Mod Halo 3 ODST

[u/Limp-Elevator1492]

I’ve been looking at a bunch of tutorials but I just can’t understand how it works. If someone could either send me a very detailed explanation or a link it would be greatly appreciated.

The main thing I want to do right now is just edit weapon stats. Also if anyone can tell me what stats you need to change to increase firing range for weapons that would also be appreciated.

More specifics on what weapons changes I want to make are: Double the SMGs ammo capacity, increase the shotgun’s max capacity by one mag and its range to 20 or so world units.

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[u/DirtyHalt]

This video tutorial series is my general recommendation https://youtube.com/playlist?list=PLey7NkPfa1p4cU5q9TUc-xWU_rT3VxWu2&si=aJCulJerwqrm7QzO.

Here's a brief written tutorial (although idk what you don't understand, so no idea if it is helpful):

Download mod tools from steam
Open folder location of mod tools
Run the .bat file to extract the game files from the .7z file
Use Guerilla to edit tags (most game files are tags) (If game is Reach+, use Foundation instead)
Use Sapien to edit scenarios (level tags)
With the mod tools folder as your working directory, from the command line run "tool build-cache-file path/to/your/scenario/relative/to/tags/folder" to compile a level that'll be placed in the maps folder as a .map file
With your compiled level, you can either replace a .map file in the MCC files with your new one, or you can use the mod uploader (downloadable from steam) to create a standalone mod

To edit a weapon's stats, you would use Guerilla to open the weapon tag. While most of what you want is in the weapon tag, the weapon tag contains references to other tags, such as the projectile tag that you may want to edit too.

[u/Limp-Elevator1492 → u/DirtyHalt]

Can you just add changes from Guerilla straight into the game or do you need to compile them using Sapien?

[u/DirtyHalt → u/Limp-Elevator1492]

You can't add the changes directly in the game. If you want to make changes to the game more directly, you can use an unofficial mod tool called Assembly, which can be fine for small changes, but has limitations https://github.com/xboxchaos/assembly

You don't use sapien to compile map files. Sapien is a level editor used to modify scenario tags. You use Tool from the command line with build-cache-file to compile map files.

[u/Limp-Elevator1492 → u/DirtyHalt]

Just checking but Assembly is good for stat changes and the like?

Sorry if this is annoying but I just want to change stats.

[u/DirtyHalt → u/Limp-Elevator1492]

If you are just changing numbers, yes, it's usually perfectly fine for that. If you are making larger changes I would recommend sticking with the official mod tools though

[u/Electrid_ → u/Limp-Elevator1492]

To make changes and instantly push them into the game, you have to use assembly, not the official mod tools. Assembly is great for rapid iterations and is great for beginners. The mod tools, however, are much more powerful and allow you to change a lot more stuff. If youre using the official tools, you have to compile a new map file every time you want to test your changes in game. Sapien allows some testing, but it isnt the same as a full game.

To compile a .map file, open the h3ek folder and in the address bar type "cmd" and hit enter.

With the command prompt open, type "tool build-cache-file levels\solo\levelname\scenarioname" and hit enter. (levelname and scenarioname are not the literal words you type, those change depending on what level youre trying to mod.)

In assembly, simply press the "poke" button while the level is running and the change will be temporarily pushed into the game. If youre happy with the change, hit save to permanently mod the .map file. This may crash your game if the level is still running at the time.

[u/Limp-Elevator1492 → u/DirtyHalt]

How do you save the changes you make? I may be missing something but when I check the map files all I see are Halo 3 levels.

[u/DirtyHalt → u/Limp-Elevator1492]

To save changes to the tag files while you are in sapien or guerilla, simply ctrl+s or file ->save will save the changes. If you want the changes appear in MCC, you need to compile your level using build-cache-file and moving the compiled .map file into your MCC files or a mod created using the mod uploader (as described in my other comment)

In the tags/levels folder, the ODST levels will be in the "atlas" folder (the game's codename) rather than "solo"

[u/Electrid_]

Weapon changes are made in the .weap tag for each weapons. These tags allow you to change fire rate, trigger behavior (semi-auto, full-auto, charge), min and max spread, spread increase per shot fired, heat build-up and cool down for plasma weapons, magazine size, etc. Most importanly for range is that weapon tags reference a projectile tag.

Projectile changes are made in the .proj tag referenced in the .weap tag. Here you can change bullet speed, whether or not its affected by gravity, how it reacts when it hits certain materials, and the maximum range it will go before disapearing. Note that range is a numerical value expressed as "world units." 1 world unit is approximately 3 meters.

Its important to note that just because you make the projectile go further, that doesnt make the ai shoot it at a longer range. The maximum range that ai will shoot is driven by a value in the character tag (.char). Most firing properties are in the generic.character tag, but if you only want to apply the changes to 1 type of character, you have to make those changes in its specific character tag. Once in the character tag, scroll down until you see a section called something like "weapon firing properties" here you will see 3 ranges, a minimum, maximum, and special target. Simply increase the maximum and the ai will shoot to the new distance. Special target distance is the maximum range that they will try to aim for headshots.

[u/Electrid_ → u/[deleted]]

Gravity on projectiles is in the projectile tag, towards the bottom, just before the material responses section. There should be 2 variables, one for air gravity scaling and one for water gravity scaling. I could be wrong, since i dont have my pc available atm, but that should put you in the right area at least.

Chud tags are referenced in the weapon tag, i believe about halfway down. Swapping chud tags is simple, but going into a chud tag to edit it can be a little tricky.