The Bears Pit: Vanilla Modding » 4 extra bytes in STCIHeader structure

Home » SIRTECH CLASSICS » Jagged Alliance: Unfinished Business » Vanilla Modding » 4 extra bytes in STCIHeader structure

Show: Today's Messages :: Polls :: Message Navigator

4 extra bytes in STCIHeader structure[message #137198]

Mon, 30 April 2007 12:51

Trogdor

Messages:2
Registered:February 2007

I noticed that cUnused in STCIHeader has 4 extra bytes.
The only reason why STI files are loaded correctly is because after each read comes a correct seek.
Is there any reason to keep those 4 bytes as it seems that their only purpose is to make the structure bigger?

Report message to a moderator

Civilian

Re: 4 extra bytes in STCIHeader structure[message #137239]

Mon, 30 April 2007 22:32

Lesh 2

Messages:107
Registered:September 2006
Location: Izhevsk, Russia

This is a common practice to have some bytes reserved in data structures for future creativity. Later, if developer adds some data to structure, he simply reduces amount of reserved bytes, so structure does't change its size. Otherwise, he has to redo all that data (read in old format, convert/copy to new format in memory and save in new format). Reserved bytes can save a lot of time.

So you can use up to 4 bytes for your purposes.

Report message to a moderator

Sergeant

Re: 4 extra bytes in STCIHeader structure[message #137357]

Wed, 02 May 2007 11:36

Trogdor

Messages:2
Registered:February 2007

No, what I meant was that the structure exceeds the the header size in the sti files.
10 of the 14 cUnused bytes are present but the last 4 overlap with the palette data.

And STCI_HEADER_SIZE is 64 even thought the structure is actually 68 bytes with those 4 extra.

[Updated on: Wed, 02 May 2007 11:45] by Moderator

Report message to a moderator

Civilian

Re: 4 extra bytes in STCIHeader structure[message #137384]

Wed, 02 May 2007 16:13

defrog

Messages:234
Registered:March 2004
Location: Austria

without reading the source, it has been a while. It shouldn't be a problem if the unused is at the end of the struct and is really not used.

Only problem I could see is would be if the struct size was used to index into the file.

I could be possible that the struct was extended after the resource files were generated. If this comes out of the standard gaming platform headers, then you should remember this was not solely for this game...

Report message to a moderator

Sergeant 1st Class

Re: 4 extra bytes in STCIHeader structure[message #138748]

Mon, 14 May 2007 14:37

BasiC_101

Messages:27
Registered:September 2006
Location: South Africa

Cool

Report message to a moderator

Private 1st Class

Previous Topic:	Somewhat far out, but... OGRE 3d engine + JA2?
Next Topic:	Errors in compiling: JA25 source

Goto Forum:

-=] Back to Top [=-

Current Time: Sat Jun 13 03:01:41 GMT+3 2026

Total time taken to generate the page: 0.00665 seconds