Consider using Framebuffer::GFX and Adafruit's NeoMatrix Mapping for 2D support

[marcmerlin]

I can't re-open https://github.com/Aircoookie/WLED/issues/2197 but in the last 3 years since I opened it, I've heard of more peole using wled and now trying to do 2D with it, which it wasn't originally built to do.

as discussed on https://www.facebook.com/groups/LEDSAREAWESOME/posts/2360328277495951/?comment_id=2362375507291228&reply_comment_id=2363141040548008&notif_id=1713103541286836&notif_t=group_comment_mention
I pointed out that adafruit's mapping work is both super important and useful when you chain matrices as getting coordinate right, is non trivial:

Maybe it would be a good time to re-visit looking at

• http://marc.merlins.org/perso/arduino/post_2020-03-16_Framebuffer_GFX_-Choosing-between-its-3-2D-APIs_-FastLED-XY_-NeoMatrix_-and-LEDMatrix_-and-detail-of-its-many-supported-hardware-backends.html
• https://github.com/marcmerlin/Framebuffer_GFX and especially
• https://github.com/marcmerlin/FastLED_NeoMatrix (which is built on top of framebuffer::GFX)

top easily add 2D framebuffer support that will work with all kinds of hardware, support the weird Z mappings of chained panels, and allow using code that uses FastLED, Adafruit::GFX, and LEDMatrix primitives and APIs. All this stuff is already written and already exists, might as well re-use it :)