FF7/Field/Field Script

Contents

Section 1: Dialog and Event (Halkun, Lasyan, Qhimm and Ficedula)

The First section holds the Field Script logic and Dialog data for that particular field file. The first section of the PSX DAT file (excluding the DAT header) and the data in this section are the same. A recap of the PSX DAT file format is later in this document.

The data in this section also has a header with the following format.

Section 1 Header

 struct FF7SCRIPTHEADER {
   u16 unknown1;			// Always 0x0502
   char nEntities;			// Number of entities
   char nModels;			// Number of models
   u16 wStringOffset;			// Offset to strings
   u16 nAkaoOffsets;			// Specifies the number of Akao/tuto blocks/offsets
   u16 scale;                          // Scale of field. For move and talk calculation (9bit fixed point).
   u16 blank[3];
   char szCreator[8];			// Field creator (never shown)
   char szName[8];			// Field name (never shown)
   char szEntities[nEntities][8];	// Field entity names
   u32 dwAkaoOffsets[nAkaoOffsets];	// Akao/Tuto block offsets
   u16 vEntityScripts[nEntities][32];	// Entity script entry points, or more
					// explicitly, subroutine offsets
 };

Event Script Subsection

Here we have all of the pointers tables, one for each section. Pointers are 2 bytes length. Each table has a length of 64 bytes, which means a section can have 32 scripts max. Each pointer refers to the first command of the current script. The section number N begins at the offset header_length+N*64. Note: the only way to retrieve the length of a script is to subtract the position of the next script to the position of the current script.

Cyberman 14:05, 30 Dec 2006 (CST) Unused events in the event script subsection point to a 00 RET opcode (each empty script has a unique RET opcode for it in the script). This must be strictly adhered too or the FF7 engine will crash.

Event Script

The actual script follows immediately after the aforementioned pointer tables. For a list of opcodes and their arguments, see the opcode table.

Dialog Subsection

Right after the last script of the preceding section, we find the 2 byte dialog count, followed by the dialog pointer table. Using the dialog count, you can deduce the length of the table: number_of_dialogs*2. After these 2 bytes we have the pointers for each dialog. Be aware that the pointers are relative to the table, which means you must add the position of the table to each pointer in order to find the right position of the dialog. The dialogs begin right after the table, and the code 255 means the end of the dialog. Note: some hidden dialogs are not referenced in the table!

Akao blocks

If there are any Akao offsets (as specified by nExtraOffsets and dwExtraOffsets), they follow after the dialog subsection, beginning with the four-letter AKAO. Akao blocks contain sound-related data such as the music file index for this field. In some fields (junpb_2, mds7pb_1, mds7pb_2 and msd7_w2), the Akaos are mixed with tutorials. I do not know why, but the PC version uses a separate file (junpb.tut, mds7_w.tut or mds7pb.tut) instead of these tutorials.
Note: Between dialogs and akaos there may be a padding to align the akaos section.