Game Mechanics 2D 3/4 perspective "jumping" How should I approach this?

Hello! I'm unsure if this is the correct place to post this. Please let me know if it isn't.

Basically I would like to know how one would approach putting a jumping mechanic in a game where there isn't really a "floor". Also, If were to make a 3/4 2D game, how would one go about creating platforms the player is standing on?

I thought I could just program in a curved path the player would take every time they jump but then I thought "What if they jumped off a platform that was taller than the ground? How would that work?" All I can think of is I have to put 'markers' down for every platform that I deem to be taller than the ground and adjust the jump mechanic accordingly. To me this sounds very... amateurish (which I am btw) and I feel like there's a better way to approach this. However, I'm clueless as to where I should start.

Any help would be greatly appreciated. Cheers!
 

Yal

šŸ§ *penguin noises*
GMC Elder
So your first major issue here is trying to solve a problem that uses 3D coordinates without using 3D coordinates: it's actually much easier to code threequarter/top-down jumping if you actually add a "z" variable (alongside with z speed, z gravity and so on). For the draw event, you'd draw sprites at x,y+z rather than the default, x,y. (For bonus points, use draw_sprite_ext to draw the object's sprite with 0.25 yscale, c_black blend color and 0.25 alpha at x,y - now you have a shadow under the object as well!)

Start off by just having a set Z level for the ground, you can figure out how you wanna go from there later. You might want to use an approach where rather than markers, you place props that handles drawing and Z levels instead of having separate things for everything.

Oh yeah, and a bonus of using Z coordinates is that you can just use the built-in collisions! You just need to manually check for a Z overlap (if it matters - e.g. loading zones that take you to other levels could always be active, but the player would want to jump over enemies and bullets), and if there's no overlap, you abort the event immediately.
 
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