ref: f305b27025562df97aa35e0f535a0b6892f4f101
dir: /extras/README.md/
Pokémon Crystal utilities and extras ============================== `crystal.py` parses the ROM into classes and objects. It prmarily parses map headers, "second" map headers, map event headers, map script headers, map triggers, map "callbacks", map blockdata, xy triggers, warps, people-events, texts and scripts. The purpose of the file is to parse the ROM into python and then spit it back out with the global `to_asm()` method. #### Simple ASM generation example Note: throughout these examples it is possible to use `reload(crystal)` instead of `import crystal`. Once the module is loaded a first time, it must be reloaded if the file changes and the updates are desired. ```python import crystal # parse the ROM crystal.run_main() # create a new dump asm = crystal.Asm() # insert the first 10 maps x = 10 asm.insert_with_dependencies(crystal.all_map_headers[:x]) # dump to extras/output.txt asm.dump() ``` After running those lines, `cp extras/output.txt main.asm` and run `git diff main.asm` to confirm that changes to `main.asm` have occurred. To test whether or not the newly inserted ASM compiles into the same ROM, use: `make clean && make`. This will complain very loudly if something is broken. #### Testing Unit tests cover most of the classes. ```python import crystal crystal.run_tests() ``` #### Parsing a script at a known address Here is a demo of how to investigate a particular script, starting with only an address to a known script (0x58043). In this case, the script calls the `2writetext` command to show some dialog. This dialog will be shown at the end of the example. ```python import crystal # parse the script at 0x58043 from the map event header at 0x584c3 # from the second map header at 0x958b8 # from the map header at 0x941ae # for "Ruins of Alph Outside" (map_group=3 map_id=0x16) script = Script(0x58043) # show the script print script.to_asm() # what labels does it point to in the to_asm output? # these must be present in the final asm file for rgbasm to compile the file objdeps = script.get_dependencies() print str(objdeps) # the individual commands that make up the script commands = script.commands print str(commands) # the 3rd command is 2writetext and points to a text thirdcommand = script.commands[2] print thirdcommand # <crystal.2writetextCommand instance at 0x8ad4c0c> # look at the command parameters params = thirdcommand.params print params # {0: <crystal.RawTextPointerLabelParam instance at 0x8ad4b0c>} # 2writetext always has a single parameter definition_param_count = len(getattr(crystal, "2writetextCommand").param_types.keys()) current_param_count = len(params.keys()) assert definition_param_count == current_param_count, "this should never " + \ "happen: instance of a command has more parameters than the " + \ "definition of the command allows" # get the first parameter (the text pointer) param = params[0] print param # <crystal.RawTextPointerLabelParam instance at 0x8ad4b0c> # RawTextPointerLabelParam instances point to their text text = param.text print text # <crystal.TextScript instance at 0x8ad47ec> # now investigate this text appearing in this script in "Ruins of Alph Outside" print text.to_asm() ``` The final output will be the following text. ```asm db $0, "Hm? That's a #-", $4f db "DEX, isn't it?", $55 ; ... ``` However, this is not how that `TextScript` object would appear in the final ASM. To see how it would appear in `main.asm` once inserted, you would run `print crystal.to_asm(text)` to get the following. ```asm UnknownText_0x580c7: ; 0x580c7 db $0, "Hm? That's a #-", $4f db "DEX, isn't it?", $55 db "May I see it?", $51 db "There are so many", $4f db "kinds of #MON.", $51 db "Hm? What's this?", $51 db "What is this", $4f db "#MON?", $51 db "It looks like the", $4f db "strange writing on", $51 db "the walls of the", $4f db "RUINS.", $51 db "If those drawings", $4f db "are really #-", $55 db "MON, there should", $55 db "be many more.", $51 db "I know! Let me up-", $4f db "grade your #-", $55 db "DEX. Follow me.", $57 ; 0x581e5 ``` #### Figuring out where a script appears based on a known address Another approach is to parse the entire ROM, then check a script at a particular address. This has the advantage that the script object will have the `map_group` and `map_id` variables set. ```python import crystal # parse the ROM crystal.run_main() # get the parsed script script = crystal.script_parse_table[0x58043] # read its attributes to figure out map group / map id map_group = script.map_group map_id = script.map_id # MapHeader is not given all the info yet # in the mean time "map_names" contains some metadata map_dict = crystal.map_names[map_group][map_id] map_header = map_dict["header_new"] print map_dict["name"] # Ruins of Alph Outside ``` While the above doesn't show this, it turns out that the script at 0x58043 is referenced in the `MapEventHeader` as a person-event. ```python print map_header.second_map_header.event_header.to_asm() ``` This will show a structure roughly like: ```asm person_event $3c, 19, 15, $7, $0, 255, 255, $0, 0, UnknownScript_0x58043, $0703 ``` within this: ```asm MapEventHeader_0x584c3: ; 0x584c3 ; filler db 0, 0 ; warps db 11 warp_def $11, $2, 1, GROUP_RUINS_OF_ALPH_HO_OH_CHAMBER, MAP_RUINS_OF_ALPH_HO_OH_CHAMBER warp_def $7, $e, 1, GROUP_RUINS_OF_ALPH_KABUTO_CHAMBER, MAP_RUINS_OF_ALPH_KABUTO_CHAMBER warp_def $1d, $2, 1, GROUP_RUINS_OF_ALPH_OMANYTE_CHAMBER, MAP_RUINS_OF_ALPH_OMANYTE_CHAMBER warp_def $21, $10, 1, GROUP_RUINS_OF_ALPH_AERODACTYL_CHAMBER, MAP_RUINS_OF_ALPH_AERODACTYL_CHAMBER warp_def $d, $a, 1, GROUP_RUINS_OF_ALPH_INNER_CHAMBER, MAP_RUINS_OF_ALPH_INNER_CHAMBER warp_def $b, $11, 1, GROUP_RUINS_OF_ALPH_RESEARCH_CENTER, MAP_RUINS_OF_ALPH_RESEARCH_CENTER warp_def $13, $6, 1, GROUP_UNION_CAVE_B1F, MAP_UNION_CAVE_B1F warp_def $1b, $6, 2, GROUP_UNION_CAVE_B1F, MAP_UNION_CAVE_B1F warp_def $5, $7, 3, GROUP_ROUTE_36_RUINS_OF_ALPH_GATE, MAP_ROUTE_36_RUINS_OF_ALPH_GATE warp_def $14, $d, 1, GROUP_ROUTE_32_RUINS_OF_ALPH_GATE, MAP_ROUTE_32_RUINS_OF_ALPH_GATE warp_def $15, $d, 2, GROUP_ROUTE_32_RUINS_OF_ALPH_GATE, MAP_ROUTE_32_RUINS_OF_ALPH_GATE ; xy triggers db 2 xy_trigger 1, $e, $b, $0, UnknownScript_0x58031, $0, $0 xy_trigger 1, $f, $a, $0, UnknownScript_0x5803a, $0, $0 ; signposts db 3 signpost 8, 16, $0, UnknownScript_0x580b1 signpost 16, 12, $0, UnknownScript_0x580b4 signpost 12, 18, $0, UnknownScript_0x580b7 ; people-events db 5 person_event $27, 24, 8, $6, $0, 255, 255, $2, 1, Trainer_0x58089, $ffff person_event $3c, 19, 15, $7, $0, 255, 255, $0, 0, UnknownScript_0x58043, $0703 person_event $3a, 21, 17, $3, $0, 255, 255, $a0, 0, UnknownScript_0x58061, $078e person_event $27, 15, 18, $2, $11, 255, 255, $b0, 0, UnknownScript_0x58076, $078f person_event $27, 12, 16, $7, $0, 255, 255, $80, 0, UnknownScript_0x5807e, $078f ; 0x58560 ``` #### Helpful ROM investigation tools ```python import crystal # load the bytes crystal.load_rom() # get a sequence of bytes crystal.rom_interval(0x112116, 10) # ['0x48', '0x54', '0x54', '0x50', '0x2f', '0x31', '0x2e', '0x30', '0xd', '0xa'] crystal.rom_interval(0x112116, 10, strings=False) # [72, 84, 84, 80, 47, 49, 46, 48, 13, 10] # get bytes until a certain byte crystal.rom_until(0x112116, 0x50, strings=False) # ['0x48', '0x54', '0x54'] # [72, 84, 84] # or just look at the encoded characters directly crystal.rom[0x112116:0x112116+10] # 'HTTP/1.0\r\n' # look at a text at 0x197186 text = crystal.parse_text_at2(0x197186, 601, debug=False) print text ``` That last text at 0x197186 will look like: ```python """ OAK: Aha! So you're ! I'm OAK! A #MON researcher. I was just visit- ing my old friend MR.#MON. I heard you were running an errand for PROF.ELM, so I waited here. Oh! What's this? A rare #MON! ... """ ```