Community Project: Model Research

[grimdoomer]

Ok, Ive been wanting to look into animations for halo 2, so I started working on a model viewer to aid in the process. First I was looking around for some updated mode plugins, and I stumbled across neodos green mach effect plugin. I noticed he delete 5 reflexives for that tut and I new this was completly wrong, especially when one of the relfexives was part of model raw. So here is what I have found based on that.

Green Mach Effect Reflexive
So I found the one reflexive that is needed to remove the green mach effect, then I looked into it more. I noticed that it has 3 fields, short, short, int. Now the first short is always 0 and doesnt seem to be used. But the next two values work like this:

int = int + short

So if the int is 5, and the short is 3, the int in the next chunk will be 8. It works like this for every chunk. Now if this pattern is broken, the green mach effect goes away. But I would like to know where these values came from, and why when I have say 8 machines spawned, only 2 or 3 may be green.

Permutation Raw
Ok this is known as model raw 2, wich has never been needed in the past. Now, I noticed this reflexive is only present on machines, most likly why neodos deleted it. While I was looking at it, I notced it is very different from Model Raw 1. The first few values in the reflexive seem constant through out machine models. Then the third reflexive has 4 byte values, wich seem like indexs to something, faces? I'm not sure. Now the permutation raw data only has 1 resource block were model raw 1 has 8. When looking at the raw block in Hex, it seems like the resource block is 10 bytes long, and I have no idea what is in it. But there is some kind of index. I also belive that the data in this block is compressed. The reflexive with the 5 bytes maybe be connected to this some how.

Research Needed
- What is Permutation Raw? It is no longer used.
- Why do only Machines have it? Unknown.
- How is it structurly Layed Out? Indexs, purpose unknown.
- What does the 5 byte reflexive have to do with it? No longer Used.
- Where do the values in the Green Mach Effect Reflexive come from?
- How are they used with Permutation Raw? Permutation Raw is no longer used, possibly no relation.

Here is my updated mode plugin.
Download

[xzodia]

int = int + short

So if the int is 5, and the short is 3, the int in the next chunk will be 8. It works like this for every chunk.

That sounds like offset + size...

As for the permutation raw, it is my understanding that its for...well permutations of the model such as various damage levels, but that can't be right if only machines have it. Are you sure about that?

[grimdoomer]

int = int + short

So if the int is 5, and the short is 3, the int in the next chunk will be 8. It works like this for every chunk.

That sounds like offset + size...

As for the permutation raw, it is my understanding that its for...well permutations of the model such as various damage levels, but that can't be right if only machines have it. Are you sure about that?

Yes, only machines have it. So maybe its some sort of Machine Raw thing? As for the offset + size, that could be possible, but what exactly is in the machine raw?

[grimdoomer]

Well I have neen conducting some tests, and here is what I have figured out.

1) The Permutation/Machine Raw reflexive is never used, and the raw is never loaded nor buffered. I took a clean containment, changed the gates machine raw offset to some random number. The map loaded and it looked fine, I could open it and the game didn't freeze. I also set the offset and size to 0, same effect.

2) That 4 byte reflexive, I though it was a ARGB struct so I changed every chunk to A:0 R:255 G:0 B:0, it looked the same in game.

3) When comparing the looks of a gate with and without the machine raw, side by side, with vehicles one them, they looked exactly the same.

Conclusion:
The Machine/Permutation reflexive is no longer used in the retail game and the raw is not loaded nor buffered.