Refactor shop code to use generic Item (#536)

* Turned SpriteObject into a member of JokerObject and CardObject and expiremented with casting

* Extracted shop code to use generic `SpriteObject`

* Extracted shop joker generation to a function

* Renamed object -> item

* Added setters and getters for `SpriteObject` members and updated all accesses to use them with casting (AI used for tedious work and reviewed - model Raptor mini)

* Added sprite_object_set_vx() because sprite_object_set_vy() exists and reordered the function order to have x,y parameters first, then targets

* Added Item object to act as a purchasable interface for the shop - AI used (model Raptor mini)

* Added -fms-extensions and switched to anonymous inheritance

* Fixed anonymous inheritance for joker and added direct access for that too

* fix build error from previous commit + clang-format

* Fixed build errors + clang-format for real this time (I hope...)

* clang-format one last time, I don't understand it anymore

* clang-format is annoying

* Added uses of CHECK_NULL_ARG macros

* Merged item_defs.h into item.h and fixed build error from previous commit

* clang-format...?

* Changed sprite_object_new() into sprite_object_init() and made it accept a parameter instead of returning one to make it less awkward

* Updated sprite_object_init() documentation

* Updated sprite_object_destroy documentation

* More clang-format

* Renamed add_to_inventory to acquire and updated documentation

* Added function documentations

* Update documentation + swap order of consumable and playing card types

* Added documentation for new files (+ small addition to button.h)

* clang-format

* Used typedef

* A bit more documentation

* Changed sho pcode to use generic Item instead of SpriteObject

* clang-format + fixed NULL-check error

* Revert weird clang-format...?

* clang-format for real

* Fixed errors from rebase on log_function_name

* Fixed build errors from rebase on main

* Added some more documentation about first member struct inheritance

* typo fix

* typo fix for real

* Removed SpriteObject field getters/setters (AI used - model Raptor mini)

* Renamed item_acquire -> item_on_acquired

* Added item_can_acquire()

* clang-format

* Fixed some sprite issues but not all...

* Fixed some more issues

* Cleanup JokerObject some more JokerObjects in the shop

* Added `item_destroy()`

* Added item_set_available_to_shop, CHECK_ITEM_TYPE macros + small documentation updates

* Another small JokerObject->Item replacement

* Removed item_set_available_to_shop and replaced with item_roll_new() and item_dispose(), also changed "available_to_shop" semantics to "rollable"

* Re-applied changes from game.c to round.c after rebase on main

* Added partial implementations of item functions for playing cards

* Line endings fix...

* Macro renames, function documentations

* Updated documentations

* Apply fixes from Copilot review

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Fix card_object_get_buy_price type checking

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Avoid double pointer cast on dispose

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Apply suggestions from @ricfehr3's code review

Co-authored-by: Rickey <ric@rf3.xyz>

* Remove redundant comments

* Moved error checking before joker_get_random_rarity

Co-authored-by: Rickey <ric@rf3.xyz>

* Fixed build error from rebase

* clang-format

* Added doxygen documentation for Item explaining inheritance

* Removed unnecessary comment

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Rickey <ric@rf3.xyz>

Makefile

@@ -46,6 +46,7 @@ GIT_C_FLAGS := -DGIT_HASH=\"$(GIT_HASH)\" -DGIT_DIRTY=\"$(GIT_DIRTY)\"
 CFLAGS	:= -g -O3 -Wall -Werror -std=gnu23 \
         -mcpu=arm7tdmi -mtune=arm7tdmi \
         -ffast-math -fomit-frame-pointer -funroll-loops \
+		-fms-extensions \
         $(ARCH)
 
 CFLAGS  += $(GIT_C_FLAGS)

include/button.h

@@ -2,6 +2,7 @@
  * @file button.h
  *
  * @brief A button structure containing the common button functionalities
+ * Including highlight and pressing functionalities.
  */
 
 #ifndef BUTTON_H

include/card.h

@@ -2,7 +2,7 @@
 #define CARD_H
 
 #include "deck_types.h"
-#include "sprite.h"
+#include "item.h"
 
 #include <maxmod.h>
 #include <tonc.h>
@@ -54,8 +54,8 @@ typedef struct Card
 
 typedef struct CardObject
 {
+    Item; // First member struct inheritance
     Card* card;
-    SpriteObject* sprite_object;
     bool selected;
 } CardObject;
 
@@ -83,4 +83,7 @@ void card_object_set_selected(CardObject* card_object, bool selected);
 bool card_object_is_selected(CardObject* card_object);
 Sprite* card_object_get_sprite(CardObject* card_object);
 
+int card_object_get_buy_price(Item* card_object);
+void card_object_dispose(Item** card_object);
+
 #endif // CARD_H

include/def_balatro_mempool.h

@@ -4,7 +4,6 @@
 #include "sprite.h"
 
 POOL_ENTRY(Sprite, MAX_SPRITES);
-POOL_ENTRY(SpriteObject, MAX_SPRITE_OBJECTS);
 POOL_ENTRY(Joker, MAX_ACTIVE_JOKERS);
 POOL_ENTRY(JokerObject, MAX_ACTIVE_JOKERS);
 POOL_ENTRY(Card, MAX_CARDS);

include/game.h

@@ -4,12 +4,13 @@
 #include "game/common_ui.h"
 #include "game_variables.h"
 #include "graphic_utils.h"
+#include "item.h"
 
 #include <tonc.h>
 
 #define MAX_DECK_SIZE        52
 #define MAX_JOKERS_HELD_SIZE 5 // This doesn't account for negatives right now.
-#define MAX_SHOP_JOKERS      2 // TODO: Make this dynamic and allow for other items besides jokers
+#define MAX_SHOP_ITEMS       2 // TODO: Make this dynamic
 #define MAX_SELECTION_SIZE   5
 #define FRAMES(x)            (((x) + (g_game_vars.game_speed) - 1) / (g_game_vars.game_speed))
 
@@ -69,6 +70,7 @@ void game_change_state(enum GameState new_game_state);
 enum GameState game_get_state(void);
 
 bool is_joker_owned(int joker_id);
+bool joker_object_can_acquire(Item* item);
 bool card_is_face(Card* card);
 void add_joker(JokerObject* joker_object);
 void remove_owned_joker(int owned_joker_idx);

include/game/shop.h

@@ -23,14 +23,6 @@ void game_shop_reset(void);
  */
 JokerObject* game_shop_get_description_card(void);
 
-/**
- * @brief Set whether a Joker can appear in the shop.
- *
- * @param avail - true to make it available to the shop to appear in
- *                false to make it unavailable.
- */
-void game_shop_set_joker_avail(int joker_id, bool avail);
-
 /**
  * @brief Change to the shop background
  */

include/item.h

@@ -0,0 +1,173 @@
+/**
+ * @file item.h
+ *
+ * @brief The core structure for items in the shop and inventory.
+ * Provides a common API for the shop and inventory to handle all types of items.
+ * Uses struct inheritance so all inherited items can implement an is-a relationship with Item.
+ * This means that pointers to structs that inherit Item using first member struct inheritance
+ * can and should be cast to Item* so code that expects an Item* can use them.
+ */
+
+#ifndef ITEM_H
+#define ITEM_H
+
+#include "mgba_logger.h"
+#include "sprite.h"
+
+// TODO: Merge these with GBAL_RETURN_IF_NULL macros?
+/**
+ * @brief Checks if @p item is of type @p expected_type - logs error message and returns otherwise
+ *
+ *  This version is for a function that returns a value, while
+ *  @ref ITEM_RETURN_IF_UNEXPECTED_TYPE_VOID is for a void function.
+ */
+#define ITEM_RETURN_IF_UNEXPECTED_TYPE_RET(item, expected_type, ret_val)         \
+    do                                                                           \
+    {                                                                            \
+        if ((item)->type != expected_type)                                       \
+        {                                                                        \
+            MGBA_FUNC_ERROR("Unexpected %s->type != %s", #item, #expected_type); \
+            return (ret_val);                                                    \
+        }                                                                        \
+    } while (0)
+
+/**
+ * @brief Checks if @p item is of type @p expected_type - logs error message and returns otherwise
+ *
+ * This version is for a void function, while @ref ITEM_RETURN_IF_UNEXPECTED_TYPE_RET is for one
+ * with a return value.
+ */
+#define ITEM_RETURN_IF_UNEXPECTED_TYPE_VOID(item, expected_type)                 \
+    do                                                                           \
+    {                                                                            \
+        if ((item)->type != expected_type)                                       \
+        {                                                                        \
+            MGBA_FUNC_ERROR("Unexpected %s->type != %s", #item, #expected_type); \
+            return;                                                              \
+        }                                                                        \
+    } while (0)
+
+enum ItemType
+{
+    ITEM_TYPE_JOKER,
+    ITEM_TYPE_PLAYING_CARD,
+
+    // Future planned item types
+    // ITEM_TYPE_CONSUMABLE, // Expand to PLANET, TAROT, and SPECTRAL?
+    // ITEM_TYPE_VOUCHER,
+    // ITEM_TYPE_PACK
+
+    ITEM_NUM_TYPES
+};
+
+/**
+ * @brief A generic interface for all items that can appear in the shop or be in the inventory.
+ * This uses first member struct inheritance - other structs are meant to inherit it by
+ * making their first member field Item.
+ * Then casts from inheriting structs to Item* are allowed and intentional and this allows for
+ * generic code that uses polymorphism.
+ * The -fms-extensions compile flag allows for anonymous members making it behave fully
+ * as inheritance. It makes all member fields be fully inherited so any struct
+ * that inherits Item for example will have all its fields accessible directly,
+ * e.g. `JokerObject joker_object; joker_object.type = ITEM_TYPE_JOKER`
+ */
+typedef struct Item
+{
+    /**
+     * @brief First member struct inheritance
+     * all items that can appear in the shop are SpriteObjects.
+     * Note that this is an anonymous member.
+     */
+    SpriteObject;
+
+    /**
+     * @brief The item type - used to dispatch the function implementations for inheriting types.
+     */
+    enum ItemType type;
+} Item;
+
+/**
+ * @brief The set of functions that each item type implements.
+ */
+typedef struct ItemFuncs
+{
+    /**
+     * All items must implement the following since they are called by the shop and all items
+     * must be capable of appearing in the shop.
+     */
+    Item* (*roll_new)(void);
+    int (*get_buy_price)(Item* item);
+    bool (*can_acquire)(Item* item);
+    void (*acquire)(Item* item);
+    void (*dispose)(Item** item);
+    // TODO: void (*print_description)(Item* item); // or something of the form
+
+    // Optional implementation functions will be added here
+} ItemFuncs;
+
+/**
+ * @brief Rolls a random item of type @p item_type and returns a newly created one.
+ * Manages rollable items set if necessary (i.e. not rolling items already in inventory)
+ * To be used when rolling new items for the shop or packs.
+ *
+ * Matches @ref ItemFuncs.roll_new()
+ *
+ * @param item_type The type of the item to roll
+ *
+ * @return The newly created randomly rolled item
+ */
+Item* item_roll_new(enum ItemType item_type);
+
+/**
+ * @brief Returns the buy price of the item.
+ *
+ * Matches @ref ItemFuncs.get_buy_price()
+ *
+ * @param item The item whose price to return.
+ *
+ * @return UNDEFINED in case of error, the item's buy price otherwise.
+ */
+int item_get_buy_price(Item* item);
+
+/**
+ * @brief Acquires the item, adding to inventory if applicable.
+ * Called when it is purchased from the shop, note that it does not
+ * perform the purchase operation of decrementing the player's money,
+ * that should be handled by the shop code.
+ * For packs this can be to just open the pack,
+ * for vouchers, this will apply their effect.
+ *
+ * Matches @ref ItemFuncs.acquire()
+ *
+ * @param item The item to acquire
+ */
+void item_acquire(Item* item);
+
+/**
+ * @brief Returns true if the item can be acquired, i.e. added to inventory.
+ * Does not check if the player has enough money to buy the item, that is the shop's job,
+ * as this will be used both when purchasing and when selecting in a pack.
+ *
+ * Matches @ref ItemFuncs.can_acquire()
+ *
+ * @param item The item to check
+ */
+bool item_can_acquire(Item* item);
+
+/**
+ * @brief Destroys an item, freeing underlying resources, and manages rollable items sets if needed.
+ * To be used when destroying items from the inventory, shop, or packs.
+ *
+ * @param item A pointer to an item for destruction.
+ */
+void item_dispose(Item** item);
+
+/**
+ * @brief Prints the buy price under the item
+ * Relies on the fact item is a SpriteObject
+ *
+ * @param item The item to print under
+ */
+void item_print_buy_price_under(Item* item);
+
+#endif // ITEM_H

include/item_funcs.h

@@ -0,0 +1,26 @@
+/**
+ * @file item_funcs.h
+ *
+ * @brief An API for the item functions defined in item.h
+ * Separated module from item.c/.h so item_funcs.c can include joker.h and card.h etc.
+ * so the item.h doesn't depend on implementations such as jokers and cards.
+ */
+
+#ifndef ITEM_FUNCS_H
+#define ITEM_FUNCS_H
+
+#include "item.h"
+
+/**
+ * @brief Returns the function table for a given item type.
+ *
+ * Looks up the @ref ItemFuncs dispatch table corresponding to @p type.
+ *
+ * @param type The item type whose function table to retrieve.
+ *
+ * @return Pointer to the @ref ItemFuncs table for @p type,
+ *         or NULL if @p type is invalid or has no implemented functions.
+ */
+ItemFuncs* get_item_type_funcs(enum ItemType type);
+
+#endif // ITEM_FUNCS_H

include/joker.h

@@ -9,7 +9,7 @@
 #include "card.h"
 #include "game.h"
 #include "graphic_utils.h"
-#include "sprite.h"
+#include "item.h"
 
 #include <maxmod.h>
 
@@ -112,8 +112,8 @@ typedef struct
 
 typedef struct JokerObject
 {
+    Item; // First member struct inheritance
     Joker* joker;
-    SpriteObject* sprite_object;
 } JokerObject;
 
 typedef struct // These jokers are triggered after the played hand has finished scoring.
@@ -197,6 +197,51 @@ JokerObject* joker_object_new(Joker* joker);
 void joker_object_destroy(JokerObject** joker_object);
 // This doesn't actually score anything, it just performs an animation and plays a sound effect
 void joker_object_shake(JokerObject* joker_object, mm_word sound_id);
+
+/**
+ * @brief Returns the buy price of the joker object.
+ *
+ * @param joker_object the joker object whose price to return.
+ *
+ * @return UNDEFINED in case of error, the buy price of the joker otherwise.
+ */
+int joker_object_get_buy_price(Item* joker_object);
+
+// TODO: Move to an owned_jokers.c/.h file?
+/**
+ * @brief Add a Joker to the list of owned Jokers and place it in the joker row.
+ *
+ * @param joker_object The JokerObject to add cast to Item*
+ */
+void joker_object_add_to_owned(Item* joker_object);
+
+/**
+ * @brief Destroy a JokerObject item, free its resources, and make it available to be rolled.
+ *
+ * @param joker_object Pointer to the JokerObject Item* to destroy; set to NULL.
+ */
+void joker_object_dispose(Item** joker_object);
+
+/**
+ * @brief Set whether a Joker is available to be rolled for the shop, packs, etc.
+ *
+ * @param joker_id The ID of the joker whose availability to set.
+ * @param rollable true to make it rollable, false otherwise.
+ */
+void joker_set_rollable(int joker_id, bool rollable);
+
+/**
+ * @brief Reset rollable jokers to include all jokers in the registry.
+ */
+void joker_reset_rollable_jokers(void);
+
+/**
+ * @brief Roll and create a new JokerObject item.
+ *
+ * @return Newly created `Item*` (JokerObject) or NULL if none available.
+ */
+Item* joker_object_roll_new(void);
+
 // This scores the joker and returns true if it was scored successfully
 // card_object = NULL means the joker_event does not concern a particular Card, i.e. Independend or
 // On_Blind_Selected as opposed to events that concern a particular card, i.e. On_Card_Scored or

include/sprite.h

@@ -194,23 +194,24 @@ void sprite_init(void);
 void sprite_draw(void);
 
 /**
- * @brief Allocate and retrieve a pointer to a valid SpriteObject
+ * @brief Initialize a SpriteObject to a default state.
+ * Must be called only once per SpriteObject when it is created.
  *
- * @return A valid pointer to an newly allocated SpriteObject
- *         if successful, othewise return **NULL**.
+ * @param sprite_object - The SpriteObject to initialize
  */
-SpriteObject* sprite_object_new();
+void sprite_object_init(SpriteObject* sprite_object);
 
 /**
  * @brief Destroy SpriteObject
  *
- * Destroy a SpriteObject by freeing it back to the pool and releasing its
- * associated resources
+ * Destroy a SpriteObject by releasing its associated resources (e.g. the sprite).
+ * This invalidates the SpriteObject and it should not be used after destroyed,
+ * a new one should be created instead.
  *
- * @param sprite_object pointer to a pointer of SpriteObject to destroy.
+ * @param sprite_object pointer to a SpriteObject to destroy.
  *        Cannot be **NULL**.
  */
-void sprite_object_destroy(SpriteObject** sprite_object);
+void sprite_object_destroy(SpriteObject* sprite_object);
 
 /**
  * @brief Register a Sprite to an associated SpriteObject

source/card.c

@@ -1,6 +1,8 @@
 #include "card.h"
 
 #include "graphic_utils.h"
+#include "item.h"
+#include "util.h"
 
 #include <maxmod.h>
 #include <stdlib.h>
@@ -101,9 +103,10 @@ u8 card_get_value(Card* card)
 CardObject* card_object_new(Card* card)
 {
     CardObject* card_object = POOL_GET(CardObject);
-
+    sprite_object_init((SpriteObject*)card_object);
     card_object->card = card;
-    card_object->sprite_object = sprite_object_new();
+
+    card_object->type = ITEM_TYPE_PLAYING_CARD;
     card_object->selected = false;
 
     return card_object;
@@ -113,7 +116,7 @@ void card_object_destroy(CardObject** card_object)
 {
     if (*card_object == NULL)
         return;
-    sprite_object_destroy(&((*card_object)->sprite_object));
+    sprite_object_destroy((SpriteObject*)(*card_object));
     POOL_FREE(CardObject, *card_object);
     *card_object = NULL;
 }
@@ -134,7 +137,7 @@ void card_object_set_sprite(CardObject* card_object, int layer)
         CARD_PB,
         layer + CARD_STARTING_LAYER
     );
-    sprite_object_set_sprite(card_object->sprite_object, sprite);
+    sprite_object_set_sprite((SpriteObject*)card_object, sprite);
 }
 
 void card_object_set_sprite_face_down(CardObject* card_object, enum DeckType deck, int layer)
@@ -152,12 +155,12 @@ void card_object_set_sprite_face_down(CardObject* card_object, enum DeckType dec
         DECK_SPRITES_PB,
         layer + CARD_STARTING_LAYER
     );
-    sprite_object_set_sprite(card_object->sprite_object, sprite);
+    sprite_object_set_sprite((SpriteObject*)card_object, sprite);
 }
 
 void card_object_shake(CardObject* card_object, mm_word sound_id)
 {
-    sprite_object_shake(card_object->sprite_object, sound_id);
+    sprite_object_shake((SpriteObject*)card_object, sound_id);
 }
 
 void card_object_set_selected(CardObject* card_object, bool selected)
@@ -178,5 +181,24 @@ Sprite* card_object_get_sprite(CardObject* card_object)
 {
     if (card_object == NULL)
         return NULL;
-    return sprite_object_get_sprite(card_object->sprite_object);
+    return sprite_object_get_sprite((SpriteObject*)card_object);
+}
+
+int card_object_get_buy_price(Item* card_object)
+{
+    GBAL_RETURN_IF_NULL_RET(card_object, UNDEFINED);
+    ITEM_RETURN_IF_UNEXPECTED_TYPE_RET(card_object, ITEM_TYPE_PLAYING_CARD, UNDEFINED);
+
+    return 1;
+}
+
+void card_object_dispose(Item** card_object_item)
+{
+    GBAL_RETURN_IF_NULL_VOID(card_object_item);
+    GBAL_RETURN_IF_NULL_VOID(*card_object_item);
+    ITEM_RETURN_IF_UNEXPECTED_TYPE_VOID(*card_object_item, ITEM_TYPE_PLAYING_CARD);
+
+    CardObject* card_object = (CardObject*)(*card_object_item);
+    card_object_destroy(&card_object);
+    *card_object_item = NULL;
 }

source/game.c

@@ -253,10 +253,10 @@ static inline void discarded_jokers_update_loop(void)
 
     while ((joker_object = list_itr_next(&itr)))
     {
-        if (joker_object->sprite_object->x == joker_object->sprite_object->tx &&
-            joker_object->sprite_object->y == joker_object->sprite_object->ty)
+        if (joker_object->x == joker_object->tx && joker_object->y == joker_object->ty)
         {
             list_itr_remove_current_node(&itr);
+            // TODO: joker_object_dispose() instead?
             joker_object_destroy(&joker_object);
         }
     }
@@ -282,11 +282,17 @@ static inline void held_jokers_update_loop(void)
     {
         // Let the Shop handle the position of this Joker
         if (joker != game_shop_get_description_card())
-            joker->sprite_object->tx = hand_x - int2fx(spacing_lut[jokers_top][i]);
+            joker->tx = hand_x - int2fx(spacing_lut[jokers_top][i]);
         i++;
     }
 }
 
+bool joker_object_can_acquire(Item* joker_object)
+{
+    GBAL_RETURN_IF_NULL_RET(joker_object, false);
+    return (list_get_len(get_jokers_list()) < MAX_JOKERS_HELD_SIZE);
+}
+
 static inline void expired_jokers_update_loop(void)
 {
     if (list_is_empty(&_expired_jokers_list))
@@ -429,7 +435,8 @@ void remove_owned_joker(int owned_joker_idx)
         shortcut_joker_count--;
     }
 
-    game_shop_set_joker_avail(joker_object->joker->id, true);
+    // TODO: Move to site of joker_destroy()?
+    joker_set_rollable(joker_object->joker->id, true);
     list_remove_at_idx(&_owned_jokers_list, owned_joker_idx);
 }
 

source/game/game_over.c

@@ -143,7 +143,7 @@ static void game_over_common_init(enum EndCondition init_condition)
     ListItr itr = list_itr_create(get_jokers_list());
     while ((joker_object = list_itr_next(&itr)))
     {
-        obj_hide(joker_object->sprite_object->sprite->obj);
+        obj_hide(joker_object->sprite->obj);
     }
 
     // Destroy any preexisting cards in the deck, which will be present if we restart a run

source/game/joker_row.c

@@ -33,8 +33,8 @@ bool jokers_sel_row_on_selection_changed(
         // Don't change focus from current Joker if swapping
         if (joker_object != NULL && !swapping)
         {
-            sprite_object_erase_text_under(joker_object->sprite_object);
-            sprite_object_set_focus(joker_object->sprite_object, false);
+            sprite_object_erase_text_under((SpriteObject*)joker_object);
+            sprite_object_set_focus((SpriteObject*)joker_object, false);
         }
     }
 
@@ -46,7 +46,7 @@ bool jokers_sel_row_on_selection_changed(
         {
             if (!swapping)
             {
-                sprite_object_set_focus(joker_object->sprite_object, true);
+                sprite_object_set_focus((SpriteObject*)joker_object, true);
             }
             // If we land on this row while the A button is being held, we are in swapping mode
             // This means that we need to hide the price, whether we were already
@@ -54,7 +54,7 @@ bool jokers_sel_row_on_selection_changed(
             if (!key_is_down(SELECT_CARD))
             {
                 sprite_object_print_price_under(
-                    joker_object->sprite_object,
+                    (SpriteObject*)joker_object,
                     joker_get_sell_value(joker_object->joker)
                 );
             }
@@ -75,8 +75,8 @@ bool jokers_sel_row_on_selection_changed(
 
 static inline void joker_start_discard_animation(JokerObject* joker_object)
 {
-    joker_object->sprite_object->tx = int2fx(JOKER_DISCARD_TARGET.x);
-    joker_object->sprite_object->ty = int2fx(JOKER_DISCARD_TARGET.y);
+    joker_object->tx = int2fx(JOKER_DISCARD_TARGET.x);
+    joker_object->ty = int2fx(JOKER_DISCARD_TARGET.y);
     list_push_back(get_discarded_jokers_list(), joker_object);
 }
 
@@ -90,7 +90,7 @@ static inline void game_sell_joker(int joker_idx)
     JokerObject* joker_object = (JokerObject*)list_get_at_idx(owned_jokers_list, joker_idx);
     g_game_vars.money += joker_get_sell_value(joker_object->joker);
     display_money();
-    sprite_object_erase_text_under(joker_object->sprite_object);
+    sprite_object_erase_text_under((SpriteObject*)joker_object);
 
     remove_owned_joker(joker_idx);
 
@@ -104,12 +104,12 @@ void jokers_sel_row_on_key_transit(SelectionGrid* selection_grid, Selection* sel
     {
         if (key_hit(SELECT_CARD))
         {
-            sprite_object_erase_text_under(joker_object->sprite_object);
+            sprite_object_erase_text_under((SpriteObject*)joker_object);
         }
         else if (key_released(SELECT_CARD))
         {
             sprite_object_print_price_under(
-                joker_object->sprite_object,
+                (SpriteObject*)joker_object,
                 joker_get_sell_value(joker_object->joker)
             );
         }

source/game/main_menu.c

@@ -105,9 +105,10 @@ void game_main_menu_on_init(void)
     change_background(BG_MAIN_MENU, true);
     main_menu_ace = card_object_new(card_new(SPADES, ACE));
     card_object_set_sprite(main_menu_ace, 0);
-    main_menu_ace->sprite_object->sprite->obj->attr0 |= ATTR0_AFF_DBL;
-    main_menu_ace->sprite_object->tscale = float2fx(0.8f);
-    sprite_object_position(main_menu_ace->sprite_object, MAIN_MENU_ACE_T_X, MAIN_MENU_ACE_T_Y);
+    // TODO: NULL-check sprite
+    main_menu_ace->sprite->obj->attr0 |= ATTR0_AFF_DBL;
+    main_menu_ace->tscale = float2fx(0.8f);
+    sprite_object_position((SpriteObject*)main_menu_ace, MAIN_MENU_ACE_T_X, MAIN_MENU_ACE_T_Y);
 
     // Select last highlighted button, Play button by default.
     // e.g. if we return from the options menu, we want the Options button to be highlighted.
@@ -120,7 +121,7 @@ void game_main_menu_on_init(void)
 
 void game_main_menu_on_update(void)
 {
-    main_menu_ace->sprite_object->trotation = lu_sin((g_game_vars.timer << 8) / 2) / 3;
+    main_menu_ace->trotation = lu_sin((g_game_vars.timer << 8) / 2) / 3;
 
     selection_grid_process_input(&main_menu_selection_grid);
 }

source/game/round.c

@@ -783,7 +783,7 @@ static inline void card_in_hand_loop_handle_discard_and_shuffling(
                 sound_played = true;
             }
 
-            if (hand[card_idx]->sprite_object->x >= *hand_x)
+            if (hand[card_idx]->x >= *hand_x)
             {
                 discard_push(hand[card_idx]->card);
 
@@ -801,8 +801,8 @@ static inline void card_in_hand_loop_handle_discard_and_shuffling(
                 // and we end up with an element at `card_idx` that is still NULL.
                 if (hand[card_idx] != NULL)
                 {
-                    *hand_y = hand[card_idx]->sprite_object->y;
-                    *hand_x = hand[card_idx]->sprite_object->x;
+                    *hand_y = hand[card_idx]->y;
+                    *hand_x = hand[card_idx]->x;
                 }
             }
 
@@ -1138,8 +1138,8 @@ static inline void card_draw(void)
     const FIXED deck_x = int2fx(CARD_DRAW_POS.x);
     const FIXED deck_y = int2fx(CARD_DRAW_POS.y);
 
-    card_object->sprite_object->x = deck_x;
-    card_object->sprite_object->y = deck_y;
+    card_object->x = deck_x;
+    card_object->y = deck_y;
 
     set_hand_top(get_hand_top() + 1);
     get_hand_array()[get_hand_top()] = card_object;
@@ -1190,16 +1190,16 @@ static inline void game_round_discarded_cards_loop(void)
 
             // Set the sprite for the discarded card object
             card_object_set_sprite(discarded_card_object, 0);
-            sprite_object_reset_transform(discarded_card_object->sprite_object);
+            sprite_object_reset_transform((SpriteObject*)discarded_card_object);
 
-            discarded_card_object->sprite_object->tx = int2fx(204);
-            discarded_card_object->sprite_object->ty = int2fx(112);
-            discarded_card_object->sprite_object->x = int2fx(240);
-            discarded_card_object->sprite_object->y = int2fx(80);
+            discarded_card_object->tx = int2fx(204);
+            discarded_card_object->ty = int2fx(112);
+            discarded_card_object->x = int2fx(240);
+            discarded_card_object->y = int2fx(80);
         }
         else
         {
-            if (discarded_card_object->sprite_object->y >= discarded_card_object->sprite_object->ty)
+            if (discarded_card_object->y >= discarded_card_object->ty)
             {
                 deck_push(discarded_card_object->card); // Put the card back into the deck
                 card_object_destroy(&discarded_card_object);
@@ -1301,13 +1301,13 @@ static inline void cards_in_hand_update_loop(void)
                     {
                         hand_y -= int2fx(CARD_FOCUSED_SEL_Y);
                     }
-                    if (i != selected_card_idx && hand[i]->sprite_object->y > hand_y)
+                    if (i != selected_card_idx && hand[i]->y > hand_y)
                     {
-                        hand[i]->sprite_object->y = hand_y;
+                        hand[i]->y = hand_y;
                         // Set target y to match y. Ensures target is updated even when vy becomes
                         // 0, preventing immediate snap back.
-                        hand[i]->sprite_object->ty = hand_y;
-                        hand[i]->sprite_object->vy = 0;
+                        hand[i]->ty = hand_y;
+                        hand[i]->vy = 0;
                     }
 
                     hand_x = hand_x + (int2fx(i) - int2fx(get_hand_top()) / 2) *
@@ -1339,7 +1339,7 @@ static inline void cards_in_hand_update_loop(void)
                     {
                         card_object_set_selected(hand[i], false);
                         played_push(hand[i]);
-                        sprite_destroy(&hand[i]->sprite_object->sprite);
+                        sprite_destroy(&hand[i]->sprite);
                         hand[i] = NULL;
                         reorder_card_sprites_layers();
 
@@ -1376,8 +1376,8 @@ static inline void cards_in_hand_update_loop(void)
                     break;
             }
 
-            hand[i]->sprite_object->tx = hand_x;
-            hand[i]->sprite_object->ty = hand_y;
+            hand[i]->tx = hand_x;
+            hand[i]->ty = hand_y;
         }
     }
 }
@@ -1526,14 +1526,14 @@ static inline void play_starting_played_cards_update(int played_idx)
         }
     }
 
-    played[played_idx]->sprite_object->tx =
+    played[played_idx]->tx =
         int2fx(HAND_PLAY_POS.x) + (int2fx(played_top - played_idx) - int2fx(played_top) / 2) * -27;
-    played[played_idx]->sprite_object->ty = int2fx(HAND_PLAY_POS.y);
+    played[played_idx]->ty = int2fx(HAND_PLAY_POS.y);
 
     card_selected = card_object_is_selected(played[played_idx]);
     if (card_selected && played_top - played_idx >= scored_card_index)
     {
-        played[played_idx]->sprite_object->ty -= int2fx(10);
+        played[played_idx]->ty -= int2fx(10);
     }
 }
 
@@ -1593,10 +1593,7 @@ static inline bool play_scoring_cards_update(void)
         if (card_object_is_selected(scored_card_object))
         {
             // Offset of 1 tile to keep the text on the card
-            tte_set_pos(
-                fx2int(scored_card_object->sprite_object->x) + TILE_SIZE,
-                SCORED_CARD_TEXT_Y
-            );
+            tte_set_pos(fx2int(scored_card_object->x) + TILE_SIZE, SCORED_CARD_TEXT_Y);
 
             // Set text color to blue from background memory
             tte_set_special(TTE_BLUE_PB * TTE_SPECIAL_PB_MULT_OFFSET);
@@ -1809,7 +1806,7 @@ static inline void play_ending_played_cards_update(int played_idx)
 
     if (card_object_is_selected(played[played_idx]) && played_top - played_idx >= scored_card_index)
     {
-        played[played_idx]->sprite_object->ty = int2fx(HAND_PLAY_POS.y);
+        played[played_idx]->ty = int2fx(HAND_PLAY_POS.y);
     }
 }
 
@@ -1837,7 +1834,7 @@ static bool play_ended_played_cards_update(int played_idx)
         }
 
         // card has exited the screen, now discard it and set it to NULL
-        if (played[played_idx]->sprite_object->x >= int2fx(CARD_DISCARD_PNT.x))
+        if (played[played_idx]->x >= int2fx(CARD_DISCARD_PNT.x))
         {
             discard_push(played[played_idx]->card); // Push the card to the discard pile
             card_object_destroy(&played[played_idx]);
@@ -1870,7 +1867,7 @@ static bool play_ended_played_cards_update(int played_idx)
         }
 
         // put target X position off screen to the right
-        played[played_idx]->sprite_object->tx = int2fx(CARD_DISCARD_PNT.x);
+        played[played_idx]->tx = int2fx(CARD_DISCARD_PNT.x);
         discarded_card = true;
     }
 
@@ -1968,7 +1965,7 @@ static inline void played_cards_update_loop(void)
                 break;
         }
 
-        played[played_idx]->sprite_object->tscale = FIX_ONE;
+        played[played_idx]->tscale = FIX_ONE;
     }
 }
 

source/game/run_setup.c

@@ -602,7 +602,7 @@ void game_run_setup_on_init(void)
     card_object_set_sprite_face_down(run_setup_deck, g_game_vars.deck, 0);
 
     sprite_object_position(
-        run_setup_deck->sprite_object,
+        (SpriteObject*)run_setup_deck,
         RUN_SETUP_DECK_SPRITE_T_X,
         RUN_SETUP_DECK_SPRITE_T_Y
     );
@@ -650,7 +650,13 @@ void game_run_setup_on_exit(void)
 static void choose_deck_substate_init(void)
 {
     // Show Deck sprite, name and TODO: description
-    obj_unhide(run_setup_deck->sprite_object->sprite->obj, ATTR0_AFF);
+    {
+        Sprite* deck_sprite = sprite_object_get_sprite((SpriteObject*)run_setup_deck);
+        if (deck_sprite != NULL)
+        {
+            obj_unhide(deck_sprite->obj, ATTR0_AFF);
+        }
+    }
     print_deck_name(g_game_vars.deck, RUN_SETUP_DECK_NAME_TEXT_POS);
     print_deck_description(g_game_vars.deck, RUN_SETUP_DECK_DESC_TEXT_POS);
 
@@ -815,7 +821,13 @@ static void seed_keyboard_substate_init(void)
     tte_erase_rect_wrapper(RUN_SETUP_DECK_NAME_DESC_RECT);
 
     // Hide Deck card sprite
-    obj_hide(run_setup_deck->sprite_object->sprite->obj);
+    {
+        Sprite* deck_sprite = sprite_object_get_sprite((SpriteObject*)run_setup_deck);
+        if (deck_sprite != NULL)
+        {
+            obj_hide(deck_sprite->obj);
+        }
+    }
 
     // Clean deck swap screen with frame BG color
     main_bg_se_copy_expand_tile(
@@ -1110,7 +1122,13 @@ static void resume_substate_init(void)
     tab_set_highlight(RUN_SETUP_TAB_RESUME);
 
     // Show Deck card sprite
-    obj_unhide(run_setup_deck->sprite_object->sprite->obj, ATTR0_AFF);
+    {
+        Sprite* deck_sprite = sprite_object_get_sprite((SpriteObject*)run_setup_deck);
+        if (deck_sprite != NULL)
+        {
+            obj_unhide(deck_sprite->obj, ATTR0_AFF);
+        }
+    }
 }
 
 // COMMON BUTTONS

source/game/shop.c

@@ -17,6 +17,7 @@
 #include "joker.h"
 #include "layout.h"
 #include "list.h"
+#include "mgba_logger.h"
 #include "random.h"
 #include "save.h"
 #include "soundbank.h"
@@ -87,8 +88,7 @@ static const Rect     SHOP_PRICES_TEXT_RECT       = { 72,  56, 192, 160 };
 static const Rect     SHOP_REROLL_RECT            = { 88,  96, UNDEFINED, UNDEFINED };
 // clang-format on
 
-static List s_shop_jokers_list = LIST_DEFAULT;
-BITSET_DEFINE(s_avail_jokers_bitset, MAX_DEFINABLE_JOKERS)
+static List s_shop_items_list = LIST_DEFAULT;
 
 enum GameShopStates
 {
@@ -170,6 +170,8 @@ static int timer;
 static int reroll_cost = REROLL_BASE_COST;
 
 // Variables relative to the Card we are showing the description of
+
+// TODO: Change this to item once it has description printing API.
 static JokerObject* description_card = NULL;
 static FIXED description_card_original_x_pos = UNDEFINED;
 static FIXED description_card_original_y_pos = UNDEFINED;
@@ -180,30 +182,11 @@ JokerObject* game_shop_get_description_card(void)
     return description_card;
 }
 
-static inline void reset_shop_jokers(void)
-{
-    int num_jokers = get_joker_registry_size();
-
-    bitset_clear(&s_avail_jokers_bitset);
-    for (int i = 0; i < num_jokers; i++)
-    {
-        bitset_set_idx(&s_avail_jokers_bitset, i, true);
-    }
-}
-
 void game_shop_reset(void)
 {
-    list_clear(&s_shop_jokers_list);
-    s_shop_jokers_list = list_init();
-    reset_shop_jokers();
-}
-
-/**
- * @brief Set whether a Joker can appear in the shop.
- */
-void game_shop_set_joker_avail(int joker_id, bool avail)
-{
-    bitset_set_idx(&s_avail_jokers_bitset, joker_id, avail);
+    list_clear(&s_shop_items_list);
+    s_shop_items_list = list_init();
+    joker_reset_rollable_jokers();
 }
 
 void game_shop_change_background(void)
@@ -246,123 +229,51 @@ void game_shop_on_init(void)
 }
 
 /**
- * @brief Computes the number of Jokers we can currently roll in the Shop.
- *         The Jokers we own is taken into account and can't be rolled again.
+ * @brief Create a shop top row item - jokers, consumables, and possibly playing cards
+ * Currently only jokers are implemented.
  */
-static inline int get_num_shop_jokers_avail(void)
+static Item* game_shop_create_top_row_item(void)
 {
-    return bitset_num_set_bits(&s_avail_jokers_bitset);
+    // TODO: Randomize item type when consumables are implemented
+    return item_roll_new(ITEM_TYPE_JOKER);
 }
 
 /**
- * @brief Rolls a random Joker among the available ones
+ * @brief Setup for the lists of items we can purchase in the top row of the Shop.
+ *        i.e. Jokers and consumables and possibly playing cards.
  */
-static inline int game_shop_get_rand_available_joker_id(void)
-{
-    // Roll for what rarity the joker will be
-    int joker_rarity = joker_get_random_rarity();
-
-    // Now determine how many jokers are available based on the rarity
-    int jokers_avail_size = get_num_shop_jokers_avail();
-
-    if (jokers_avail_size == 0)
-        return UNDEFINED;
-
-    int matching_joker_ids[jokers_avail_size];
-    int fallback_random_idx = rng_get_u32() % jokers_avail_size;
-    int fallback_random_joker_id = UNDEFINED;
-    int match_count = 0;
-
-    BitsetItr itr = bitset_itr_create(&s_avail_jokers_bitset);
-
-    int i = 0;
-    int joker_id = UNDEFINED;
-    while ((joker_id = bitset_itr_next(&itr)) != UNDEFINED)
-    {
-        if (i++ == fallback_random_idx)
-            fallback_random_joker_id = joker_id;
-        const JokerInfo* info = get_joker_registry_entry(joker_id);
-        if (info->rarity == joker_rarity)
-        {
-            matching_joker_ids[match_count++] = joker_id;
-        }
-    }
-
-    int selected_joker_id = (match_count > 0) ? matching_joker_ids[rng_get_u32() % match_count]
-                                              : fallback_random_joker_id;
-
-    return selected_joker_id;
-}
-
-/**
- * @brief Returns true if we can't roll any Joker
- */
-static inline bool no_avail_jokers(void)
-{
-    return bitset_is_empty(&s_avail_jokers_bitset);
-}
-
-GBAL_UNUSED
-static inline bool is_shop_joker_avail(int joker_id)
-{
-    return bitset_get_idx(&s_avail_jokers_bitset, joker_id);
-}
-
-/**
- * @brief Setup for the lists of items we can purchase in the Shop.
- *         Only Jokers are available for now, but this is where consumables and
- *         booster packs will be rolled when they are implemented.
- */
-static void game_shop_create_items(void)
+static void game_shop_create_top_row_items(void)
 {
     tte_erase_rect_wrapper(SHOP_PRICES_TEXT_RECT);
 
-    if (no_avail_jokers())
-        return;
+    List* shop_items_list = &s_shop_items_list;
 
-    List* shop_jokers_list = &s_shop_jokers_list;
+    list_clear(shop_items_list);
+    *shop_items_list = list_init();
 
-    list_clear(shop_jokers_list);
-    *shop_jokers_list = list_init();
-
-    for (int i = 0; i < MAX_SHOP_JOKERS; i++)
+    for (int i = 0; i < MAX_SHOP_ITEMS; i++)
     {
-        int joker_id = 0;
-#ifdef TEST_JOKER_ID0 // Allow defining an ID for a joker to always appear in shop and be tested
-        if (is_shop_joker_avail(TEST_JOKER_ID0))
+        Item* item = game_shop_create_top_row_item();
+
+        if (item == NULL)
         {
-            joker_id = TEST_JOKER_ID0;
-        }
-        else
-#endif
-#ifdef TEST_JOKER_ID1
-            if (is_shop_joker_avail(TEST_JOKER_ID1))
-        {
-            joker_id = TEST_JOKER_ID1;
-        }
-        else
-#endif
-        {
-            joker_id = game_shop_get_rand_available_joker_id();
+            MGBA_FUNC_WARN("Could not create shop item");
+
+            // TODO: Decide how to handle this case gracefully
+            // If the issue for example is that we can't generate any more jokers,
+            // because for example the user owns all of them,
+            // maybe we need to generate consumables instead.
+            return;
         }
 
-        // If for some reason only no joker is left, don't make another
-        if (joker_id == UNDEFINED)
-            break;
+        item->x = int2fx(SHOP_JOKER_SPRITES_INIT_POS.x + i * CARD_SPRITE_SIZE);
+        item->y = int2fx(SHOP_JOKER_SPRITES_INIT_POS.y);
+        item->tx = item->x;
+        item->ty = int2fx(ITEM_SHOP_Y);
 
-        game_shop_set_joker_avail(joker_id, false);
+        item_print_buy_price_under(item);
 
-        JokerObject* joker_object = joker_object_new(joker_new(joker_id));
-
-        joker_object->sprite_object->x =
-            int2fx(SHOP_JOKER_SPRITES_INIT_POS.x + i * CARD_SPRITE_SIZE);
-        joker_object->sprite_object->y = int2fx(SHOP_JOKER_SPRITES_INIT_POS.y);
-        joker_object->sprite_object->tx = joker_object->sprite_object->x;
-        joker_object->sprite_object->ty = int2fx(ITEM_SHOP_Y);
-
-        sprite_object_print_price_under(joker_object->sprite_object, joker_object->joker->value);
-
-        list_push_back(shop_jokers_list, joker_object);
+        list_push_back(shop_items_list, item);
     }
 }
 
@@ -375,7 +286,7 @@ static void game_shop_intro()
 
     if (timer == TM_CREATE_SHOP_ITEMS_WAIT)
     {
-        game_shop_create_items();
+        game_shop_create_top_row_items();
     }
 
     if (timer >= TM_SHIFT_SHOP_ICON_WAIT) // Shift the shop icon
@@ -419,32 +330,23 @@ static void game_shop_intro()
 static int shop_top_row_get_size(void)
 {
     // + 1 to account for next round button
-    return list_get_len(&s_shop_jokers_list) + 1;
-}
-
-/**
- * @brief Add a newly purchased Joker to the list of owned Jokers.
- */
-static inline void add_to_held_jokers(JokerObject* joker_object)
-{
-    joker_object->sprite_object->ty = int2fx(HELD_JOKERS_POS.y);
-    add_joker(joker_object);
+    return list_get_len(&s_shop_items_list) + 1;
 }
 
 /**
  * @brief Called when pressing A on a Shop Joker to buy it.
  */
-static inline void game_shop_buy_joker(int shop_joker_idx)
+static inline void game_shop_buy_item(int shop_item_idx)
 {
-    List* shop_jokers_list = &s_shop_jokers_list;
-    JokerObject* joker_object = (JokerObject*)list_get_at_idx(shop_jokers_list, shop_joker_idx);
+    List* shop_items_list = &s_shop_items_list;
+    Item* item = (Item*)list_get_at_idx(shop_items_list, shop_item_idx);
 
-    g_game_vars.money -= joker_object->joker->value;
+    g_game_vars.money -= item_get_buy_price(item);
     display_money();
-    sprite_object_erase_text_under(joker_object->sprite_object);
-    sprite_object_set_focus(joker_object->sprite_object, false);
-    add_to_held_jokers(joker_object);
-    list_remove_at_idx(shop_jokers_list, shop_joker_idx); // Remove the joker from the shop
+    sprite_object_erase_text_under((SpriteObject*)item);
+    sprite_object_set_focus((SpriteObject*)item, false);
+    item_acquire(item);
+    list_remove_at_idx(shop_items_list, shop_item_idx); // Remove the joker from the shop
 }
 
 /**
@@ -461,16 +363,14 @@ static void shop_top_row_on_key_transit(SelectionGrid* selection_grid, Selection
     }
     else
     {
-        int shop_joker_idx = selection->x - 1; // - 1 to account for next round button
-        JokerObject* joker_object =
-            (JokerObject*)list_get_at_idx(&s_shop_jokers_list, shop_joker_idx);
-        if (joker_object == NULL || list_get_len(get_jokers_list()) >= MAX_JOKERS_HELD_SIZE ||
-            g_game_vars.money < joker_object->joker->value)
+        int shop_item_idx = selection->x - 1; // - 1 to account for next round button
+        Item* item = (Item*)list_get_at_idx(&s_shop_items_list, shop_item_idx);
+        if (!item_can_acquire(item) || g_game_vars.money < item_get_buy_price(item))
         {
             return;
         }
 
-        game_shop_buy_joker(shop_joker_idx);
+        game_shop_buy_item(shop_item_idx);
         selection_grid_move_selection_horz(selection_grid, -1);
     }
 }
@@ -485,7 +385,7 @@ static bool shop_top_row_on_selection_changed(
     const Selection* new_selection
 )
 {
-    List* shop_jokers_list = &s_shop_jokers_list;
+    List* shop_items_list = &s_shop_items_list;
     // Guard if we move down while on jokers
     if (new_selection->y > row_idx && prev_selection->x > 0)
         return false;
@@ -503,8 +403,8 @@ static bool shop_top_row_on_selection_changed(
         else
         {
             int idx = prev_selection->x - 1; // -1 to account for next round button
-            JokerObject* joker_object = (JokerObject*)list_get_at_idx(shop_jokers_list, idx);
-            sprite_object_set_focus(joker_object->sprite_object, false);
+            SpriteObject* sprite_object = (SpriteObject*)list_get_at_idx(shop_items_list, idx);
+            sprite_object_set_focus(sprite_object, false);
         }
     }
 
@@ -517,8 +417,8 @@ static bool shop_top_row_on_selection_changed(
         else
         {
             int idx = new_selection->x - 1; // -1 to account for next round button
-            JokerObject* joker_object = (JokerObject*)list_get_at_idx(shop_jokers_list, idx);
-            sprite_object_set_focus(joker_object->sprite_object, true);
+            SpriteObject* sprite_object = (SpriteObject*)list_get_at_idx(shop_items_list, idx);
+            sprite_object_set_focus(sprite_object, true);
         }
     }
 
@@ -552,8 +452,8 @@ static bool shop_reroll_row_on_selection_changed(
         if (new_selection->x != NEXT_ROUND_BTN_SEL_X)
         {
             int idx = new_selection->x - 1;
-            JokerObject* joker_object = (JokerObject*)list_get_at_idx(&s_shop_jokers_list, idx);
-            sprite_object_set_focus(joker_object->sprite_object, true);
+            SpriteObject* sprite_object = (SpriteObject*)list_get_at_idx(&s_shop_items_list, idx);
+            sprite_object_set_focus(sprite_object, true);
         }
     }
     else if (row_idx == new_selection->y)
@@ -573,35 +473,33 @@ static inline void game_shop_reroll(void)
     g_game_vars.money -= reroll_cost;
     display_money(); // Update the money display
 
-    List* shop_jokers_list = &s_shop_jokers_list;
-    ListItr itr = list_itr_create(shop_jokers_list);
-    JokerObject* joker_object;
+    List* shop_items_list = &s_shop_items_list;
+    ListItr itr = list_itr_create(shop_items_list);
+    Item* item;
 
-    while ((joker_object = list_itr_next(&itr)))
+    while ((item = list_itr_next(&itr)))
     {
-        if (joker_object != NULL)
+        if (item != NULL && item->type == ITEM_TYPE_JOKER)
         {
-            game_shop_set_joker_avail(joker_object->joker->id, true);
-            joker_object_destroy(&joker_object); // Destroy the joker object if it exists
+            item_dispose(&item);
         }
     }
 
-    list_clear(shop_jokers_list);
-    *shop_jokers_list = list_init();
+    list_clear(shop_items_list);
+    *shop_items_list = list_init();
 
-    game_shop_create_items();
+    game_shop_create_top_row_items();
 
-    itr = list_itr_create(shop_jokers_list);
+    itr = list_itr_create(shop_items_list);
 
-    while ((joker_object = list_itr_next(&itr)))
+    SpriteObject* item_sprite_object;
+    while ((item_sprite_object = list_itr_next(&itr)))
     {
-        if (joker_object != NULL)
+        if (item_sprite_object != NULL)
         {
-            // Set the y position to the target position
-            joker_object->sprite_object->y = joker_object->sprite_object->ty;
+            item_sprite_object->y = item_sprite_object->ty;
 
-            // Give the joker a little wiggle animation
-            joker_object_shake(joker_object, UNDEFINED);
+            sprite_object_shake(item_sprite_object, UNDEFINED);
         }
     }
 
@@ -672,9 +570,9 @@ static void game_shop_process_user_input(void)
         // Jokers for sale
         case 1:
         {
-            description_card_original_list = &s_shop_jokers_list;
+            description_card_original_list = &s_shop_items_list;
             tmp_card = (shop_selection_grid.selection.x > 0)
-                         ? list_get_at_idx(&s_shop_jokers_list, shop_selection_grid.selection.x - 1)
+                         ? list_get_at_idx(&s_shop_items_list, shop_selection_grid.selection.x - 1)
                          : NULL;
             break;
         }
@@ -692,12 +590,11 @@ static void game_shop_process_user_input(void)
     // Show description of selected card when pressing B.
     // Always wait for the card in question to be immobile to avoid accumulating
     // errors when pressing and releasing B in quick succession.
-    if (tmp_card != NULL && tmp_card->sprite_object->vx == 0 && tmp_card->sprite_object->vy == 0 &&
-        key_held(DESELECT_CARDS))
+    if (tmp_card != NULL && tmp_card->vx == 0 && tmp_card->vy == 0 && key_held(DESELECT_CARDS))
     {
         description_card = tmp_card;
-        description_card_original_x_pos = description_card->sprite_object->x;
-        description_card_original_y_pos = description_card->sprite_object->y;
+        description_card_original_x_pos = description_card->x;
+        description_card_original_y_pos = description_card->y;
 
         timer = TM_ZERO;
         state_machine_change_state(&shop_sm, GAME_SHOP_SHOW_CARD_DESC);
@@ -723,21 +620,21 @@ static void game_shop_show_card_desc(void)
         while ((joker_object = list_itr_next(&itr)))
         {
             if (joker_object != description_card)
-                joker_object->sprite_object->ty -= int2fx(OWNED_CARDS_HIDE_Y_OFFSET);
+                joker_object->ty -= int2fx(OWNED_CARDS_HIDE_Y_OFFSET);
         }
 
         // Shop Jokers
-        itr = list_itr_create(&s_shop_jokers_list);
+        itr = list_itr_create(&s_shop_items_list);
         while ((joker_object = list_itr_next(&itr)))
         {
             if (joker_object != description_card)
-                joker_object->sprite_object->ty = int2fx(SHOP_JOKER_SPRITES_INIT_POS.y + TILE_SIZE);
+                joker_object->ty = int2fx(SHOP_JOKER_SPRITES_INIT_POS.y + TILE_SIZE);
         }
 
         // Set description_card new target position
 
-        description_card->sprite_object->tx = int2fx(CARD_DESCRIPTION_SPRITE_POS.x);
-        description_card->sprite_object->ty = int2fx(CARD_DESCRIPTION_SPRITE_POS.y);
+        description_card->tx = int2fx(CARD_DESCRIPTION_SPRITE_POS.x);
+        description_card->ty = int2fx(CARD_DESCRIPTION_SPRITE_POS.y);
     }
 
     // First 12 anim frames
@@ -795,8 +692,7 @@ static void game_shop_show_card_desc(void)
 
     // Actively wait for the B button to be released, but only if the described card has stopped
     // moving
-    else if (description_card->sprite_object->vx == 0 && description_card->sprite_object->vy == 0 &&
-             !key_held(DESELECT_CARDS))
+    else if (description_card->vx == 0 && description_card->vy == 0 && !key_held(DESELECT_CARDS))
     {
         timer = TM_ZERO;
         state_machine_change_state(&shop_sm, GAME_SHOP_HIDE_CARD_DESC);
@@ -833,19 +729,19 @@ static void game_shop_hide_card_desc(void)
         while ((joker_object = list_itr_next(&itr)))
         {
             if (joker_object != description_card)
-                joker_object->sprite_object->ty = int2fx(HELD_JOKERS_POS.y);
+                joker_object->ty = int2fx(HELD_JOKERS_POS.y);
         }
 
         // Shop Jokers
-        itr = list_itr_create(&s_shop_jokers_list);
+        itr = list_itr_create(&s_shop_items_list);
         while ((joker_object = list_itr_next(&itr)))
         {
             if (joker_object != description_card)
-                joker_object->sprite_object->ty = int2fx(ITEM_SHOP_Y);
+                joker_object->ty = int2fx(ITEM_SHOP_Y);
         }
 
-        description_card->sprite_object->tx = description_card_original_x_pos;
-        description_card->sprite_object->ty = description_card_original_y_pos;
+        description_card->tx = description_card_original_x_pos;
+        description_card->ty = description_card_original_y_pos;
     }
 
     // First 12 anim frames
@@ -862,22 +758,19 @@ static void game_shop_hide_card_desc(void)
     else if (timer == TM_SHOW_CARD_DESC_WAIT + 1)
     {
         // Need to account for the description_card being selected if it came from the shop.
-        if (description_card_original_list == &s_shop_jokers_list)
-            description_card->sprite_object->ty += int2fx(TILE_SIZE);
+        if (description_card_original_list == &s_shop_items_list)
+            description_card->ty += int2fx(TILE_SIZE);
 
         // Print price under shop Jokers
-        JokerObject* joker_object = NULL;
-        ListItr itr = list_itr_create(&s_shop_jokers_list);
-        while ((joker_object = list_itr_next(&itr)))
+        Item* item = NULL;
+        ListItr itr = list_itr_create(&s_shop_items_list);
+        while ((item = list_itr_next(&itr)))
         {
-            sprite_object_print_price_under(
-                joker_object->sprite_object,
-                joker_object->joker->value
-            );
+            item_print_buy_price_under(item);
         }
 
-        if (description_card_original_list == &s_shop_jokers_list)
-            description_card->sprite_object->ty -= int2fx(TILE_SIZE);
+        if (description_card_original_list == &s_shop_items_list)
+            description_card->ty -= int2fx(TILE_SIZE);
 
         // Print Reroll prince
         tte_printf(
@@ -893,7 +786,7 @@ static void game_shop_hide_card_desc(void)
     }
 
     // Cleanup and change state
-    else if (description_card->sprite_object->vx == 0 && description_card->sprite_object->vy == 0)
+    else if (description_card->vx == 0 && description_card->vy == 0)
     {
         owned_joker_price_printed = false;
         description_card = NULL;
@@ -908,7 +801,7 @@ static void game_shop_hide_card_desc(void)
     {
         owned_joker_price_printed = true;
         sprite_object_print_price_under(
-            description_card->sprite_object,
+            (SpriteObject*)description_card,
             joker_get_sell_value(description_card->joker)
         );
     }
@@ -925,19 +818,17 @@ static void game_shop_outro(void)
 
     main_bg_se_copy_rect_1_tile_vert(TOP_LEFT_PANEL_ANIM_RECT, SCREEN_UP);
 
-    // TODO: make heads or tails of what's going on here and replace
-    // magic numbers.
     if (timer == 1)
     {
         tte_erase_rect_wrapper(SHOP_PRICES_TEXT_RECT); // Erase the shop prices text
 
-        ListItr itr = list_itr_create(&s_shop_jokers_list);
-        JokerObject* joker_object;
-        while ((joker_object = list_itr_next(&itr)))
+        ListItr itr = list_itr_create(&s_shop_items_list);
+        SpriteObject* shop_item;
+        while ((shop_item = list_itr_next(&itr)))
         {
-            if (joker_object != NULL)
+            if (shop_item != NULL)
             {
-                joker_object->sprite_object->ty = int2fx(160);
+                shop_item->ty = int2fx(160);
             }
         }
 
@@ -945,6 +836,8 @@ static void game_shop_outro(void)
     }
     else if (timer == 2)
     {
+        // TODO: make heads or tails of what's going on here and replace
+        // magic numbers.
         int y = 5;
         memset16(&se_mat[MAIN_BG_SBB][y - 1][0], 0x0001, 1);
         memset16(&se_mat[MAIN_BG_SBB][y - 1][1], 0x0002, 7);
@@ -998,21 +891,16 @@ void game_shop_on_update(void)
 
 void game_shop_on_exit(void)
 {
-    List* shop_jokers_list = &s_shop_jokers_list;
-    ListItr itr = list_itr_create(shop_jokers_list);
-    JokerObject* joker_object;
+    List* shop_items_list = &s_shop_items_list;
+    ListItr itr = list_itr_create(shop_items_list);
+    Item* item;
 
-    while ((joker_object = list_itr_next(&itr)))
+    while ((item = list_itr_next(&itr)))
     {
-        if (joker_object != NULL)
-        {
-            // Make the joker available back to shop
-            game_shop_set_joker_avail(joker_object->joker->id, true);
-        }
-        joker_object_destroy(&joker_object); // Destroy the joker objects
+        item_dispose(&item);
     }
 
-    list_clear(shop_jokers_list);
+    list_clear(shop_items_list);
 
     increment_blind(BLIND_STATE_DEFEATED); // TODO: Move to game_round_end()?
 

source/hand.c

@@ -258,7 +258,7 @@ void reorder_card_sprites_layers(void)
         }
 
         // card_object_get_sprite() will not work here since we need the address
-        sprite_destroy(&(hand.cards[i]->sprite_object->sprite));
+        sprite_destroy(&(hand.cards[i]->sprite));
     }
 
     // Recreate the sprites for the remaining non NULL cards, in order
@@ -270,8 +270,8 @@ void reorder_card_sprites_layers(void)
             card_object_set_sprite(hand.cards[i], i);
             sprite_position(
                 card_object_get_sprite(hand.cards[i]),
-                fx2int(hand.cards[i]->sprite_object->x),
-                fx2int(hand.cards[i]->sprite_object->y)
+                fx2int(hand.cards[i]->x),
+                fx2int(hand.cards[i]->y)
             );
         }
     }

source/item.c

@@ -0,0 +1,71 @@
+#include "item.h"
+
+#include "item_funcs.h"
+#include "mgba_logger.h"
+#include "util.h"
+
+#include <tonc.h>
+
+Item* item_roll_new(enum ItemType item_type)
+{
+    if ((int)item_type < 0 || item_type >= ITEM_NUM_TYPES)
+    {
+        MGBA_FUNC_ERROR("Undefined type %d", item_type);
+        return NULL;
+    }
+
+    ItemFuncs* item_funcs = get_item_type_funcs(item_type);
+    GBAL_RETURN_IF_NULL_RET(item_funcs, NULL);
+    GBAL_RETURN_IF_NULL_RET(item_funcs->roll_new, NULL);
+
+    return item_funcs->roll_new();
+}
+
+int item_get_buy_price(Item* item)
+{
+    GBAL_RETURN_IF_NULL_RET(item, UNDEFINED);
+
+    ItemFuncs* item_funcs = get_item_type_funcs(item->type);
+    GBAL_RETURN_IF_NULL_RET(item_funcs, UNDEFINED);
+    GBAL_RETURN_IF_NULL_RET(item_funcs->get_buy_price, UNDEFINED);
+
+    return item_funcs->get_buy_price(item);
+}
+
+void item_acquire(Item* item)
+{
+    GBAL_RETURN_IF_NULL_VOID(item);
+
+    ItemFuncs* item_funcs = get_item_type_funcs(item->type);
+    GBAL_RETURN_IF_NULL_VOID(item_funcs);
+    GBAL_RETURN_IF_NULL_VOID(item_funcs->acquire);
+
+    item_funcs->acquire(item);
+}
+
+bool item_can_acquire(Item* item)
+{
+    GBAL_RETURN_IF_NULL_RET(item, false);
+    ItemFuncs* item_funcs = get_item_type_funcs(item->type);
+    GBAL_RETURN_IF_NULL_RET(item_funcs, false);
+    GBAL_RETURN_IF_NULL_RET(item_funcs->can_acquire, false);
+
+    return item_funcs->can_acquire(item);
+}
+
+void item_dispose(Item** item)
+{
+    GBAL_RETURN_IF_NULL_VOID(item);
+    GBAL_RETURN_IF_NULL_VOID(*item);
+    ItemFuncs* item_funcs = get_item_type_funcs((*item)->type);
+    GBAL_RETURN_IF_NULL_VOID(item_funcs);
+    GBAL_RETURN_IF_NULL_VOID(item_funcs->dispose);
+
+    item_funcs->dispose(item);
+}
+
+void item_print_buy_price_under(Item* item)
+{
+    GBAL_RETURN_IF_NULL_VOID(item);
+    sprite_object_print_price_under((SpriteObject*)item, item_get_buy_price(item));
+}

source/item_funcs.c

@@ -0,0 +1,65 @@
+#include "item_funcs.h"
+
+#include "card.h"
+#include "game.h"
+#include "game/shop.h"
+#include "joker.h"
+#include "util.h"
+
+static Item* item_roll_new_unimplemented();
+static void item_acquire_unimplemented(Item* item);
+static bool item_always_can_acquire(Item* item);
+
+// clang-format off
+ItemFuncs item_func_table[] = {
+    [ITEM_TYPE_JOKER] = {
+        .roll_new = joker_object_roll_new,
+        .get_buy_price = joker_object_get_buy_price,
+        .acquire = joker_object_add_to_owned,
+        .can_acquire = joker_object_can_acquire,
+        .dispose = joker_object_dispose
+    },
+    
+    /* Currently playing cards have partial implementations since Magic Trick is not implemented
+     * and playing cards can't appear in the shop.
+     * If the Magic Trick voucher is implemented, these need to be completed.
+     * Playing cards must stay the only exception, the rest of the item types must implement
+     * all the basic functions to appear in the shop.
+     */
+    [ITEM_TYPE_PLAYING_CARD] = {
+        .roll_new = item_roll_new_unimplemented,
+        .get_buy_price = card_object_get_buy_price,
+        .acquire = item_acquire_unimplemented,
+        .can_acquire = item_always_can_acquire,
+        .dispose = card_object_dispose
+    }
+};
+// clang-format on
+
+ItemFuncs* get_item_type_funcs(enum ItemType type)
+{
+    if ((int)type < 0 || type >= NUM_ELEM_IN_ARR(item_func_table))
+    {
+        MGBA_FUNC_ERROR("Invalid type %d", type);
+        return NULL;
+    }
+
+    return &item_func_table[type];
+}
+
+static Item* item_roll_new_unimplemented()
+{
+    MGBA_FUNC_ERROR("Unimplemented roll_new function called");
+    return NULL;
+}
+
+static void item_acquire_unimplemented(Item* item)
+{
+    GBAL_RETURN_IF_NULL_VOID(item);
+    MGBA_FUNC_ERROR("Unimplemented acquire function called for item type type %d", (item)->type);
+}
+
+static bool item_always_can_acquire(Item* item)
+{
+    return true;
+}

source/joker.c

@@ -4,6 +4,8 @@
 #include "game/round.h"
 #include "game_variables.h"
 #include "graphic_utils.h"
+#include "layout.h"
+#include "mgba_logger.h"
 #include "pool.h"
 #include "random.h"
 #include "soundbank.h"
@@ -11,6 +13,7 @@
 
 // Tiles and palettes
 #include "card_rarity_pal_gfx.h"
+#include "item.h"
 #include "joker_gfx.h"
 
 #include <maxmod.h>
@@ -58,6 +61,8 @@ static bool used_layers[MAX_JOKER_OBJECTS] = {false}; // Track used layers for j
 static int joker_spritesheet_pb_map[MAX_NUM_JOKERS_SPRITESHEETS];
 static int joker_pb_num_sprite_users[JOKER_LAST_PB - JOKER_BASE_PB + 1] = {0};
 
+BITSET_DEFINE(s_rollable_jokers_bitset, MAX_DEFINABLE_JOKERS)
+
 // See linked issue for context of maps
 // https://github.com/GBALATRO/balatro-gba/issues/274#issue-3685075538
 
@@ -179,12 +184,16 @@ u16 joker_get_rarity_color(u8 rarity, bool main_color)
     return card_rarity_pal_gfxPal[1 + 2 * rarity + (main_color ? 0 : 1)];
 }
 
+int joker_get_buy_price(const Joker* joker)
+{
+    GBAL_RETURN_IF_NULL_RET(joker, UNDEFINED);
+
+    return joker->value;
+}
+
 int joker_get_sell_value(const Joker* joker)
 {
-    if (joker == NULL)
-    {
-        return UNDEFINED;
-    }
+    GBAL_RETURN_IF_NULL_RET(joker, UNDEFINED);
 
     return joker->value / 2;
 }
@@ -194,6 +203,8 @@ JokerObject* joker_object_new(Joker* joker)
 {
     JokerObject* joker_object = POOL_GET(JokerObject);
 
+    sprite_object_init((SpriteObject*)joker_object);
+
     int layer = 0;
     for (int i = 0; i < MAX_JOKER_OBJECTS; i++)
     {
@@ -206,7 +217,8 @@ JokerObject* joker_object_new(Joker* joker)
     }
 
     joker_object->joker = joker;
-    joker_object->sprite_object = sprite_object_new();
+
+    joker_object->type = ITEM_TYPE_JOKER;
 
     int tile_index = JOKER_TID + layer * JOKER_SPRITE_OFFSET;
 
@@ -222,7 +234,7 @@ JokerObject* joker_object_new(Joker* joker)
     );
 
     sprite_object_set_sprite(
-        joker_object->sprite_object,
+        (SpriteObject*)joker_object,
         sprite_new(
             ATTR0_SQUARE | ATTR0_4BPP | ATTR0_AFF,
             ATTR1_SIZE_32,
@@ -250,18 +262,162 @@ void joker_object_destroy(JokerObject** joker_object)
             UNDEFINED;
     }
 
-    sprite_object_destroy(&(*joker_object)->sprite_object); // Destroy the sprite
-    joker_destroy(&(*joker_object)->joker);                 // Destroy the joker
+    sprite_object_destroy((SpriteObject*)(*joker_object));
+    joker_destroy(&(*joker_object)->joker);
     POOL_FREE(JokerObject, *joker_object);
     *joker_object = NULL;
 }
 
-void joker_object_shake(JokerObject* joker_object, mm_word sound_id)
+void joker_object_dispose(Item** joker_object_item)
 {
-    sprite_object_shake(joker_object->sprite_object, sound_id);
+    GBAL_RETURN_IF_NULL_VOID(joker_object_item);
+    GBAL_RETURN_IF_NULL_VOID(*joker_object_item);
+    ITEM_RETURN_IF_UNEXPECTED_TYPE_VOID(*joker_object_item, ITEM_TYPE_JOKER);
+
+    JokerObject* joker_object = (JokerObject*)(*joker_object_item);
+    GBAL_RETURN_IF_NULL_VOID(joker_object->joker);
+
+    joker_set_rollable(joker_object->joker->id, true);
+
+    joker_object_destroy(&joker_object);
+    *joker_object_item = NULL;
 }
 
-void set_and_shift_text(char* str, int* cursor_pos_x, int* cursor_pos_y, int color_pb)
+void joker_object_shake(JokerObject* joker_object, mm_word sound_id)
+{
+    sprite_object_shake((SpriteObject*)joker_object, sound_id);
+}
+
+int joker_object_get_buy_price(Item* joker_object)
+{
+    GBAL_RETURN_IF_NULL_RET(joker_object, UNDEFINED);
+    ITEM_RETURN_IF_UNEXPECTED_TYPE_RET(joker_object, ITEM_TYPE_JOKER, UNDEFINED);
+
+    return ((JokerObject*)joker_object)->joker->value;
+}
+
+void joker_object_add_to_owned(Item* joker_object)
+{
+    GBAL_RETURN_IF_NULL_VOID(joker_object);
+    ITEM_RETURN_IF_UNEXPECTED_TYPE_VOID(joker_object, ITEM_TYPE_JOKER);
+
+    joker_object->ty = int2fx(HELD_JOKERS_POS.y);
+    add_joker((JokerObject*)joker_object);
+}
+
+void joker_set_rollable(int joker_id, bool rollable)
+{
+    bitset_set_idx(&s_rollable_jokers_bitset, joker_id, rollable);
+}
+
+/**
+ * @brief Computes the number of Jokers we can currently roll in the Shop.
+ *         The Jokers we own is taken into account and can't be rolled again.
+ */
+static inline int get_num_rollable_jokers(void)
+{
+    return bitset_num_set_bits(&s_rollable_jokers_bitset);
+}
+
+/**
+ * @brief Returns true if we can't roll any Joker
+ */
+static inline bool no_rollable_jokers(void)
+{
+    return bitset_is_empty(&s_rollable_jokers_bitset);
+}
+
+GBAL_UNUSED
+static inline bool joker_is_rollable(int joker_id)
+{
+    return bitset_get_idx(&s_rollable_jokers_bitset, joker_id);
+}
+
+void joker_reset_rollable_jokers(void)
+{
+    int num_jokers = get_joker_registry_size();
+
+    bitset_clear(&s_rollable_jokers_bitset);
+    for (int i = 0; i < num_jokers; i++)
+    {
+        bitset_set_idx(&s_rollable_jokers_bitset, i, true);
+    }
+}
+
+/**
+ * @brief Rolls a random Joker among the available ones
+ */
+static int joker_roll_id(void)
+{
+    // Now determine how many jokers are available based on the rarity
+    int jokers_avail_size = get_num_rollable_jokers();
+
+    if (jokers_avail_size == 0)
+        return UNDEFINED;
+
+    // Roll for what rarity the joker will be
+    int joker_rarity = joker_get_random_rarity();
+
+    int matching_joker_ids[jokers_avail_size];
+    int fallback_random_idx = rng_get_u32() % jokers_avail_size;
+    int fallback_random_joker_id = UNDEFINED;
+    int match_count = 0;
+
+    BitsetItr itr = bitset_itr_create(&s_rollable_jokers_bitset);
+
+    int i = 0;
+    int joker_id = UNDEFINED;
+    while ((joker_id = bitset_itr_next(&itr)) != UNDEFINED)
+    {
+        if (i++ == fallback_random_idx)
+            fallback_random_joker_id = joker_id;
+        const JokerInfo* info = get_joker_registry_entry(joker_id);
+        if (info->rarity == joker_rarity)
+        {
+            matching_joker_ids[match_count++] = joker_id;
+        }
+    }
+
+    int selected_joker_id = (match_count > 0) ? matching_joker_ids[rng_get_u32() % match_count]
+                                              : fallback_random_joker_id;
+
+    return selected_joker_id;
+}
+
+Item* joker_object_roll_new(void)
+{
+    if (no_rollable_jokers())
+        return NULL;
+
+    int joker_id = 0;
+#ifdef TEST_JOKER_ID0 // Allow defining an ID for a joker to always appear in shop and be tested
+    if (joker_is_rollable(TEST_JOKER_ID0))
+    {
+        joker_id = TEST_JOKER_ID0;
+    }
+    else
+#endif
+#ifdef TEST_JOKER_ID1
+        if (joker_is_rollable(TEST_JOKER_ID1))
+    {
+        joker_id = TEST_JOKER_ID1;
+    }
+    else
+#endif
+    {
+        joker_id = joker_roll_id();
+    }
+
+    // If for some reason only no joker is left, don't make another
+    if (joker_id == UNDEFINED)
+        return NULL;
+
+    joker_set_rollable(joker_id, false);
+
+    return (Item*)joker_object_new(joker_new(joker_id));
+}
+
+static void set_and_shift_text(char* str, int* cursor_pos_x, int* cursor_pos_y, int color_pb)
 {
     tte_set_pos(*cursor_pos_x, *cursor_pos_y);
     tte_set_special(color_pb * TTE_SPECIAL_PB_MULT_OFFSET);
@@ -305,12 +461,12 @@ bool joker_object_score(
     {
         // display the text on top of the card instead of below the Joker for Held Cards effects
         // scored_card cannot be NULL here because of the joker event
-        cursorPosX += fx2int(card_object->sprite_object->x);
+        cursorPosX += fx2int(card_object->x);
         cursorPosY = HELD_CARD_SCORE_TEXT_Y;
     }
     else
     {
-        cursorPosX += fx2int(joker_object->sprite_object->x);
+        cursorPosX += fx2int(joker_object->x);
         cursorPosY = JOKER_SCORE_TEXT_Y;
     }
 
@@ -375,7 +531,7 @@ Sprite* joker_object_get_sprite(JokerObject* joker_object)
 {
     if (joker_object == NULL)
         return NULL;
-    return sprite_object_get_sprite(joker_object->sprite_object);
+    return sprite_object_get_sprite((SpriteObject*)joker_object);
 }
 
 int joker_get_random_rarity()

source/sprite.c

@@ -4,6 +4,8 @@
 #include "game.h"
 #include "game_variables.h"
 #include "graphic_utils.h"
+#include "item.h"
+#include "mgba_logger.h"
 #include "pool.h"
 #include "random.h"
 #include "soundbank.h"
@@ -169,28 +171,25 @@ int sprite_get_pb(const Sprite* sprite)
 }
 
 // SpriteObject methods
-SpriteObject* sprite_object_new()
+void sprite_object_init(SpriteObject* sprite_object)
 {
-    SpriteObject* sprite_object = POOL_GET(SpriteObject);
+    GBAL_RETURN_IF_NULL_VOID(sprite_object);
+
     sprite_object->sprite = NULL;
     sprite_object_reset_transform(sprite_object);
     sprite_object->focused = false;
 
     list_push_back(&sprite_objects_list, sprite_object);
-
-    return sprite_object;
 }
 
-void sprite_object_destroy(SpriteObject** sprite_object)
+void sprite_object_destroy(SpriteObject* sprite_object)
 {
-    if (*sprite_object == NULL)
+    if (sprite_object == NULL)
         return;
 
-    list_remove_data(&sprite_objects_list, *sprite_object);
+    list_remove_data(&sprite_objects_list, sprite_object);
 
-    sprite_destroy(&(*sprite_object)->sprite);
-    POOL_FREE(SpriteObject, *sprite_object);
-    *sprite_object = NULL;
+    sprite_destroy(&sprite_object->sprite);
 }
 
 void sprite_object_set_sprite(SpriteObject* sprite_object, Sprite* sprite)