Another thing I’ve been working on lately is two types of objects which can be linked to stage elements, such as a moving platform. One object detects when a nearby light source is casting light on it, and the other detects when a shadow is being cast on it. Stage elements can have multiple or a combination of these linked to require activation. Light can be blocked (and similarly, shadows cast) by Luna, ground/walls, platforms, and anything else I need to add for level design purposes.

These ended up much more complicated to get working than I had originally anticipated… and also learned more than I expected about collision detection in GMS. (Who knew that “compatibility mode” for older projects means the bottom and right edges of the collision mask aren’t used for collision detection…) I think each one went through at least three iterations. The methods I landed on work pretty well and can be tweaked more easily than what I started with though.