Under the Surface of Classic Sonic @SCDDeconstruct

All about programming, unused content, and more in the Classic Sonic games! Joined October 2022

Tweets

1K
Followers

3K
Following

4
Likes

23

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

@Conradd72371258 Pretty much.

1 0 0 49 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

There exists a collision bug where the check used to prevent Sonic from clipping on top of a surface he's too far below from isn't done if he's moving horizontally in the air. This can easily be seen if you put a solid object on a top solid surface and hit it from the bottom.

2 7 65 2K 8

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

@Conradd72371258 Hard to say. Chaotix uses a different engine from the mainline games, and it's not nearly as documented as them.

1 0 0 64 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

...and Sonic 3 & Knuckles.

2 1 3 263 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

...and Sonic CD...

1 1 3 297 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

@LittlePlanetCD If anyone is curious about how this jump works, check out this explanation. Note that the 2011 remake actually can't do this without modding it. x.com/SCDDeconstruct…

Under the Surface of Classic Sonic @SCDDeconstruct

3 years ago

Here's a visualization/explanation of this in video form.

0 9 48 2K 0

0 0 1 140 1

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

2 months ago

@mothnaman @Needlen0se @ParapastaCD @LittlePlanetCD It should, yes. It's a direct port of the original assembly code, unlike the 2011 remake.

1 0 1 46 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

12800 = 50 * 0x100

0 0 3 408 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

Here's a silly difference between the 510 and 0.28A (512) prototypes of Sonic CD. Special stage rings always appear in 510, but never in 0.28A. 0.28A added a ring count check, but only checked the top byte. As a result, they can only appear if the player has at least 12800 rings.

1 4 20 924 3

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

(You can find the hack here: sonicresearch.org/community/inde…)

0 0 5 429 1

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

There's a ROM hack of Chaotix called Knuckles' Clackers by GenesisDoes that reimplements loops, and even uses the masking sprite... but it still illustrates the problematic nature of loops with the tethering mechanic.

1 2 33 686 2

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

Loops were planned on being implemented in Chaotix, even being present in prototypes... yeah, I can see why they were removed (footage provided by @MDTravisYT)

3 18 144 3K 23

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

Here's the highlighted line from the decompilation: git.sr.ht/~benoitren/son…

0 0 5 502 0

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

I looked into this and saw from the decompilation that the stage ID check is messed up. The original Sega CD version checks if the stage is Palmtree Panic act 1 (zone ID 0, act ID 0), but the 90s PC port checks if the zone ID is 255 and if the act ID is 1...

𝗠𝗲𝗹𝗹𝗼-𝗡𝗼𝘃𝗮 @Mellon_Nova

3 months ago

@SCDDeconstruct For some reason the PC96 version doesn't disable the Signs in both Past and Future versions for the beginning portion

1 0 10 3K 2

1 2 55 2K 11

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

@chrisprice @Mellon_Nova I actually might look deeper into this. I did notice that the 712 prototype had the same bugged special stage 1 background palette cycling as in the PC version...

0 0 4 173 1

View Details

Under the Surface of Classic Sonic @SCDDeconstruct

3 months ago

There's a hidden tunnel that can be found right towards the end of the 3D loop section at the beginning of Palmtree Panic act 1 that I'm not sure is even accessible via normal means. Anyone have any ideas?