Thanks to Enixile for getting me started and some others for helping me lose my title as super n00b. Happy modding...This was revised and corrected by Enixile.
NOTES ON HALO HACKING
Definitions
Byte: 2 characters (0-10 and/or A-F) ex: 4c, 34, da, etc.
Word: 2 bytes ex: 1a 23, 12 34, ac 31, etc.
Dword: Also refered to as double word, integer, or int, its 2 words (hence double word) ex: 1a 23 12 34, 12 54 0a c5 etc.
Meta: The controls and data, it takes resources and uses them to do something.
Pointer: A dword that stores an offset within it. Directly from the map, it has magic added. ex: The values use in offset swapping are actually meta pointers, they have magic added.
Identifier: Also called IDENT a unique number representing a tag. It is a different value in every map. First byte is 'E'.
Offset: An address to a value somewhere in the file.
Value: Number referring to something in the code.
Tag Type: Categories that tags are put in, such as projectile tags are in the "proj" tag type.
Endians: Endian is the style the information is stored in. Big endian is stores information in a normal readable state, and little endian stores the information backwards.
Index: The offset list/tag information list inside of a map.
Tag: Any object used in the map.
Useful Programs
HMT, HMTV3, Halo Map Tools - An easy to use tool great for swapping projectiles and stuff. Also cam be used for more complex things
SE, SparkEdit - 3D map viewing and editing tool. Used mostly for placement of objects.
HHD Hex Editor - Used for editing the hex in halo maps.
HHHT, Helpful Halo Hacking Tool - Used to apply PPF patches to levels
HEK, Halo Editing Kit - A likely myth, a program unlikely to released for making levels and mods simple form GearBox Software for Halo PC. The release date is unknown and may be non existant.
Swapping Identifiers
1. Locate the Meta for whatever your changing using the offset list.
2. Locate the tag for whatever your changing. ex: jorp
3. Locate the identifier of the object your changing, Its the 4 bytes following 4 '.'s after the tag.
4. Locate the identifier for what your putting in there on your offset list.
5. Replace the ident for the original object with the ident for the second object
Finding the Index
1. Open any map.
2. Go to offset 0x10.
3. Get the int there.
4. Swap it's endian.
5. Go to the result as an offset.
6. Go to +0x28 for pc maps and +0x24 for xbox maps.
Notes on the index
Every 32 bytes is a tag page.
The first every four bytes up until 12 bytes are the tag types.
Then the next four bytes is the identifier.
After those, the next four bytes is the meta pointer.
Then finally the last four bytes is the filename pointer.
Swapping Endian
It's simply reversing the order of the bytes in groups of four.
Examples: 01 23 45 56 = 56 45 23 01; a0 d1 f2 c2 = c2 f2 d1 a0
Swapping Offsets
Swapping offsets is simply switching two tags around. You can swap anything from bitmaps to vehicles to particles to projectiles, etc.
1) Get a hex editor and an offset list, like Iron Forge's: http://forge.halomods.com/offsets/retail.php
2) Open the map you want to swap in, in the hex editor.
3) Look up the offset for the the tag you want to change on the offset list under the proper category.
4) Goto that objects offset in your hex editor.
5) Now at that offset there is a dword that should end with 40, 41, 80, or 81.
6) Now on the offset list look up what you want to go in place of that tag.
7) Replace the dword at the offset for the new dword or "value" from the new object.
Now just save the map and run.9) Enjoy!
