Ooh very nice, I don't think there's ever been any layout hacks for any version of 3D (prove me wrong Retro :-) ) any step in that direction is exciting. Any unusual out of bounds areas spotted?
There's a misplaced loop in Green Grove Zone Act 2, but it's otherwise quite clean. Which probably suggests they had fairly smart tools for making maps, i.e. they weren't placing every tile by hand. I would have guessed that anyway since it would be a nightmare otherwise, but hey.
3D Blast has many unused areas of certain maps. Spring Stadium I remember has an area where graphics are planted in the middle of nowhere. I never could quite figure out the exact format of the layout. It was always a strange format to me (three bytes per 32x32 block I think?). So kudos to having solved that! Maybe a map editor is coming next?
I do already have a Tiled addon working for loading and saving the graphical layout... but that's just the art, I haven't quite figured out collision (although the start of each MAP file has a 128x128 image of the stage when viewed at 16bpp, so that could be the collision) and I have no idea how objects work. I kind of have sprites figured out, but not fully. Also, all of the offsets for data in the MAP/GFX files are hardcoded in the game, so any kind of advanced editing is going to be a huge pain (I wrote a tool to dump all the offsets from the game as it was running). The chunk format is a pretty standard 16 bits per tile, YXP- IIII IIII IIII. If you were looking at the MD version, the data is probably compressed, and may also be somewhat different to what's here.
Okay, I couldn't resist. If I don't share in some capacity, it'll only get lost to time. I've attached a ZIP file containing a bunch of savestates where I modified level boundaries to allow free exploration, the hacking notes I created, and a handful of screenshots showing some abandoned areas. This stuff was originally being done toward an effort to establish a Sonic 3D Blast Hacking Guide, but I never ended up getting beyond what's available in the ZIP file. This is all for the Genesis version of the game, but perhaps might be of interest anyway.
Great stuff, if the object definitions are cracked I'm happy to crank out some more object maps like with Chaos!
Just uploaded the object versions of all the special stages for Chaos, the only minor point of interest is special stage 3, which is one giant troll. You go through five identical pipe/room with invincibility segments to bore you into a stupor, then the pipe changes to one where you have to press up to change direction and reach the emerald. If you don't, you get trapped in a loop and fail. Or maybe you can recover it somehow, not really sure. Well there's a sixth invincible monitor in the solid wall. Apparently they considered an additional troll room before sticking with just the five! :-D File:SC SMS SSZ3 Object Map.png - Sonic Retro
I started having a look at Sonic 2 SMS using the same techniques as Chaos to mess around with the object definitions. Curiously there's an out of bounds minecart in UGZ1 that's in the perfect horizontal position to be used with the first rail you encounter on the upper level (right after jumping over the first pit), but vertically it's way below the lower bound of the level. If you tweak the Y co-ordinate to be 00AE instead of 0C40 (the object definition starts at 0x78242, so to do this, set 0x78245=AE and 0x78246=00) you get a perfectly positions minecart to use on the upper level. The question is, was it shifted out of bounds on purpose as the devs felt a cart wasn't appropriate here or was this an oversight? I realise there's been an awful lot more research on Sonic 2 than Chaos and Triple Trouble, so fully expecting someone to chime in with "oh yeah, we found this in 2005!" but I thought it was curious enough to mention.
I just added objectless master system maps to the Sonic 2 8 bit page. These were a bit of a pain because Aspect Edit seems to have a bug where only for Sonic 2 maps, the bottom couple of rows of tiles are cut off regardless of how you size the map. Fortunately Esrael's Sonic 2 SMS editor doesn't do this, but it has no way to generate a png of a complete map nor can you hide objects and just get the map itself (I think?). So I ended up just generating all the maps in Aspect Edit then splicing in the bottom rows from Esrael in GIMP. Maybe there was an easier way, but it's done now! Sonic the Hedgehog 2 (8-bit)/Maps - Sonic Retro Oops, accidentally uploaded a WIP version of GMZ1, lets just quietly pretend that never happened. It's kind of interesting opening up SMS and GG versions in two tabs at the same zoom level, then flicking between them as the little changes clearly stand out. There was definitely an effort in the GG version to make the game less annoying. Springs removed, jumps made easier by removing tiles, that sort of thing. Makes it all the more baffling that they decided to make the UGZ3 boss 100 times harder. A bit of googling shows someone called PixelMarioXP has made a bunch of Sonic Blast maps with some objects. I'd love to know how they made them! Game Gear - Sonic Blast - The Spriters Resource (spriters-resource.com)
