Sonic 1 iPod (Video/5G) Port Analysis

Decided to make a post for this because maybe someone else who's interested can have a crack at this.

As some of you know, Sonic 1 was ported to the iPod Video (5G and up I suppose, the click wheel stuff) a few years a go. In comparison to the other "ports" to the GBA and mobile phone platforms, this is the most accurate. The physics are virtually identical to the Megadrive version, all original graphics are present, and the original music and sound effects are used. Now of course, this port still does things differently in comparison to the Megadrive version. But first, let's break down the data files you can find in this port.

Folders:
a.) Executables - there are two executables in this folder, both are encrypted and can't be read for strings. You can also find the digital signature file for both executables in here as well
b.) Resources - the description and instruction pages are kept here in multiple languages

Every other data file is kept in the root directory of package:

Files:
a.) z#a#map.bin files - the mapping files for each act for the six zones, the first # stands for the zone number while the second # stands for the act number.
b.) rserver.bin - no idea, appears in every iPod game I think.
c.) Manifest.plist - used for backing up the game in iTunes?
d.) Manifest.plist.p7b - same as above
e.) ##.m4a - music files, the ## correspond to the number in the original version's sound test, the zone/special stage plays for 10 minutes, for some reason the 1up bgm isn't here and the emerald get bgm is track number 94, not 93, track 93 is missing all together.
f.) 8B.mp3 - for some reason the game ending cutscene bgm is the only mp3 file here.
g.) sonicicon.raw.lcd5 - icon that appears while selecting the game from the iPod menu
h.)sonic.raw.lcd5 - the load screen, I think
I.) z#m - no idea what these files are, there's no file extension there's one for each of the six zones, all have the same file size 41kb
j.) iTunesMetaData - data for iTunes
k.) iTunesArtwork- artwork for iTunes

Then the rest are data files that store data like graphics:

Data files:
a.) z##tbnk.dat - graphic bank files for the tiles, can be viewed in tile molester, one for all the playable stages (sp = special stages, the 7th "zone" is the final zone and the game ending cutscene, z0 is the title screen)
b.) z##at.dat - unsure what these are
c.) z##bgtbnk.dat - graphic bank files for the background in each zone
d.) sndbnk.dat - sound effects bank, the sound effects are recorded in .wav format, the naming scheme for each file in the bank is similar to the audio banks used for the collections released by digital eclipse.
e.) logobnk.dat - Sega logo and Sonic Team Presents graphics
f.) gentbnk.dat - "common" graphics bank, Sonic's sprites, the hud, the rings, tv boxes, etc are here

Like I said there are differences between this and the original version:

1.) There are no gameplay demos after the title screen, it just sits at the title screen until you press start.
2.) The music doesn't speed up if you get the speed shoes.
3.) Even though the BGM for the end credits exist, I don't remember there being an end credits (yes I played and finished this port).
4.) There is no parralax scrolling in the backgrounds. The background is just one layer.
5.) I feel as if Sonic moves a bit fast through the air if he does a normal jump while moving, but it could be just me.
6.) While the "Sonic Team Presents" graphic is the same as the MD version, the Sega logo doesn't have that light blue wave thing like the original does (but oddly enough the uncompressed Sega sound from the original version is used instead of a higher quality one, the pitch is a little higher too)
7.) There's a how-to-play screen when you start a new game that shows how to play the game with Sonic in GHZ Act 1.
8.) Pressing any button on the title screen will move the title screen logo up and display options to start a new game or finish where you left off.
9.) There are no cheats (confirmed, I asked the original developers of the port and they said that they didn't put any cheats in the game).
10.) The screen fade effect is different.

These are the only differences I can think of for the moment.

Now here's some more interesting things about the port in general.

All the unused graphics that were present in the original version (the goggles, the monitors, the extra Sonic frames, etc) are present in the graphic banks. The only thing I couldn't find was the "PRESS START BUTTON" graphic for the title screen, but it might be around somewhere. One thing I noticed, as far as the naming scheme for the zone files go, it uses the original zone order that was set in place for the game like the original MD version does (GHZ first, LBZ second, etc). Like I said before, the game says that zone 0 is the title screen and zone 7 is the final zone and ending cutscene. But here's the odd part, z71tbnk.dat is the graphics bank for the Final Zone (which for some reason includes all the tiles used for Scrap Brain instead of just some of them) while z73tbnk.dat is the ending cutscene. Now, where the hell is z72tbnk.dat?! I don't think this is anything too special, but maybe someone with knowledge of the internals of the original game can think of something better than I can.

Oh, and remember how the mobile phone port included unused tiles such as the planets/ufos in Marble Zone? Well, they're present here as well:

http://I.imgur.com/qyw32.png (it's the middle of the black circle I drew)

Another interesting thing I noticed is that the unused wrecking ball is in the Marble Zone graphics bank as well! I checked some of the other zones besides GHZ and it's not there. So maybe they had the wrecking ball in other zones at one point?

There's probably some other cool stuff as well. But as you can see from the picture above, I can't get the correct palette to show up in Tile Molester. I do have an image of what gentbnk should look like though:



As for the music being recorded to loop for 10 minutes, I think they did this as a way to optimize performance. Whenever the music changes (like for invincibility, etc) the game will hang for like 3 seconds. And then it'll hang again to put the original zone music on again. The same can probably be said as to why the 1UP BGM isn't present, because that could probably make the game way more annoying than it already is with it hanging almost all the time.

With all that aside, I do know that source code was given to the developers of this port from Sega of Japan. Either the source code was similar to the mobile phone port, I don't know, but either way - they did a pretty good job on it.

I think I might have more on this, I just have to refresh my memory again. This whole topic was kinda a "last hour" type of thing, so I didn't really organize the content. So I apologize if some things don't really make sense.

I would like to post the data from this port without the music so people can look at it, but I'm afraid to.

 

Yep, also - the game starts you off with 5 lives instead of 3. Very nice of them. :P

Also, I noticed that this unused object is packaged in every graphic bank for act 3, or where the bosses are located for each zone:



Maybe it's an early version of the capsule?

Also, I can't seem to find Splats anywhere. :\

 

Wow, I have no idea. I also noticed a "stoned" Sonic there too.

Also check this. This looks familiar from something debug related, but does anyone know what it is?



It's the TM stuff I circled in red. It only appears in the graphic bank files for Star Light Zone.

 

Ah, I see. I checked the files in a hex editor and I noticed that there wasn't any compression, so I'm sure you're right.

Also, the conveyor belts in Scrap Brain zone never went diagonally, right? I checked the graphics bank for Scrap Brain Act 1 and I noticed there were tiles for the conveyor belt to go diagonally. Not sure if these graphics exist in the final somewhere, but I remembered this being shown in prototype shots and not featured anywhere else in the final game.

 

Uh, I know it's very old news. :P

What's news to me is that it's included with every Act 3 graphics bank, hinting that maybe it's something to do relating to bosses. Before, we said it was an unused object for Star Light Zone - but as you can see, I can find this graphic in every zone.

Also yeah, about that diagonal conveyor belt. I was just going to say that I remembered a diagonal belt with spinning platforms. But the thing is, I think I also saw the tiles in the Act 2 graphics bank as well. But then again, sometimes it seems that each graphics bank has common tiles it loads regardless even if it's used. The title screen for example, has more tiles for Green Hill Zone (like the flowers and some of the platforms), but of course they aren't used.

I wish we could view these graphic banks with a proper palette. Some of the smaller tiles look interesting but I can't make them out because the colors are messed up.

EDIT: Also, the crystals/stalactites in Labyrinth Zone. The only difference between them in the prototype versions is that they were smaller, right? Because if I remember, I think I saw tiles for both the big ones that are used plus smaller ones. It's been so long, so help me out. I have to check the banks for LBZ later.

EDIT2: Here's LBZ Act 1's bank. You can see the crystals/stalactites starting from the middle to the lower bottom. I can see similar ones from the shots, but I think my eyes are playing tricks on me. But someone may think differently. What do you guys think? Also, do you see anything else that's odd in here?

Here's a proto shot with some in for comparison.