[Feature Request] Chance for VT03/VT09 support?

[oshaboy]

Probably Never going to happen but still worth asking. Mostly for Explorer (Decent Galaxian clone with enhanced VT03 graphics) and JonTron Jokes.

Also support for .wxn format.

[SourMesen]

Thanks for the request.

VT0x support would be nice to have, but the VT0x are so different from a standard NES that it gets a bit tricky to implement them while keeping the code clean and without negatively affecting performance. They also open up a bunch of potential issues (e.g all the debug tools relating to the PPU would probably be half broken when using VT0x games, etc.)

That being said, I'm not saying "no, never", but I'm not familiar enough with the exact VT0x specs to know how complex it would be to integrate support for it cleanly. And with much of my time spent on Mesen-S lately and some other priorities on the Mesen side of things (e.g adding support for some of the missing peripherals, or mappers like the study box, etc.), it will probably be a long time until I can find the time to look into this.

[oshaboy]

Oh, I thought VT03 was just an extra video mode. I didn't think it was so different. Especially because I could get the games running sans graphics by just messing with the header. I can even play Hitting Mices because in that game objects are glitched into stripy rectangles.

[SourMesen]

There's a fairly thorough list of differences for each model here: https://wiki.nesdev.com/w/index.php/VTxx My understanding is that the VT09, for example, is everything the VT03 + the stuff listed under VT09, etc.

The fact that the system allows things like sprites that aren't sizes that the NES supports or supports a lot more color than the NES has a lot of repercussions on the code, since these aren't the type of things a regular NES could ever do, even if you added a pretty advanced chip in the cartridge itself.