Add a new scene script - nickjwilde/pokecrystal GitHub Wiki

This tutorial is for adding a scene event to a map. We'll be Using Azalea Gym as an example.

Define SceneID in WRAM
Define scene_var
Define the Scene
Add the Scene to Azalea Gym

1. Define SceneID in WRAM

Azalea Town Doesn't have a SceneID yet, so we need to define it. Edit wram.asm:

INCLUDE "constants.asm"

INCLUDE "macros/wram.asm"
...
wMobileTradeRoomSceneID::                         db ; d9bf
wMobileBattleRoomSceneID::                        db ; d9c0
+wAzaleaGymSceneID::                              db ; d9c1

-	ds 49
+       ds 48

If you add more Scene Ids in the future you'll have to decrement the number after ds accordingly

2. Define scene_var

Edit data/maps/scenes.asm:

scene_var: MACRO
; map, variable
...
	scene_var MOBILE_BATTLE_ROOM,                          wMobileBattleRoomSceneID
+	scene_var AZALEA_GYM,                                  wAzaleaGymSceneID
	db -1 ; end

3. Define the scene

Edit constants/scene_constants.asm:

; See data/maps/scenes.asm for which maps have scene variables.
; Each scene_script and coord_event is associated with a current scene ID.
...
; wFastShip1FSceneID
	const_def 1
	const SCENE_FASTSHIP1F_ENTER_SHIP   ; 1
	const SCENE_FASTSHIP1F_MEET_GRANDPA ; 2

+; wAzaleaGymSceneID
+	const_def 
+	const SCENE_AZALEAGYM_NOTHING
+	const SCENE_AZALEAGYM_SCENE

4. Add the Scene to Azalea Gym

Edit maps/AzaleaGym.asm:

	object_const_def ; object_event constants
	const AZALEAGYM_BUGSY
...
AzaleaGym_MapScripts:
	def_scene_scripts
+	scene_script .DummyScene0 ; SCENE_AZALEAGYM_NOTHING
+	scene_script .DummyScene1 ; SCENE_AZALEAGYM_SCENE

	def_callbacks

+.DummyScene0
+.DummyScene1
+       end

(Before August 2020, maps did not have def_* macros, so they had to manually declare their quantities of scene_scripts, callbacks, etc. So instead of def_scene_scripts they used to have db 0 ; scene scripts, which you would change here to db 2.)