Jim StormdancerPico-8 arranges coordinates with 0, 0 in the top left corner of the screen and y increasing as you go down. But that's a very retrocomputing-inspired design decision! Mathematicians and modern 3D engines and, like, average people looking at graphs, and even some 2D engines think 0, 0 is at the center of the screen and increasing Y means up.
My first computer was a Commodore 64, so I'm very comfortable with increasing Y meaning down. For one code base I worked on I used a graphics library that defaulted to "increasing y up" and I "fixed" it by changing the camera matrix so that increasing y was down, but that didn't fix "increasing V is up" on the texture maps so thinking about every non-trivial texture operation was a complete nightmare and now other people have to maintain that code. Sorry!
Fabian Giesen@mogwai_poet For texture maps it doesn't make a difference whether +v is up or down as long as it matches the order you upload textures in. (The only place where you can tell is render targets.)
@rygorous Yeah, I was already preprocessing the textures, I could've just flipped 'em over