Adventure Fields had the most drastic changes in SADX. Station Square in particular had a major redesign with many new textures. The redesign itself, however, is somewhat questionable. Although it adds some shadows using vertex colors and semi-transparent models, it also loses a lot of detail, and some of the visuals are broken. Let’s compare the level side by side between Dreamcast, Gamecube and PC versions and see which one holds up better.
The area where you fight Chaos 0 was originally a red brick building with a clock tower. In SADX the clock tower was replaced with a smaller copy of the building’s lower segment. If you look closely you can see this area uses less unique textures, which are also lower quality than the original textures. Another problem with this redesign is that it creates an inconsistency with Speed Highway Act 3 because this is supposed to be the same building you enter as Knuckles or leave as Sonic in that stage. The building in Speed Highway still has the old design with the clock tower.
There were claims that SADX has “better” asphalt textures because the SADX texture is supposedly “more realistic”. Let’s have a closer look: here’s the asphalt texture from the City Hall area from both versions of the game and a quick edit to downgrade the original texture to the SADX level of quality.
One of the most serious downgrades that happened to Station Square is the window reflections. In the original game there were several reflection textures for different windows during day, evening and night, and the distortions reacted to camera movement. In SADX, most windows use the same reflection texture at all times, and the windows’ models were adjusted to make their reflections look less vibrant. The city hall area had the environment mapping effect on windows disabled entirely so the windows look completely static:
Other parts of Station Square still have the environment mapping effect, but it looks less vibrant than on the Dreamcast because of edited normals and because most windows use the same texture:
The loss of palette lighting made the level look different at night. The bluish tint is gone, and the level pieces that were lit up on the Dreamcast (such as windows) no longer change at night. The Gamecube version is darker, and the PC version looks almost the same during day and night:
Transparency effects in some areas were removed in SADX. For example, the doors and windows in this building originally had two textures to make it look like you could see what’s inside. In SADX one of the layers is no longer visible because the top texture with the environment mapping effect was made opaque. In addition, the texture on the door is messed up and fills only half the door, with the door handles moved to the top of the door.
A similar change was made to another reflection in the Casino area. You can no longer see what’s behind the glass:
The sewers area received a minor redesign. The water texture is no longer animated, its resolution wasn’t increased either, but the color was changed. The distortion effect takes care of water animation on the Gamecube, but the PC version reverts to a Dreamcast-like look which now looks awkward because the water texture isn’t animated. Some vertex colors were added to compensate for the loss of palette lighting. The lighting in the sewers changed depending on the time of day in the Dreamcast version, which didn’t make much sense. In SADX the sewers area looks the same regardless of the time of day, which is more logical.
Station Square ocean is one of the few areas in the game that use a different blending mode for the water (this mode is used only in Adventure Fields, Emerald Coast and some Chao Gardens). Some people prefer this to the low-resolution Dreamcast water texture. Others may think the SADX version looks lifeless and too “acidic”. The Gamecube version has a distortion effect, but the animated waves on the seashore are gone:
The “acidic” look of the sea is especially noticeable during the day:
The color of the sea changed depending on the time of day in the Dreamcast version. In SADX the sea ignores lighting but uses a different texture for evening. It looks a bit strange at night because the sea is lit up in the dark surroundings:
The sewers in the station area also have a different water texture. There is also some strange shadow that looks like a bug:
The glass walkway above the Twinkle Park entrance looks less colorful because the glass was redesigned to use a different model with different normals and a texture that is used on almost all glass surfaces in SADX. The environment mapping effect on the planet decoration was replaced with a solid texture, making it look like a ball. In addition, parts of the Twinkle Park entrance building no longer light up at night:
Here’s a closer look at the reflections. Note how the environment mapping effect is less vibrant on the Gamecube:
The building itself has lost transparency at the base, so the bottom of it is now solid. It’s also no longer illuminated at night:
Like the sewers, the Dreamcast version of Station Square Twinkle Park area changes lighting depending on the time of day, which doesn’t make much sense because it’s located indoors. This was changed in SADX, and now the Twinkle Park entrance always looks the same:
Similar to Speed Highway Act 3, the cars in Station Square have lost their shiny metal surface (the cars you see during the Egg Walker fight were not replaced, however). Their windows had a blue sky texture (which didn’t make sense at night) that was replaced with the familiar generic green glass texture. Some people may prefer the more detailed car textures in SADX, which supposedly makes them more “realistic”. However, the loss of the shiny metallic effect makes the car less realisitc. They now look more like plastic toys:
The police cars have lost transparency in their flashers, which not only looks less “realistic”, but also makes the inner pieces invisible. They were supposed to rotate as the car moved.
There are other minor downgrades, such as removal of transparency in pool chairs:
The windows in Tails’ upgrade section were changed to look shut, likely done to hide transparency problems:
When playing as Tails, the station doors are misplaced, which looks awkward and makes some Z fighting visible in their upper segment. This doesn’t happen in the Dreamcast version:
Another minor bug causes Sonic’s shadow to be overlapped by the crosswalk texture. Funnily enough this bug is shown off in the manual for the Gamecube version.
Another problem with the redesign involves overlapping level pieces, which create a strange looking gap near the news stand. This doesn’t happen in the original version of the level. Note how the reflection has also been toned down:
The news stand itself has suffered from texture quality degradation. The newspapers’ texture is now stretched.
The building next to the news stand was also slightly redesigned, adding new signs:
The issue with this redesign is that the “Station Square Books” sign has a low resolution texture that stands out when placed next to the sharp-looking posters:
If you look closer, you may notice that the supposed bookshop sells food!
Something similar happened to the “Urban Chillin” store in the clock tower area, where the sign was changed to “ATOZ School”, but the texture for the inside area wasn’t changed, so the “ATOZ School” appears to have clothing on display. To hide this inconsistency the window was made more opaque, but you can still see the clothes through the glass. Also note how the “ATOZ School” sign itself looks somewhat amateurish compared to the original Dreamcast sign, and it is no longer lit up at night:
The texture for the “Casino Ken” sign that was added in SADX is low resolution image, making it look particularly jarring next to the polygonal sign for the Casinopolis entrance. It’s also not centered on the actual entrance, the glass door:
One of the strangest bugs in SADX involves the hotel door, which appears to ignore lighting at all times. This happens because in SADX the lights are supposed to turn on inside the hotel when you go there at night. “Turning on the lights” involved adding an “ignore lighting” material flag to everything in the area. However, the code for turning on the lights is bugged and forces the hotel doors to ignore lighting even when you’re outside the hotel. This makes the doors look strange in the evening and at night:
Station Square has a completely different atmosphere in SADX. It also loses some texture variety, has model and lighting downgrades, missing effects, transparency issues and various visual bugs. However, this level can be reverted to the original version with the Dreamcast Conversion mod. Check out this section on how to install mods on the PC version.