Homebrew ROM Hack Applying IPS patch to CIA file

[TheMhanzLord]

Hi, I wanted to apply some mods for Fire Emblem Fates and resorted to the HackingTools9DS. All the mods went it smoothly (tested) replacing the files I needed to, but one of the mods is an IPS patch. I can't verify whether the patch worked easily and I wanted to know what's the best way to apply an IPS patch to a CIA file? Do I use Lunar IPS selecting the rebuilt CIA or do I need to patch some extracted file before rebuilding?

tl;dr how do I apply an IPS patch on a CIA file? Directily on the CIA or on an unextracted file?

 

[spitzeqc]

Luma has the ability to apply patches to (most) games on the fly. This post does a good job of explaining how to apply patches to games luma can support, but to summarize

1. On your sd card, go to '/luma/titles' and create a folder with the game's title id (if it does not already exist)
2. Drag patch files into your 'title id' folder
3. Enable game patching in luma (restart console and hold select while booting, there should be an option for game patching)

An example of this can be seen with kaeru gallery (flipnote studio 3d server replacement), and may be useful for seeing what a sample patch looks like

 

[TheMhanzLord]

Luma has the ability to apply patches to (most) games on the fly. This post does a good job of explaining how to apply patches to games luma can support, but to summarize

1. On your sd card, go to '/luma/titles' and create a folder with the game's title id (if it does not already exist)
2. Drag patch files into your 'title id' folder
3. Enable game patching in luma (restart console and hold select while booting, there should be an option for game patching)

Initially I used this method for each mod I intended to use (basically all replacing/adjusting already existing files), but the game had some input lag because of this. It might not be the case with JUST the IPS patch though.
Merging resolved that lag though, so do you know any other method to apply an IPS patch? I swear I searched a lot but it's always about rom hacks for ds each thread I found.

Also, I tried patching the whole CIA with IPS patch and it just doesn't install using FBI.

 

[spitzeqc]

If you patch the rest of the cia, but then use the ips with luma's patching, does it work?

It looks like the way patching works is it first looks on the sd card for the file to replace, and if found the file is replaced. So if you are replacing a lot of files, there will likely be a bit of slowdown. I would need to look into it a bit more, but I assume the IPS patches for luma work in a similar way (if it is needed, load the original code then apply the patch directly in memory). If this is the case, there is bound to be a solution for turning it into a cia, its just a matter of if it is user friendly or not.

My gut instinct is that applying the IPS to the proper extracted file should cause it to work, but I have not tested this

 

[TheMhanzLord]

If you patch the rest of the cia, but then use the ips with luma's patching, does it work?

It looks like the way patching works is it first looks on the sd card for the file to replace, and if found the file is replaced. So if you are replacing a lot of files, there will likely be a bit of slowdown. I would need to look into it a bit more, but I assume the IPS patches for luma work in a similar way (if it is needed, load the original code then apply the patch directly in memory). If this is the case, there is bound to be a solution for turning it into a cia, its just a matter of if it is user friendly or not.

My gut instinct is that applying the IPS to the proper extracted file should cause it to work, but I have not tested this

I didn't try the first option you mentioned but patched the GameData.bin extracted file, since a similiar patch that got surpassed by the one I'm using did have this as instruction. I'll see if the patch worked and I'll tell you, otherwise I'll try the luma method but I assume as it is the standard method it works for sure.
The game did get installed with no problems this way, I'll update later.

Found a post (gbatemp.net/threads/use-luma-game-patches-on-citra.505375/page-2) that said to de-compress the GameData.bin, patch it and then compress it again. I didn't do it though

 

[Fredwort]

Yo wondering if you ever figured this out? New to all this but just went down the same rabbit hole for Fire Emblem awakening about to open game to see if the performance is better with Luma still applying that ips patch

 

[Kwyjor]

It makes no sense to apply an IPS directly to a .cia.

Any mod that is somehow packaged in the form of an IPS probably should come with instructions on how to apply it.

 

[Fredwort]

It makes no sense to apply an IPS directly to a .cia.

Any mod that is somehow packaged in the form of an IPS probably should come with instructions on how to apply it.

Thanks for the info I am new to this I don't really understand the way the files interact with each other. The IPS file for the mod I used assumed that I would be using luma, so the only instruction is to put it in the corresponding folder. Currently had an issue installing my edited CIA due to my SD card so I won't have my answer til later

 

[Kwyjor]

so the only instruction is to put it in the corresponding folder.

Why don't you just provide a link to whatever it is you're looking at? Or rather, instructions on how to find it with Google, since new accounts can't post links?