In this case, implementing the depth check for when Sonic is moving horizontally, while fixing the issue I highlighted, would make this clip even easier. The proper fix for this would be to also check if the surface Sonic is colliding with is merely top solid, and only perform the check if it is.
However, in Lava Reef Zone, there's a set of fully solid stairs that Sonic can clip into in the same fashion, but because he'll get stopped by the next step, he'll start moving down, causing the depth check to take effect, allowing him to fall right through.
(GIF courtesy of Flamewing)
If you mean like this, then, no. The clip is possible, because floor collision is ignored when he's moving upwards, and the wall sensor is too high up in this instance to trigger a wall collision. He also isn't deep enough into the platform for the depth check to cause floor collision to be ignored.
...and Sonic 3 & Knuckles.
...and Sonic CD...
This bug also exists in Sonic 2...
This is what the missing check does, which is present when mostly falling downwards and less horizontally.
There are 4 collision modes while airborne, 1 for each cardinal direction. When he hits the rock, his Y speed is cancelled out while still moving right. Since he's technically colliding with the floor and the check isn't done, he clips on top of the surface, right into the rock.
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.
12800 = 50 * 0x100
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.
(You can find the hack here: sonicresearch.org/community/in...)
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.
Small fun fact, there's an unused sprite in the final build that would have acted as a sprite mask by drawing on top of the character sprites, but set to use a low priority color so that it would appear behind the loop, which is drawn by the Genesis.
Loops were planned on being implemented in Chaotix, even being present in prototypes... yeah, I can see why they were removed (footage provided by @mdtravis.bsky.social)
Seems like you can mess around with the peelout to get the collision to register, though.
I do know you can glitch the physics in the 3D loop to get you to into that area... maybe it's just a failsafe in case that section goes wrong? Can't say for sure, though.
No, you can't time travel in this area. In the present, the camera will refuse to go back once you've gone past it, and if you are in the past or future, time travel gets disabled.
Curiously, there's a couple of hidden springs around here as well, but they cannot be touched, because they are completely obscured by the ramp.
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?
The Metallic Madness act 2 demo was, indeed, rerecorded as well. The USA demo struggles while the Japanese demo gets quite a bit further ahead.
Left: Japan/Europe, Right: USA
The Metallic Madness act 2 demo was, indeed, rerecorded as well. The USA demo struggles while the Japanese demo gets quite a bit further ahead.
Left: Japan/Europe, Right: USA
The Tidal Tempest act 3 demo was also rerecorded. What I find peculiar is how whoever recorded the USA demo slowly walked to the boss while the Japanese demo caught up. Were they trying to eyeball the Japanese demo? I dunno...
Left: Japan/Europe, Right: USA
The Tidal Tempest act 3 demo was also rerecorded. What I find peculiar is how whoever recorded the USA demo slowly walked to the boss while the Japanese demo caught up. Were they trying to eyeball the Japanese demo? I dunno...
Left: Japan/Europe, Right: USA
Note the different timings. With the special stages, the demo ends when the controller data reaches an entry with the start button pressed. The normal stage demos are fixed at 2048 frames.
Special Stage 6
Left: NTSC, Right: PAL
In the PAL version of Sonic CD, the physics of Sonic were modified to more closely resemble the NTSC physics while at a lower frame rate. As such, separate demo controller data had to be recorded for the special stage demos.
Special Stage 1
Left: NTSC, Right: PAL
For some reason, the demo for Palmtree Panic act 1 was rerecorded for the USA release of Sonic CD. Here's a comparison showing the differences.
Left: Japan/Europe, Right: USA
Thanks for the 200 followers :)
Sorry that I've not been posting as much here. I admittedly don't really use Bluesky and I keep forgetting about this account. I should find the time to bring this account up to date.
This also doesn't apply to the special stages, but the special stages don't use separate files for the demos like the regular levels do, so there's not really anything to look into for that.
