Nature Changer NPC

assembly/event_scripts.s

@@ -23,6 +23,7 @@
 .include "assembly/events/elevator_fixing.inc"
 .include "assembly/events/field_moves.inc"
 .include "assembly/events/movement_repl.inc"
+.include "assembly/events/nature_changer.inc"
 .include "assembly/events/registered_item.inc"
 .include "assembly/events/repel_script.inc"
 .include "assembly/events/roclobster.inc"

assembly/events/nature_changer.inc

@@ -0,0 +1,89 @@
+.global EventScript_NatureChanger
+
+EventScript_NatureChanger:
+    lock
+    faceplayer
+    msgbox Text_Intro, MSGBOX_YESNO
+    compare VAR_RESULT, 0
+    goto_if_eq EventScript_NatureChangerCancel
+    call EventScript_NatureChanger_ChoosePokemon
+
+    compare VAR_0x8004, 255
+    goto_if_eq EventScript_NatureChangerCancel
+
+    call EventScript_NatureChanger_CheckIfEgg
+
+    bufferpartymonnick 1, VAR_0x8004
+
+EventScript_NatureChanger_SelectNature:
+    message Text_WhichNature
+    waitmessage
+
+    call EventScript_NatureChanger_ShowNatureWindow
+    closemessage
+
+    @ B Button check
+    compare VAR_RESULT, 127
+    goto_if_eq EventScript_NatureChangerCancel
+
+    @ Cancel option check
+    compare VAR_RESULT, 25
+    goto_if_eq EventScript_NatureChangerCancel
+
+    callnative BufferNatureName
+
+    copyvar VAR_0x8005, VAR_RESULT
+    msgbox Text_AreYouSure, MSGBOX_YESNO
+    compare VAR_RESULT, 0
+    goto_if_eq EventScript_NatureChanger_SelectNature
+
+    callnative ChangePartyMonNature
+    release
+
+    msgbox Text_Changed, MSGBOX_NPC
+    end
+
+EventScript_NatureChangerCancel:
+    msgbox Text_Canceled, MSGBOX_NPC
+    releaseall
+    end
+
+EventScript_NatureChangerIsEgg:
+    msgbox Text_IsEgg, MSGBOX_NPC
+    releaseall
+    end
+
+EventScript_NatureChanger_ChoosePokemon:
+    callnative (0x80f9a0c | 1)
+    waitstate
+    return
+
+EventScript_NatureChanger_CheckIfEgg:
+    specialvar_ VAR_RESULT, 0x147
+    compare VAR_RESULT, SPECIES_EGG
+
+    goto_if_eq EventScript_NatureChangerIsEgg
+    return
+
+EventScript_NatureChanger_ShowNatureWindow:
+    callnative DrawNaturesWindow
+    waitstate
+    return
+
+Text_Intro:
+    .string "Would you like me to change one of your\nPOKéMON's NATURE?$"
+
+Text_WhichNature:
+    .string "Which nature should I give\n{STR_VAR_2}?$"
+
+Text_Canceled:
+    .string "Come visit me if you have a change of\nheart.$"
+
+Text_IsEgg:
+    .string "I can't change the NATURE of an EGG!$"
+
+Text_AreYouSure:
+    .string "Are you sure you want to change\n{STR_VAR_2}'s NATURE to {STR_VAR_1}?$"
+
+Text_Changed:
+    .string "I've changed your {STR_VAR_2}'s NATURE\nto {STR_VAR_1}!$"

assembly/macros/events.inc

@@ -267,6 +267,12 @@
 	.2byte SPECIAL_\function
 	.endm
 
+	.macro specialvar_ output:req, function:req
+	.byte 0x26
+	.2byte \output
+	.2byte \function
+	.endm
+
 	@ Blocks script execution until a command or ASM code manually unblocks it. Generally used with specific commands and specials. If this command runs, and a subsequent command or piece of ASM does not unblock state, the script will remain blocked indefinitely (essentially a hang).
 	.macro waitstate
 	.byte 0x27

config.asm

@@ -72,6 +72,9 @@
 ; New Game speech uses the dialogue box instead of the normal menu box.
 .definelabel BIRCH_SPEECH_DBOX, 1
 
+; Adds a Nature Changer NPC to Verdanturf's Endless Plains.
+.definelabel NATURE_CHANGER, 1
+
 ; Bugfixes
 ; --------
 

include/menu.h

@@ -19,3 +19,7 @@ void LONG_CALL Menu_EraseWindowRect(u8, u8, u8, u8);
 void LONG_CALL Menu_BlankWindowRect(u8 left, u8 top, u8 right, u8 bottom);
 u8 LONG_CALL PrintStringWithNewlines(
     void *win, u8 *dest, const u8 *src, u16 tileDataStartOffset, u8 left, u16 top, u8 width, u32 a8);
+void LONG_CALL Menu_PrintItems(u8, u8, u8, const void *);
+void LONG_CALL Menu_DestroyCursor(void);
+u8 LONG_CALL InitMenu(u8, u8, u8, u8, u8, u8);
+u8 LONG_CALL Menu_MoveCursor(s8);

include/palette.h

@@ -8,3 +8,25 @@ bool8 LONG_CALL BeginNormalPaletteFade(u32 selectedPalettes, s8 delay, u8 startY
 void LONG_CALL LoadPalette(const void *, u16, u16);
 void LONG_CALL LoadCompressedPalette(const void *, u16, u16);
 void LONG_CALL TransferPlttBuffer(void);
+
+struct PaletteFadeControl
+{
+    /*0x00*/    u32 multipurpose1;
+    /*0x04*/    u8 delayCounter:6;
+    /*0x05*/    u16 y:5; // blend coefficient
+    /*0x05-06*/ u16 targetY:5; // target blend coefficient
+    /*0x07*/    u16 blendColor:15;
+    /*0x07*/    u16 active:1;
+    /*0x08*/    u16 multipurpose2:6;
+    /*0x08*/    u16 yDec:1; // whether blend coefficient is decreasing
+    /*0x08*/    u16 bufferTransferDisabled:1;
+    /*0x09*/    u16 mode:2;
+    /*0x09*/    u16 shouldResetBlendRegisters:1;
+    /*0x09*/    u16 hardwareFadeFinishing:1;
+    /*0x09-0a*/ u16 softwareFadeFinishingCounter:5;
+    /*0x0a*/    u16 softwareFadeFinishing:1;
+    /*0x0a*/    u16 objPaletteToggle:1;
+    /*0x0a*/    u8 deltaY:4; // rate of change of blend coefficient
+};
+
+extern struct PaletteFadeControl gPaletteFade;

include/pokemon.h

@@ -35,9 +35,38 @@ struct ContestMove
     u8 comboMoves[4];
 };
 
+struct PACKED BoxPokemon
+{
+    u32 personality;
+    u32 otId;
+    u8 nickname[POKEMON_NAME_LENGTH];
+    u8 language;
+    u8 isBadEgg:1;
+    u8 hasSpecies:1;
+    u8 isEgg:1;
+    u8 blockBoxRS:1; // Unused, but Pokémon Box Ruby & Sapphire will refuse to deposit a Pokémon with this flag set
+    u8 otName[7];
+    u8 markings;
+    u16 checksum;
+    u16 nature:5;
+    u16 unk0:11;
+
+    u8 unk1[80 - 32];
+};
+
 struct PACKED Pokemon
 {
-    u8 unk0[100];
+    /*0x00*/ struct BoxPokemon box;
+    /*0x50*/ u32 status;
+    /*0x54*/ u8 level;
+    /*0x55*/ u8 mail;
+    /*0x56*/ u16 hp;
+    /*0x58*/ u16 maxHP;
+    /*0x5A*/ u16 attack;
+    /*0x5C*/ u16 defense;
+    /*0x5E*/ u16 speed;
+    /*0x60*/ u16 spAttack;
+    /*0x62*/ u16 spDefense;
 };
 
 #define BATTLE_STATS_NO 8
@@ -87,12 +116,19 @@ extern const struct BattleMove gBattleMoves[];
 u32 LONG_CALL CanMonLearnTMHM(struct Pokemon *mon, u8 tm);
 bool8 LONG_CALL MonKnowsMove(struct Pokemon *mon, u16 move);
 u32 LONG_CALL GetMonData(struct Pokemon *mon, s32 field);
+void LONG_CALL SetMonData(struct Pokemon *mon, s32 field, u32 dataArg);
 u8 LONG_CALL CountAliveMons(u8 a1);
 bool8 CheckIfMonCanUseHM(struct Pokemon *mon, u16 hm);
 bool8 LONG_CALL CheckIfPartyCanUseTM(u16 tm);
 u8 LONG_CALL CalculatePPWithBonus(u16 move, u8 ppBonuses, u8 moveIndex);
 bool8 LONG_CALL IsHMMove(u16 move);
 u8 LONG_CALL GetNature(struct Pokemon *mon);
+u8 LONG_CALL GetNatureFromPersonality(u32 personality);
+u16 LONG_CALL CalculateBoxMonChecksum(struct BoxPokemon *boxMon);
+void LONG_CALL EncryptBoxMon(struct BoxPokemon *boxMon);
+void LONG_CALL DecryptBoxMon(struct BoxPokemon *boxMon);
+void LONG_CALL SetBoxMonData(struct BoxPokemon *boxMon, s32 field, u32 dataArg);
+void LONG_CALL CalculateMonStats(struct Pokemon *mon);
 
 enum
 {
@@ -106,4 +142,5 @@ enum
     STAT_STAGE_EVASION, // 7
 };
 
-extern const s8 gNatureStatTable[25][5];
+extern const s8 gNatureStatTable[25][5];
+extern const u8 *const gNatureNames[25];

include/random.h

@@ -0,0 +1,4 @@
+#pragma once
+
+u16 LONG_CALL Random16(void);
+#define Random32() (Random16() << 16 | Random16())

include/script.h

@@ -24,3 +24,4 @@ void LONG_CALL ScriptContext1_SetupScript(const u8 *ptr);
 void LONG_CALL ScriptContext2_Enable(void);
 void LONG_CALL ScriptContext1_Stop(void);
 bool8 LONG_CALL ScriptContext2_IsEnabled(void);
+void LONG_CALL EnableBothScriptContexts(void);

include/script_menu.h

@@ -9,9 +9,11 @@ struct MenuAction
 };
 
 extern u16 gSpecialVar_0x8004;
+extern u16 gSpecialVar_0x8005;
 extern u16 gSpecialVar_Result;
 extern u8 gRepelMenuChoices[3];
 
 void LONG_CALL DrawMultichoiceMenu(
     u8 left, u8 top, u8 count, const struct MenuAction *list, u8 ignoreBPress, u8 cursorPos);
 u8 LONG_CALL CreateTrainerSprite(u8 trainerSpriteID, s16 x, s16 y, u8 subpriority, u8 *buffer);
+void DrawListMenu(u8 left, u8 top, u8 displayCount, u8 totalCount, const struct MenuAction *list, u8 ignoreBPress, u8 cursorPos);

linker.ld

@@ -23,6 +23,11 @@ SECTIONS {
     ALIGN(4)
     {
         *(.rodata);
+    } > rom = 0xff
+
+    .script_data :
+    ALIGN(4)
+    {
         *(.script_data);
     } > rom = 0xff
 

linker/ram.ld

@@ -46,12 +46,14 @@ gMapHeader = 0x202e828;
 gPlayerAvatar = 0x202e858;
 gFieldMessageBoxWindow = 0x0202e87c;
 gSpecialVar_0x8004 = 0x202e8cc;
+gSpecialVar_0x8005 = 0x202e8ce;
 gSpecialVar_Result = 0x202e8dc;
 gPartyMenuUseExitCallback = 0x202e8f4;
 gMenuWindowPtr = 0x202e9c8;
 gMenuTextTileOffset = 0x202e9ce;
 gPlttBufferUnfaded = 0x202eac8;
 gPlttBufferFaded = 0x202eec8;
+gPaletteFade = 0x202f388;
 gTrainerBattleOpponent = 0x202ff5e;
 gFieldEffectArguments = 0x202ff84;
 sPokeMenuCursorPos = 0x202ffa8;

linker/rodata.ld

@@ -45,3 +45,4 @@ gOtherText_Pokedex = 0x842c992;
 gOtherText_PlayTime = 0x842c99a;
 
 gStatStageRatios = 0x8208244;
+gNatureNames = 0x83c1004;

linker/text.ld

@@ -33,6 +33,7 @@ SetMonSpriteTemplate = 0x803c56c | 1;
 GetMonData = 0x803cb60 | 1;
 CalculatePPWithBonus = 0x803ddec | 1;
 GetNature = 0x803f464 | 1;
+GetNatureFromPersonality = 0x803f47c | 1;
 CanMonLearnTMHM = 0x8040374 | 1;
 InitMapView = 0x8053220 | 1;
 LoadMapTilesetPalettes = 0x8056d84 | 1;
@@ -217,3 +218,16 @@ UpdateShadowFieldEffect = 0x8126d10 | 1;
 SetSurfBlob_BobState = 0x8127ed0 | 1;
 CB2_ShowDiploma = 0x8145d88 | 1;
 LoadCompressedObjectPic = 0x800d250 | 1;
+GetStringWidthInTilesForScriptMenu = 0x80b511d | 1;
+Menu_PrintItems = 0x80728a0 | 1;
+Menu_DestroyCursor = 0x8072dec | 1;
+InitMenu = 0x8072d40 | 1;
+EnableBothScriptContexts = 0x80655fc | 1;
+Menu_MoveCursor = 0x80720c4 | 1;
+Random16 = 0x8040e84 | 1;
+SetMonData = 0x803d1fc | 1;
+SetBoxMonData = 0x803d2ec | 1;
+CalculateBoxMonChecksum = 0x803b124 | 1;
+EncryptBoxMon = 0x803c5f0 | 1;
+DecryptBoxMon = 0x803c614 | 1;
+CalculateMonStats = 0x803b1b8 | 1;

main.asm

@@ -60,6 +60,7 @@
 .include "scripts/exp_on_capture.asm"
 .include "scripts/hm_system.asm"
 .include "scripts/more_exp.asm"
+.include "scripts/nature_changer.asm"
 .include "scripts/new_title_screen.asm"
 .include "scripts/ow_shadows.asm"
 .include "scripts/ps_split.asm"

scripts/nature_changer.asm

@@ -0,0 +1,12 @@
+.if NATURE_CHANGER
+
+.org 0x86C9A10
+.word EventScript_NatureChanger
+
+.org 0x803f464
+set_function_hook r1, GetNature_
+
+
+set_nop_bl 0x811233a
+
+.endif

src/field_message_box.c

@@ -74,3 +74,8 @@ void HideFieldMessageBoxInstant(void)
     TextWindow_EraseDialogueFrame(&gFieldMessageBoxWindow);
     sMessageBoxMode = FIELD_MESSAGE_BOX_HIDDEN;
 }
+
+void ShowFieldMessageInstantBuffer(void)
+{
+    ShowFieldMessageInstant(gStringVar1);
+}

src/pokemon.c

@@ -88,3 +88,9 @@ void CheckIfPartyHasMoveForElevator(void)
         }
     }
 }
+
+u8 GetNature_(struct Pokemon *mon)
+{
+    if (mon->box.nature == 0) return GetNatureFromPersonality(GetMonData(mon, MON_DATA_PERSONALITY));
+    return mon->box.nature - 1;
+}