Hey! This is absolutely awesome work! The vitaGL support is freaking awesome. Native res at 60fps is a beautiful thing to see! Shame not a lot of games actually made for the system run that way.
v2.5 is really great, but I do want to point out some issues I've found playing it for the past thirty minutes or so. I played a E1M1 of the main game and everything seems to be running pretty great. No hiccups, not even once! Underwater effects aren't working at all though, which makes some parts of levels unplayable due to the inability to navigate through the areas. There is some noticeable texture glitching in some areas, but more often than not these are repeated textures and not unique ones like for buttons or doors so it isn't too big of an issue.
Mods are still working, but the mod selection menu is not. I've noticed that the game boots a lot quicker now, so maybe it is too fast to register the R button being held to bring you into the mod menu (unless the hotkey changed; I tried a few other buttons to no avail). Editing the ux0:/data/Quake/mods.txt file with the game folder you want to launch still works okay though. I tested this with the official Hipnotic map pack. One thing I'd recommend if the mod menu isn't going to work anymore is to allow add a mod selection option to the settings menu similar to the one the DirectQ port has (pictured).
I did notice that enemies run at a significantly lower framerate than the environment, but I think that is because model interpolation is disabled. I tried enabling it through the console, but it wouldn't recommend any of my winQuake commands (unless I had the wrong ones).
One thing I would like to add that isn't a bug report but rather a feature request is the option to disable texture filtering and change the particle type from circles to squares. I tried changing the settings to allow for both via the console, but the commands weren't recognized. I know those may seem like odd requests though, but for old school Quake purists, the "crunchy" look is pretty nice to have!
EDIT: Turns out I was using the wrong commands to disable texture filtering. It is possible via the console by putting in "GL_NEAREST_MIPMAP_LINEAR"; this will make the textures appear in their raw, crunchy glory. The "r_particles 2" command is supposed to work in some engines to enable square particles, but it might not be enabled by default in QuakeGL-based engines.
This forum post has a lot of info on console commands I tried, along with some info on the other ports out there and how each one can get the retro "look" of the original DOS version of the game.
I was super stoked to see development on the port resumed! VitaGL is amazing and so is Quake, so seeing this is truly awesome! Thank you for all the effort you've put into putting this together!