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Super Mario Kart was clearly designed with multiplayer in mind, and rightfully so – with two players, it's one of the most compelling experiences on the SNES.
The focus on two human players competing with one another shows in the fact that, even when playing solo, you never get the full-screen experience; the upper section is reserved for the map.
Over time, fans of the game have come to accept that this is the natural order of things with the seminal 16-bit, Mode 7 racer – but hacker Psicopompo has 'fixed' it with a new patch.
"Super Mario Kart – Fullscreen Edition transforms the 1-player race view into a true fullscreen experience, using the entire 256×224 display area instead of reserving the lower portion for the map and rear-view mirror," explains the developer.
"This is not simply a matter of hiding the lower screen or moving Mario downward. The camera reference has been changed, bringing the projected scenery closer to the kart while keeping the kart itself in its new screen position. The game’s projection, object placement, collisions, effects, HUD, and numerous other systems have been adapted to work correctly with the new perspective.
So what changes? Well, at the start of each race, the camera "progressively moves into its new position instead of switching instantly," says Psicopompo, before adding:
"The kart remains in its new screen position while the projected scenery moves toward it, similar to the visual effect produced when accelerating in the original game. This brings the starting grid, rivals, and road back into the correct relationship with the player while making use of the full 224-line display."
The "underlying Mode 7 projection" has been adjusted to account for this, so the road, shadows, rivals, objects, and collision checks "remain consistent with the new camera reference."
Psicopompo adds:
"The HUD has also been redesigned for the additional space. Position digits, coins, car counters, LAP TIME, standings faces, and several end-of-race and status messages have been repositioned to fit the new layout. A number of effects that were tied to the original player position — including lost coins, bananas, crush smoke, and Monty Moles — were likewise adapted. Lakitu’s rescue after falling off the track also works in fullscreen: he comes into view, picks up the kart with the coin, and lifts it back onto the track, as in the original game."
As you can appreciate, this wasn't an easy process. "The final result is much more than a graphical layout change," says Psicopompo. "It is a substantial reworking of the game’s 1-player camera, presentation, and the logic that supports the new viewpoint. The development relied heavily on reproducible emulator states, instrumentation, regression testing, and frame-by-frame comparisons to ensure that fixes did not introduce new problems."
You can grab the patch file here.