Sonic Chaos Hacking

This game needs some documentation doesn't it? So since I'm taking a break from my Sonic 1 SMS disassembly (for now xP) I decided to look into Sonic Chaos, since there seems to be no documentation on this game. These are my notes (I'm still adding more info. to them as I speak. xP) And yes, I did disassemble Sonic Chaos, but I'm not releasing it to the public. (Yet. xP)

<div class='codetop'>CODE</div><div class='codemain' style='height:200px;white-space:pre;overflow:auto'>Sonic Chaos Master System
$104F- This is where Sonic's animations start. The first byte determines which frame to use.
The second and third bytes load his mappings, whereas the fourth one seems to do nothing.
So, Sonic's first walking animation looks like this in a hex editor:
04 00 80 07
$11D3- This is where Tails' animations start. See above on how the game loads the animations.
$45D0- Allows the player to "stick" to slopes, but he can't jump.
$5A18-$5A1E Intro Data (Collision and art specifically.)There's always a null
byte before each byte of data.The first three bytes determine
what mappings are to be drawn, and the next byte loads the collision. Changing this byte will result in the
death of Sonic, and the intro sequence ends only if 1/2 buttons are pressed.</div>
These older notes are inaccurate, please read the newer ones. :v:

 

Time for a brief update. Though later on today, I'll be adding more so expect this post to be edited.
Edit: Added the Demo header format. Told you I'd edit this post. xP Also added, HUD layout. Also I'll be releasing my disassembly sometime soon.

Code (Text):

1. $8D0-$AC0 Level Select Text
2. $AF6-$C28 Sound Test Text both are in ASCII.
3. $2499- Initiate Port 1 (Joypad Port)
4. $24A9- Controls Sonic/Tails in Demos.
5. $2BD6- Demo Time, Word. determines how long a demo should play. The lower the value, the shorter
6. the demo.
7. $2C72- This is where the demo headers start. This is the format and the first demo header:
8. Level Bank Control Sequence Pointer
9. $02,&nbsp;&nbsp;$1F, $00, $94
10. $29C4- HUD Layout each icon has four lines of three bytes. Format is as follows (Note this is the Life Icon
11. layout, and is the first one in the array):
12. hpos vpos char
13. $10, $28, $2E&nbsp;&nbsp;
14. $10, $20, $34
15. $10, $10, $48
16. $10, $18, $4A
17. So if you like having the life icon in the bottom left hand corner like the previous games, you would change
18. the horizontal postion to $AF, as that's the position on screen the life icon is located at in the older games.
19. It's as simple as that.

Hopefully my notes help a bit for now. :v:

 

Well that would certainly help people using Aspect Edit, I didn't know about his notes. :v: Well in that case, later on today I'll post where the music starts and then work on my disassembly until it's ready for a release. (Which should be soon since I've been identifying and labeling things non stop. ^_^) Also shouldn't the notes be on the wiki?

 

Whoops I meant not exactly where their data starts, but the offsets that determine which song to play in which act. ^^' Since you didn't document all their data, if you don't mind could I expand upon what you've found? Anyway, they start at offset $18BA and end at $18E0. Also didn't the GG prerelease have a weird version number too? I remember the thread you posted a few months back about SMS Power!'s release of that version and I believe it was Evilhamwizard that pointed it out.

 

Well, I just started to hack the Game Gear version too. So I'll change the name of this topic to a general Sonic Chaos hacking thread. :v: It shouldn't take too long to find the GG offsets, since I've disassembled that too I'll compare. But I will say this, I won't have any time to work on this tomorrow, until late (after 1:00 a.m. CST) but I usually hack late anyways and I'm already comparing offsets so you might see an edit (since I don't like double posting.) Edit: the level music for the GG version starts at $18ED to $1922, sorry I forgot to post that. :v: Edit 2: Might as well add the ASCII text location for the Level Select screen and Credits:

Code (Text):

1. The ASCII text in the Game Gear version is located here:
2. Level Select: $980-$B00
3. Sound Test:&nbsp;&nbsp;$B30 "Sound Test" text $850 "Sound Select" text
4. Credits: $6A8B9-$6AABB

 

So I started comparing tonight, and noticed something. Some things are located at the same offset. This is my very small list of things that are similar, but I'll add more later.

Code (Text):

1. $10000 Art - Sonic
2. $399A0 Art - monitors
3. $2FD00 Art - smoke puff from monitor/enemy
4. Level layout for THZ1, THZ2 starts at the same locations in both games. ($48000 and $48BA9)

Also thank you nineko for creating the wiki page, even if it's a WIP. :D I have to admit, I suck at editing the wiki, except for making minor edits. :v:

 

So some of Hivebrain's notes are inaccurate. $38000 is where the collision data starts. It determines to where to use solid tiles and adds 7 after each entry, though I'm not exactly sure why it does that. (Perhaps for compression/decompression?) This is the same in both versions btw. Here are the id #'s of each tile:

Code (Text):

1. $82- Solid
2. $83- Not Solid
3. $84- Behaves like springs (Spring Collision?)
4. $85- Seems to do nothing, but shifts the level down a few pixels after the player dies
5. $86, $87- Similar to $82

Also the compressed art for the Motobug in THZ is located at the same offset in both versions $25AB0, but the HUD numbers and Km/H compressed art is located at $1F7C0 in the Game Gear version.

 

I've found out where the Level headers start. Here are my notes:

Code (Text):

1. $5082-$52F9 Level Headers these store the mappings for each level, as well as layout data, and character
2. start positions. Each two bytes store the pointers for each level's 32x32 mappings. They are bellow:
3. $5082- THZ
4. $5084- GH
5. $5086- SEZ
6. $5088- MGHZ
7. $508A- APZ
8. $508C- EEZ
9. Level Layouts for each Zone/Act start at $50A8 and end at $50C4.
10. In the GG version, the Level Headers start at $5139 and end at $53B0. The 32x32 mappings are bellow:
11. $5139- THZ
12. $513B- GH
13. $513D- SEZ
14. $513F- MGHZ
15. $5141- APZ
16. $5143- EEZ
17. Level Layouts for each Zone/Act start at $515B.