[Other] [Pokeemerald] Adding ONLY Hidden Abilities from Pokemon Expansion

Kobazco said:

As the title says, the project I'm currently working on doesn't need the Pokemon expansion, but I want to be able to use hidden abilities. Would someone be able to point me in the right directions either for what files in the Pokemon expansion add in hidden ability support, or a separate method of adding them in? For Pokeemerald btw.

I have the Battle engine upgrade v2 and item expansion in this decomp project if that information helps in anyway.

Click to expand...

Lunos said:

This is about all you need.
https://github.com/rh-hideout/pokeemerald-expansion/pull/1464/files

Click to expand...

Kobazco said:

Unfortunately, it seems like I need additional assistance. It seems like I've managed to get it all working (hidden abilities are appearing in my dev menu implying they are properly being assigned), but attempts to use SetMonData to alter the ability to be the Hidden one don't work and default to Ability 00 for some reason.

As an example, this is the command I have been trying to use: SetMonData(&gPlayerParty[tMonId], MON_DATA_ABILITY_NUM, &tAbilityNum); with tAbilityNum being set to 2

Click to expand...

    if (gBaseStats[species].abilities[2] && (Random() % 100) <= 50)
    {
        value = 2;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }
    else if (gBaseStats[species].abilities[1])
    {
        value = personality & 1;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }

Lunos said:

For your information, that's not a command, it's a function call. You're calling the function SetMonData and passing specific parameters through it.

Anyway, where exactly did you do this?
Ideally, hidden abilities should be set in the function where all the basic data of a Pokémon is created, CreateBoxMon.

As you can see right here, in CreateBoxMon a Pokémon is given its 1st or 2nd ability based on their personality, if they do have a 2nd ability at all.
There's many ways you can make hidden abilities (that is 3rd abilities) usable and it solely depends on your own tastes.

Here's a quick example. I slightly modified the if statement I linked above.
This would make it so there's a 50% chance that a Pokémon is generated with its hidden ability if they have one:

Code:

    if (gBaseStats[species].abilities[2] && (Random() % 100) <= 50)
    {
        value = 2;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }
    else if (gBaseStats[species].abilities[1])
    {
        value = personality & 1;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }

Click to expand...

Spoiler:

//Ability
    if (abilityNum == 0xFF || GetAbilityBySpecies(species, abilityNum) == 0)
    {
        do {
            abilityNum = Random() % 3;  // includes hidden abilities
        } while (GetAbilityBySpecies(species, abilityNum) == 0);
    }

    SetMonData(&mon, MON_DATA_ABILITY_NUM, &abilityNum);

Lunos said:

For your information, that's not a command, it's a function call. You're calling the function SetMonData and passing specific parameters through it.

Here's a quick example. I slightly modified the if statement I linked above.
This would make it so there's a 50% chance that a Pokémon is generated with its hidden ability if they have one:

Code:

    if (gBaseStats[species].abilities[2] && (Random() % 100) <= 50)
    {
        value = 2;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }
    else if (gBaseStats[species].abilities[1])
    {
        value = personality & 1;
        SetBoxMonData(boxMon, MON_DATA_ABILITY_NUM, &value);
    }

Click to expand...