Data Leftover

This is a sub-page of Proto:Sonic the Hedgehog 3.

The ROM contains two kinds of leftovers. Irrelevant to Sonic 3 are various references to source code and assembler linking data for Star Trek: The Next Generation: Echoes From the Past, mainly in the area where the sound driver is located.

Secondly, toward the end of the ROM are two large areas with some leftover stage layouts and palette data from various earlier builds of Sonic 3. This includes the stage layout data for Lava Reef Zone Acts 1 and 2, and the two-player Competition zones in various states of completion. The stage palette table and the data it points to for two earlier builds are both intact. The tables below describe the contents of the leftovers. Wherever a discontinuity occurs, it means that the previous data ended and what follows is an even older leftover dataset, which normally means that its beginning is missing to a certain extent, or it's a new data array in use by the game aligned to a certain region, which in this case it cuts the previous leftover data from the end.

Star Trek Lost Data (0x04CC90-0x04FFFF)#

Chunk 1 (0x1AACAE-0x1C7FFF)#

Chunk 2 (0x1EAF4A-0x1F6FFF)#

Chunk 3 (0x1FFBD8-0x1FFFFF)#

Extracting the archives from these lost regions makes it possible to have a small peek at how stages progressed over time. Generally, the stages layout didn't change significantly: Lava Reef though the visuals are very different from the final rendition on Sonic & Knuckles, its layout is very similar. The competition stages had some slight adjustments, mostly repeating the layout more or less as the game development progressed and finally shifting the layouts down by 256 pixels in some cases to add some ceiling barriers, preventing players from cheating by going over the top. The older layouts, using placeholder tiles and blocks don't specify any background with the exception of Azure Lake, which had its art already by that point. The color palettes are mostly the same in regards of the competition zones with the exception of Balloon Park which changed drastically in color tone, and to a lesser extent, Chrome Gadget having an additional gradient color in the sky.

Stages#

Lava Reef Zone#

Within the leftover data, 8 copies of Lava Reef Act 1's layout can be found, along with a copy of most of its other relevant data (palette, art, blocks, chunks, palette cycle, animated background routine, small rock locations, etc.). There is also the Act 2 layout further past the location where Act 1 is stored, seemingly used as placeholder data. The only data missing is collision and object/ring data (assuming the latter existed at this point).

Azure Lake#

Foreground
Background

This old Azure Lake has a different background, one that's more cyan and filled with flowers instead of water, resembling Sonic 2's Emerald Hill. The two lost copies of Azure Lake's data are incomplete but otherwise identical, still differing from the files that ended up in the game.

Balloon Park#

Foreground
Background
Placeholder art files

This old Balloon Park used to have different color tones, notably more purples.

Desert Palace#

Foreground
Background
Placeholder art files

Old Desert Palace has a slightly different quarter-pipe chunk leading to the lap checkpoint.

Chrome Gadget#

Placeholder art files
Placeholder art files

No art present as it's below the cutoff region at 0x1c7FFF. Only placeholder tiles and generic mappings exist from the older block.

Endless Mine#

Placeholder art files

Like Chrome Gadget, no art is present. Both layouts are identical.

Gumball Bonus Stage#

The Gumball stage data present in these lost archives is exactly the same as the version referenced by the game.

Palette Tables#

The palette block used in-game is the one on the left.

0x1E96D4 (Used)	0x1F25AE (Very Old)	0x1F4E6A (Old)
The prototype main color palette array, a large majority of which are referenced and used. It does not contain the palettes for Mushroom Valley or Lava Reef.	The oldest group of unused palettes. Hydrocity's bricks have orange/purple colors, and the outside palette for Ice Cap Act 2 does not exist. The Mushroom Valley and Lava Reef palettes are still present, and of all the Competition Zones, only Azure Lake has an entry, and early boss palettes are present as well.	Another group of unused palettes. Mostly similar to the previous one, except Hydrocity now has the final brick brown shades, an early version of Ice Cap Act 2's outdoors palette exists, and more of the Competition Zones have palettes with only Endless Mine still missing.

To do: Add the rest of the offsets and images.

Hydrocity Zone Act 1 underwater

Original	Alternate

Hydrocity Zone Act 1
The bricks in the oldest palette are red in the foreground and lavender in the background. Later palettes changed them to green and purple.

Original	Alternate 1	Alternate 2

Hydrocity Zone 2
Differences suggest that Act 2 had the exact same background as in the previous act. The finalized background doesn't fit well.

Original	Alternate 1	Alternate 2

IceCap Zone Act 1 and 2 "Cavern Area"

Original	Alternate 1	Alternate 2

IceCap Zone Act 2 "Outside" Act 2 does not have a unique palette in the oldest palette table, possibly indicating the level was entirely indoors.

Original	Alternate

Mushroom Valley Zone Act 1 and 2

Original	Alternate 1

Lava Reef Zone Act 2
Though the colors are arranged differently, the palette is somewhat similar to Lava Reef Act 2.

Original	Alternate

Balloon Park
This palette matches the final Competition Mode icon's colors.

Original	Alternate

Chrome Gadget
This palette shows an otherwise unseen part of the background, and matches the final icon's colors.

Original	Alternate

Angel Island Zone Act 1 (used in an early cutscene?)

To do: Offset for the Very Old version.

An unused AIZ1 color palette appears to be a mix between the beach cutscene and the forest interior, as if the forest background did not exist. This color palette has been removed in the version used by the prototype. It is speculated that this color palette might have been meant for an earlier AIZ background that would later be featured in prerelease footage of the Game.com Sonic Jam.

Original	Alternate 1

Early Carnival Night Zone Act 2 boss
An early palette for Carnival Night Zone Act 2's boss.

Original	Alternate

Early Launch Base Zone Act 1 boss
An early palette for the Twin Hammer miniboss.

Original	Alternate	Alternate 2

Early Lava Reef Act 1 object palette
A palette for Lava Reef Act 1 objects. It's more orange compared to the final as it fits the LRZ Badniks extraordinarily well. However, a few colors are similar or recognisable to the final version.

Original	Alternate

Early Launch Base Zone Act 2 boss
An early palette for the Launch Base Act 2 ball shooter boss.

Original	Alternate

Early Mushroom Valley Act 1 boss
An early palette for the Hey Ho miniboss.

Original	Alternate

Source Code#

Pieces of the source code for Star Trek: The Next Generation linger at various parts of the ROM. Like other prototypes, this was likely the result of the game being leftover in the memory of the compiler.

At 0xAFF0E:

                          ,WhichMessage
                Bra     @DoneInput


@InComingHail:
                Move.w  #3,WhichMessage
                Bra     @DoneInput


@ImpulseDamaged:
                Move.w  #4,WhichMessage
                Bra     @DoneInput

At 0xBFAB4:

                                                                  the screen.


DMAScrollArrows:
                Subq.w  #1,ArrowDelay                           ; Determine if arrow buffers or blanks should
                Bne.s   @NoTogg                                 ;  be DMA'ed this makes the arrows flash.

                
Move.w  #15,ArrowDelay                          ; Reset delay between flashes.
                Eor.w   #1,ArrowToggle                          ; Toggle between blanks and arrows.


@NoTogg:
                Tst.w   ArrowToggle                             ; Branch to relevent bit.
                Beq.s   @ArrowsOff


; ====== Arrows on, DMA the buffers. ======

                
Lea     UpArrowBuffer,A0                        ; Source.
                Lea     ScrollBBase+(27*2)+(21*64),A1           ; Destination.
                Move.w  #1,D0                                   ; Number of words.
                Move.l  #VDP_VRAMWrite,D1                       ; Set to write to VRAM.   
                Moveq   #2,D2                                   ; Auto increment.        
                Jsr     PushDMA                                 ; Move characters to VRAM.

                
Lea     DownArrowBuffer,A0                      ; Source.
                Lea     ScrollBBase+(27*2)+(26*64),A1           ; Destination.
                Move.w  #1,D0                 

At 0xCF970:

                Lea     ScrollBBase+($b*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Move.w  #AsciiOffset+CHR_Palette0+CHR_HighPri,D5 ; Color is different if in impulse.

                
Bra     @DoneSeperators


@NotImpulse:
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri+'.',D0        ; Place decimal points and '/' seperators.
                Lea     ScrollBBase+($5*64)+(28*2),A1           
                Jsr     Word_2GVRAM     
                Lea     ScrollBBase+($7*64)+(27*2),A1
                Jsr     Word_2GVRAM     
                Lea     ScrollBBase+($d*64)+(28*2),A1
                Jsr     Word_2GVRAM     
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri+'/',D0  
                Lea     ScrollBBase+($9*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Lea     ScrollBBase+($b*64)+(27*2),A1
                Jsr     Word_2GVRAM    
                Move.w  #AsciiOffset+CHR_Palette3+CHR_HighPri,D5 ; Set up character color.


@DoneSeperators:
                Move.w  CurrentDistance,D7                      ; Get whole part of DISTANCE.
                Moveq   #3,D6                                   ; Three characters.
                Moveq   #'$',D2                                 ; Lead with a spaces.
                Lea     ScrollBBase+($5*64)+(25*2),A1           ; Screen destination.
                Jsr     PrintVal                                ; Print it.
                Move.w  CurrentDistance+2,D7                    ; Get fractional part of DISTANCE.
                Moveq   #2,D6                                   ; Two digits.
                Move.w  

At 0xDFEF3:

                                              _No1,VIEW_NOT_FLIPPED,VIEW_SIZE_6
                Dc.b    VIEW_PLANET10,VIEW_PAL_NoA,VIEW_FLIPPED,VIEW_SIZE_6

                
Dc.b    VIEW_PLANET4,VIEW_PAL_NoC,VIEW_FLIPPED,VIEW_SIZE_7
                Dc.b    VIEW_PLANET10,VIEW_PAL_No1,VIEW_NOT_FLIPPED,VIEW_SIZE_7