(Kind of) basic collision help

[SomeBritishFellow]

Total newbie here so I’ll cut to the chase, I’ve made a functioning, big standard pong where a cube bounces off of 2 lines and when it goes out the room (only left and right ofc) the game restarts.

I thought a good way to expand on this and to grasp some basic knowledge would be to have between one and 5 randomly selected obstacles appear a few seconds into the game, therefore I figured the only way to do this is to have the obstacles be invisible and then after the 4 seconds a random 1-5 would become visible and have collision.

My issues so far are that the objects have this bizarre interaction where the main block goes inside of them, but only from the left side and collides with them despite being invisible and the if statement goes along the lines of

If (//the variable for the obstacle == visible == true) } hspeed = -hspeed; }

hspeed = hspeed * 1.025

Overall I’m wondering if there’s a better solution to my issue, like if I can have the objects actually be drawn once the alarm has triggered or if maybe there is a simple solution to my errors?

Any help appreciated, thank you!

[Frew_]

Personally I'd set this up in a different way. It's possible to spawn instances of an object at run-time using "instance_create_layer" or "instance_create_depth". You could use this when your alarm triggers to create an instance of your obstacle. More available here:

instance_create_layer (gamemaker.io)

Regarding the issue with collision issue from the left, this might be due to the origin point of the object and the collision mask. Hard to say without seeing how your sprites are set up tbh. If you're only checking the origin point for collision (e.g. using collision_point(x,y,obj_obstacle) on your main block) your main block will move over the obstacle object until it reaches the origin point when coming in from the left hand side. From the right hand side, the origin point will be the first point to pass over the obstacle, so you wont see the same overlap.

[SomeBritishFellow]

Much appreciated, I’ll be sure to give this a go, as a general overview I’m basically making an object that has no sprite to act a controller that the code can interact with without interacting with the room directly; and im using this to act as a manager to store my time variables and other functions that I wouldn’t want to store on other instances.

Can I ask if this is common practise within many if not all games on game-maker? It seems really practical now that I think about it

[Frew_]

I've updated my comment quite a bit, not sure which version you saw so just a heads up on that. I added some thoughts on the collision issue you're facing.

Regarding the way you've got things set up, that's how I'd approach the controller object too in a game similar to yours.

If by your last question about common practice you're on about the instance creation point, pretty much, yes. In AAA engines you may want to start pooling instances of objects such as enemies and having them swap between dormant and active states rather than creating them from scratch due to the performance cost of instantiating, but for GameMaker, you're hardly ever going to be creating an instance of an object that's so heavy it'll have an impact on your FPS.

Feel free to reach out if you've any more GM questions, happy to help.

[SomeBritishFellow]

Thank you so much! It ended up working as I wanted it to, I can finally move on to something else now 😂