It's great to see something similar on the effects used in driving games, which I always imagined to be akin to raycasting's vertical slices drawn horizontally.
https://en.wikipedia.org/wiki/Mode_7
The article mentions about halfway down the page that what made the 80s road rendering technique possible was racing the beam. Where say an Atari 2600 would toggle the color at certain pixel counts as the TV's electron beam swept the screen, producing graphics that seemed otherwise impossible from such underpowered hardware:
https://en.wikipedia.org/wiki/Racing_the_Beam
https://www.youtube.com/watch?v=sJFnWZH5FXc
Some engines allowed for say 8 hardcoded sprites this way by toggling colors at each sprite's position, with various rules about overlapping, so sprites would flicker sometimes when they were next to each other.
2016 (115 points, 12 comments) https://news.ycombinator.com/item?id=14017574
2015 (148 points, 26 comments) https://news.ycombinator.com/item?id=8847063
Here's an example from the early 90s in a PC DOS game (Word Rally Fever, heavily inspired by Power Drift):
FWIW it was made by friends of mine, got published by Team 17, and I was a beta-tester of that one :)
Mode 7 on the SNES was usually fine. I don't know how accurately it rendered a single flat surface in 3D, but it felt real enough and responsive enough. Except for the very rare cases where they simulated non-flat surfaces (Speed Racer, Super Off-Road), even though that was technically much more impressive.
The effect just didn't work for me - it didn't feel like turning, it just felt like what it was: The game displaying a "left turn" animation and telling you that your car will now start drifting to the right if you don't press left. And that felt more like playing a Game&Watch toy.
But most games that implemented this technique were much more primitive, and just amounted to "bending" the road to indicate turns, which never feels like there's actually a turn coming towards you. It just feels like the road is suddenly changing its shape. But that's not an inherent fault of the technique, it's just a poor implementation.
I do agree that Mode7 games, which effectively display an almost correctly rendered 3D plane, are generally a much better experience.
After looking at a couple videos, I think the "secret sauce" was having objects along the sides of the road to reinforce the illusion of movement. Even in OutRun, sequences where the player drives past objects like trees or road signs feel more convincing than ones in open areas.
It's not a good feeling as a player when a game mostly plays itself and gives you some token involvement.
Also, the patched Road Rash 1-2-3 ROMs for the Mega Drive run much better with far more frames, and neither any overclocking is required at all, nor any extra hardware. That make them very good on simulating pseudo-3D races.
My personal opinion is that to qualify as 2.5D the game engine must internally use a 3D coordinate system even if the render process is 2D, and 3D requires a true 3D to 3D conversion.
