->start_height = item->pos.y;
+    lift_data->wait_time = 0;
+
+    item->data = lift_data;
+}
+
+void __cdecl Lift_Control(const int16_t item_num)
+{
+    ITEM *const item = Item_Get(item_num);
+    LIFT_INFO *const lift_data = item->data;
+
+    if (Item_IsTriggerActive(item)) {
+        if (item->pos.y
+            < lift_data->start_height + LIFT_TRAVEL_DIST - LIFT_SHIFT) {
+            if (lift_data->wait_time < LIFT_WAIT_TIME) {
+                item->goal_anim_state = LIFT_STATE_DOOR_OPEN;
+                lift_data->wait_time++;
+            } else {
+                item->goal_anim_state = LIFT_STATE_DOOR_CLOSED;
+                item->pos.y += LIFT_SHIFT;
+            }
+        } else {
+            item->goal_anim_state = LIFT_STATE_DOOR_OPEN;
+            lift_data->wait_time = 0;
+        }
+    } else {
+        if (item->pos.y > lift_data->start_height + LIFT_SHIFT) {
+            if (lift_data->wait_time < LIFT_WAIT_TIME) {
+                item->goal_anim_state = LIFT_STATE_DOOR_OPEN;
+                lift_data->wait_time++;
+            } else {
+                item->goal_anim_state = LIFT_STATE_DOOR_CLOSED;
+                item->pos.y -= LIFT_SHIFT;
+            }
+        } else {
+            item->goal_anim_state = LIFT_STATE_DOOR_OPEN;
+            lift_data->wait_time = 0;
+        }
+    }
+
+    Item_Animate(item);
+
+    int16_t room_num = item->room_num;
+    Room_GetSector(item->pos.x, item->pos.y, item->pos.z, &room_num);
+    if (item->room_num != room_num) {
+        Item_NewRoom(item_num, room_num);
+    }
+}
+
+void __cdecl Lift_FloorCeiling(
+    const ITEM *const item, const int32_t x, const int32_t y, const int32_t z,
+    int32_t *const out_floor, int32_t *const out_ceiling)
+{
+    const XZ_32 lift_tile = {
+        .x = item->pos.x >> WALL_SHIFT,
+        .z = item->pos.z >> WALL_SHIFT,
+    };
+
+    const XZ_32 lara_tile = {
+        .x = g_LaraItem->pos.x >> WALL_SHIFT,
+        .z = g_LaraItem->pos.z >> WALL_SHIFT,
+    };
+
+    const XZ_32 test_tile = {
+        .x = x >> WALL_SHIFT,
+        .z = z >> WALL_SHIFT,
+    };
+
+    // clang-format off
+    const bool point_in_shaft =
+        (test_tile.x == lift_tile.x || test_tile.x + 1 == lift_tile.x) &&
+        (test_tile.z == lift_tile.z || test_tile.z - 1 == lift_tile.z);
+
+    const bool lara_in_shaft =
+        (lara_tile.x == lift_tile.x || lara_tile.x + 1 == lift_tile.x) &&
+        (lara_tile.z == lift_tile.z || lara_tile.z - 1 == lift_tile.z);
+    // clang-format on
+
+    const int32_t lift_floor = item->pos.y;
+    const int32_t lift_ceiling = item->pos.y - LIFT_HEIGHT;
+
+    *out_floor = 0x7FFF;
+    *out_ceiling = -0x7FFF;
+
+    if (lara_in_shaft) {
+        if (item->current_anim_state == LIFT_STATE_DOOR_CLOSED
+            && g_LaraItem->pos.y < lift_floor + STEP_L
+            && g_LaraItem->pos.y > lift_ceiling + STEP_L) {
+            if (point_in_shaft) {
+                *out_floor = lift_floor;
+                *out_ceiling = lift_ceiling + STEP_L;
+            } else {
+                *out_floor = NO_HEIGHT;
+                *out_ceiling = 0x7FFF;
+            }
+        } else if (point_in_shaft) {
+            if (g_LaraItem->pos.y < lift_ceiling + STEP_L) {
+                *out_floor = lift_ceiling;
+            } else if (g_LaraItem->pos.y < lift_floor + STEP_L) {
+                *out_floor = lift_floor;
+                *out_ceiling = lift_ceiling + STEP_L;
+            } else {
+                *out_ceiling = lift_floor + STEP_L;
+            }
+        }
+    } else if (point_in_shaft) {
+        if (y <= lift_ceiling) {
+            *out_floor = lift_ceiling;
+        } else if (y >= lift_floor + STEP_L) {
+            *out_ceiling = lift_floor + STEP_L;
+        } else if (item->current_anim_state == LIFT_STATE_DOOR_OPEN) {
+            *out_floor = lift_floor;
+            *out_ceiling = lift_ceiling + STEP_L;
+        } else {
+            *out_floor = NO_HEIGHT;
+            *out_ceiling = 0x7FFF;
+        }
+    }
+}
+
+void __cdecl Lift_Floor(
+    const ITEM *const item, const int32_t x, const int32_t y, const int32_t z,
+    int32_t *const out_height)
+{
+    int32_t floor;
+    int32_t height;
+    Lift_FloorCeiling(item, x, y, z, &floor, &height);
+    if (floor < *out_height) {
+        *out_height = floor;
+    }
+}
+
+void __cdecl Lift_Ceiling(
+    const ITEM *const item, const int32_t x, const int32_t y, const int32_t z,
+    int32_t *const out_height)
+{
+    int32_t floor;
+    int32_t height;
+    Lift_FloorCeiling(item, x, y, z, &floor, &height);
+    if (height > *out_height) {
+        *out_height = height;
+    }
+}

src/tr2/game/objects/general/lift.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "global/types.h"
+
+typedef struct __PACKING {
+    int32_t start_height;
+    int32_t wait_time;
+} LIFT_INFO;
+
+void __cdecl Lift_Initialise(int16_t item_num);
+void __cdecl Lift_Control(int16_t item_num);
+void __cdecl Lift_FloorCeiling(
+    const ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *out_floor,
+    int32_t *out_ceiling);
+void __cdecl Lift_Floor(
+    const ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *out_height);
+void __cdecl Lift_Ceiling(
+    const ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *out_height);

src/tr2/global/funcs.h

@@ -121,11 +121,6 @@
 #define DrawBridgeFloor ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x00435650)
 #define DrawBridgeCeiling ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x00435690)
 #define DrawBridgeCollision ((void __cdecl (*)(int16_t item_num, ITEM *lara_item, COLL_INFO *coll))0x004356D0)
-#define InitialiseLift ((void __cdecl (*)(int16_t item_num))0x00435700)
-#define LiftControl ((void __cdecl (*)(int16_t item_num))0x00435740)
-#define LiftFloorCeiling ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *floor, int32_t *ceiling))0x00435820)
-#define LiftFloor ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x004359A0)
-#define LiftCeiling ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x004359E0)
 #define BridgeFlatFloor ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x00435A20)
 #define BridgeFlatCeiling ((void __cdecl (*)(ITEM *item, int32_t x, int32_t y, int32_t z, int32_t *height))0x00435A40)
 #define GetOffset ((int32_t __cdecl (*)(ITEM *item, int32_t x, int32_t z))0x00435A60)

src/tr2/inject_exec.c

@@ -53,6 +53,7 @@
 #include "game/objects/general/final_level_counter.h"
 #include "game/objects/general/gong_bonger.h"
 #include "game/objects/general/keyhole.h"
+#include "game/objects/general/lift.h"
 #include "game/objects/general/movable_block.h"
 #include "game/objects/general/pickup.h"
 #include "game/objects/general/puzzle_hole.h"
@@ -1016,6 +1017,11 @@ static void M_Objects(const bool enable)
     INJECT(enable, 0x00434800, GongBonger_Control);
     INJECT(enable, 0x004348C0, Zipline_Collision);
     INJECT(enable, 0x00434980, Zipline_Control);
+    INJECT(enable, 0x00435700, Lift_Initialise);
+    INJECT(enable, 0x00435740, Lift_Control);
+    INJECT(enable, 0x00435820, Lift_FloorCeiling);
+    INJECT(enable, 0x004359A0, Lift_Floor);
+    INJECT(enable, 0x004359E0, Lift_Ceiling);
     INJECT(enable, 0x00435D70, Detonator_Control);
     INJECT(enable, 0x00437E70, Pickup_Collision);
     INJECT(enable, 0x004382F0, Switch_Collision);

src/tr2/meson.build

@@ -168,6 +168,7 @@ dll_sources = [
   'game/objects/general/final_level_counter.c',
   'game/objects/general/gong_bonger.c',
   'game/objects/general/keyhole.c',
+  'game/objects/general/lift.c',
   'game/objects/general/movable_block.c',
   'game/objects/general/pickup.c',
   'game/objects/general/puzzle_hole.c',