I haven't played the original, but I have played the PS1 version with the 3d planet. Pretty strange game tbh, but I did get a taste for the "little planet" style.

If you didn't understand the jargon, what I'm doing in layman's terms is using a mathematical formula to assign (X,Y) cell coordinates to a unique number that is used to look up that cell later. If the the formula is bad, then separate coordinates can lead to the same number, causing errors!

Thank you!!

One time at programming class in community college, there was this dude who kept bringing his knitting stuff to knit random stuff and everyone was into it

I appreciate all the help! For now though, considering this problem solved on account of the fact the game is even more performant than before the lighting layer was even added.

I'm not sure about any garbage collection either. As far as I can tell, I'm setting elements in the array, which doesn't change size, then reading them each frame. The array should only be getting gc'd when the game transitions away from the world map and deletes the shade layer instance.

Do you mean I should create structs that contain the 7 sprite-drawing datapoints as members instead of it being a second array dimension?

From what I understand a set is unordered and good for search, whereas I need the elements in order so they can be drawn back to front.
It's a 2d array where the first dimension is the draw order, and the second contains the necessary drawing data in 7 elements. Not even sure I have sets in GML...

Currently the sprite data is conveyed using a queue datastructure, but since there's a set number of tiles at any given time, a simpler array solution should do the trick, and save frames!!

The tile has to draw its graphics a second time onto the shading layer each frame. BUT switching drawing surfaces multiple times a frame is slow!!!! Sooo, I have to record the data for what sprites are drawn where for the shading, THEN blast them all in a row after switching to the shade layer ONCE

You'd think just the buildings would need a mask, but every graphic on every tile has to be a part of the masking so that they can obscure lighting rendered behind them.

The tricky thing about the new lighting layer is achieving the glow effect for individual building sprites. They each have a light-mask layer to achieve this, which is drawn onto the shading layer, which is in turn drawn on top of the worl map.