[Script✓] in GBA FIreRed script, is it possible to "dereference" a variable when passing as a parameter to a function?

setwildbattle SPECIES_SNORLAX, 30

Click to expand...

setvar VAR_TEMP_0, SPECIES_SNORLAX
setwildbattle VAR_TEMP_0, 30

bool8 ScrCmd_setwildbattle(struct ScriptContext * ctx)
{
    u16 species = ScriptReadHalfword(ctx);
    u8 level = ScriptReadByte(ctx);
    u16 item = ScriptReadHalfword(ctx);

    CreateScriptedWildMon(species, level, item);
    return FALSE;
}

jibodagrey said:

been using the pret disassembly of firered to make some changes to the game.
ive got to a point where i write a value into a temp variable and attempting to pass that variable to a function that is expecting a literal value.

for example, setwildbattle is normally used like this

but if you did something like this

Code:

setvar VAR_TEMP_0, SPECIES_SNORLAX
setwildbattle VAR_TEMP_0, 30

and since setwildbattle is defined like this in c

Code:

bool8 ScrCmd_setwildbattle(struct ScriptContext * ctx)
{
    u16 species = ScriptReadHalfword(ctx);
    u8 level = ScriptReadByte(ctx);
    u16 item = ScriptReadHalfword(ctx);

    CreateScriptedWildMon(species, level, item);
    return FALSE;
}

it will try to use the variable index as the species id.

my question, is there any way to pass the value stored in a variable to a function from script that would not require writing a new function in c that calls VarGet with the variable index?
ive looked through the source and havent noticed anywhere this is actually done so i wouldnt be surprised if i have to keep my initial solution of just writing a new function, but still curious.

Click to expand...

u16 species = VarGet(ScriptReadHalfword(ctx));

jibodagrey said:

been using the pret disassembly of firered to make some changes to the game.
ive got to a point where i write a value into a temp variable and attempting to pass that variable to a function that is expecting a literal value.

for example, setwildbattle is normally used like this

but if you did something like this

Code:

setvar VAR_TEMP_0, SPECIES_SNORLAX
setwildbattle VAR_TEMP_0, 30

and since setwildbattle is defined like this in c

Code:

bool8 ScrCmd_setwildbattle(struct ScriptContext * ctx)
{
    u16 species = ScriptReadHalfword(ctx);
    u8 level = ScriptReadByte(ctx);
    u16 item = ScriptReadHalfword(ctx);

    CreateScriptedWildMon(species, level, item);
    return FALSE;
}

it will try to use the variable index as the species id.

my question, is there any way to pass the value stored in a variable to a function from script that would not require writing a new function in c that calls VarGet with the variable index?

Click to expand...

Anon822 said:

Modifying the function to also accept variables is simple, just do:

Code:

u16 species = VarGet(ScriptReadHalfword(ctx));

This works because VarGet actually returns its parameter if it's smaller than VARS_START(=0x4000), so the above code will work with both literal values and variable IDs, as long as your literal values are smaller than 0x4000.

Click to expand...

Lunos said:

https://github.com/pret/pokefirered/blob/master/asm/macros/event.inc#L989-L991
https://github.com/pret/pokefirered/blob/master/src/scrcmd.c#L1733-L1735

Click to expand...

bool8 ScrCmd_loadvar(struct ScriptContext * ctx)
{
    u8 index = ScriptReadByte(ctx);
    ctx->data[index] = VarGet(ScriptReadHalfword(ctx));
    return FALSE;
}