Recently, the "Grand Theft Auto VI: Extended Showcase" presentation took place, during which Rockstar Games demonstrated a new installment of the franchise.
Against this backdrop, Grand Theft Auto developer Mike Dailly presented his project on a social network — he assembled a remake of the first part's prototype:
There's no complex math, matrices, perspective, or anything like that used here. It's all based on a simple circle with scaling and stretching — and that's it. This prototype is a bit more advanced than the original, as you can tilt the camera and zoom — that wasn't in the old prototype.
During the discussion, Mike explained that there were originally two prototypes — a rotating one with an isometric camera, and one with a top-down view:
The one shown here [in the video] is more advanced than the first isometric prototype: you couldn't tilt the camera to look from above, it was always only from the side. The old version was just "tilted."
Mike also noted that for some time, developers tried to make an isometric GTA, but due to rendering peculiarities, "everything ran slowly," and eventually, they chose a top-down view:
A design document was even developed for [this isometric GTA prototype] — it was closer to GTA 2 with gangs, etc...
The developer published the source code of the "GTA_Prototypes" project in open access on GitHub in the mikedailly repository.