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Script directory: Difference between revisions

Script directory (view source)

Revision as of 07:56, 7 August 2024

2,111 bytes added ,  7 August
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(Created page with "The script directory (contained in the master file table) contains both bytecode scripts and strings used in the game. It's layout is different than the other directories in the MFT: <syntaxhighlight lang="c"> struct script_directory { u32 unknown; // 0x3ea8eae6 in Boktai 1 (U) script_entry script_entries[]; directory_offsets offsets; // string_index contains the start index (in string_data) for each string // NOTE: offsets.string_i...")
 
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   // string_index contains the start index (in string_data) for each string
   // string_index contains the start index (in string_data) for each string
   // NOTE: offsets.string_index points here
   // NOTE: offsets.string_index points here
   u32 string_index[(offsets.string_data-offsets.string_index)/4];
   u32 string_index[];
   // NOTE: offsets.string_data points here
   // NOTE: offsets.string_data points here
   char string_data[];
   char string_data[];
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   // Unknown data, including the "special script"
   // Unknown data, including the "special script"
   u8[?] unknown;
   u8 unknown[?];
};
};


// Use one of these two structs for script_entry, depending on the game:
// Use one of these two structs for script_entry, depending on the game:


// sizeof(script_entry) == 8, (unknown and offset are packed into 1 word)
// script_entries[] array is null-terminated (ends when all fields are 0)
// script_entries[] array is null-terminated (ends when all fields are 0)
struct script_entry_boktai_1 {
struct script_entry_boktai_1 {
   u32 id;         // script id
   u32 id;     // script id
  u8 unknown : 8;
   u32 offset; // top 8 bits unknown (not part of offset)
   u32 offset : 24;
};
};


// script_entries[] array is -1 terminated (ends when unknown = 0xff && offset == 0xffffff)
// script_entries[] array is -1 terminated (ends when all fields are -1)
struct script_entry_boktai_2_and_3 {
struct script_entry_boktai_2_and_3 {
   // id is implied (id = array index + 1)
   // id is implied (id = array index + 1), meaning the 1st script has ID 1, not ID 0!
  // Meaning the 1st script has ID 1, not ID 0!
   u32 offset; // top 8 bits unknown (not part of offset)
  u8 unknown : 8;
   u32 offset : 24;
};
};


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   u32 unknown;    // offset to unknown data
   u32 unknown;    // offset to unknown data
};
};
</syntaxhighlight>
= Example code (Boktai 1) =
<syntaxhighlight lang="c">
script_entry_boktai_1* script_index;
int script_count;
u8* script_data;
char* string_data;
u32* string_index;
// ptr = pointer to script_directory
void open_script_directory(u8* ptr) {
  // skip "unknown" field
  ptr += 4;
  script_index = (script_entry_boktai_1*) ptr;
  // skip over script index
  while (true) {
    script_entry_boktai_1* entry = (script_entry_boktai_1*) ptr;
    ptr += 8;
    if (entry->id == 0 && entry->offset == 0) {
      break;
    }
    script_count++;
  }
  script_data = (u8*)(ptr + *(uint32_t*)ptr);
  string_index = (u32*)(ptr + *(uint32_t*)(ptr + 4));
  string_data = (char*)(ptr + *(uint32_t*)(ptr + 8));
}
char* get_string(int id) {
  // top bit is unknown, always seems to be 1?
  u32 offset = string_index[id] & 0x7fffffff;
  return string_data + offset;
}
u8* get_script(int id) {
  // NOTE: you should use a binary search (script_index is sorted by id)
  for (int i=0; i<script_count; i++) {
    script_entry_boktai_1* entry = script_index + i;
    if (entry->id == id) {
      // +4 to skip over the "special_script_offset" field
      return script_data + 4 + (entry->offset & 0x00ffffff);
    }
  }
  return NULL;
}
</syntaxhighlight>
= Example code (Boktai 2 & 3) =
<syntaxhighlight lang="c">
u32* script_index;
char* string_data;
u8* script_data;
int script_count;
u32* string_index;
// ptr = pointer to script_directory
void open_script_directory(u8* ptr) {
  // skip "unknown" field
  ptr += 4;
  script_index = (u32*) ptr;
  // skip over script index
  while (true) {
    u32 script_offset = *(u32*)ptr;
    ptr += 4;
    if (script_offset == 0xffffffff) {
      break;
    }
    script_count++;
  }
  script_data = (u8*)(ptr + *(uint32_t*)ptr);
  string_index = (u32*)(ptr + *(uint32_t*)(ptr + 4));
  string_data = (char*)(ptr + *(uint32_t*)(ptr + 8));
}
char* get_string(int id) {
  // top bit is unknown, always seems to be 1?
  u32 offset = string_index[id] & 0x7fffffff;
  return string_data + offset;
}
u8* get_script(int id) {
  if (id <= 0 || id > script_count) {
    return NULL;
  }
  u32 offset = script_index[id - 1];
  return script_data + 4 + (offset & 0x00ffffff);
}
</syntaxhighlight>
</syntaxhighlight>
Retrieved from "https://boktaihacking.net/wiki/Special:MobileDiff/63"