How to track touchscreen drag events more fluently?

NONAME_STUDIO

I'm using _input() to process screen drag events in my game.
But it can't catch every movement of my finger,especially when I move very fast.
I think there is a delay between touch detections.
I would like to know how to remove the delay. (just as fast as the game runs,90fps maybe enough)😄

xyz

NONAME_STUDIO Are you updating in _process() or _physics_process()?

NONAME_STUDIO

xyz
I just used the default _input() function.
Is it possible to update every frame?

xyz

NONAME_STUDIO You do everything in _input()? No process functions exist in your project? In that case you're likely running as os is supplying the events. You can measure how often it's getting called by printing the current time in milliseconds from within the function.

If you're updating any physics object from _input() they'll only be updated as fast as the physics engine ticks, which may be slower than event frequency and slower than frame rate.

So it's bound to two things: what you're actually updating in the engine and os input latency.

Maybe make a minimal code example and post it.

NONAME_STUDIO

xyz
I just judged the drag direction,if it's within 45,135,then I move the sprite up,etc.
It made no response when dragging very fast.

kuligs2

xyz how would you debug the mrp on a device that dont have touchscreen?

xyz

NONAME_STUDIO Post some code.

xyz

kuligs2 I haven't said mrp. I said code example, to see what and how is getting updated.

NONAME_STUDIO

xyz
Just a simple code.
extends Sprite2D func _input(event: InputEvent) -> void: if event is InputEventScreenDrag: event=event as InputEventScreenDrag var input_dir:float=fmod(rad_to_deg(event.velocity.angle())+360,360) assert(input_dir>=0) if input_dir>=45 and input_dir<=135: global_position.y+=30 if input_dir>=135 and input_dir<=225: global_position.x-=30 if input_dir>=315 or input_dir<=45: global_position.x+=30 if input_dir>=225 and input_dir<=315: global_position.x-=30

xyz

NONAME_STUDIO Why 30? What's the magic of 30?

If you want the sprite to be where the drag is, directly assign event's position property to sprite's global_position property.

If you want to constrain it to only 4 directions, take x and y from event's relative and add the one that has bigger absolute value to the corresponding global_position component of the sprite.

NONAME_STUDIO

xyz
I didn't want the sprite to be actually where the drag is .
I just need to know which direction the user has dragged to.
There are hundreds of nodes in my game, and every one would judge drag direction like that.
Different nodes would behave differently based on the drag direction.

xyz

NONAME_STUDIO I didn't want the sprite to be actually where the drag is .

How do you know there's delay then? Delay between what and what?

If you have hundreds of nodes running this script simultaneously your framerate could suffer. Assign str(Engine.get_frames_per_second()) to some debug label each frame, to monitor what's happening with fps at runtime.

Btw moving stuff like this is not really a wise idea because the movement speed in your code will be framerate dependent. Look up how to do framerate independent movement.

All in all, the events probably fire just fine. It's what your code does with them that's likely a problem.

NONAME_STUDIO

xyz
Sometimes I dragged but none of the nodes made response.
So I guess there is a delay in the engine between two event checks.
The frame rate was 80 on my phone,90 on my laptop.

xyz

NONAME_STUDIO What are you trying to accomplish with this movement? What type of game is this?

NONAME_STUDIO

A music game powered by AI.
I trained a pytorch model to generate charts.
The player needs to drag with the beats.

xyz

NONAME_STUDIO Post a video example of what you're trying to do.

NONAME_STUDIO

xyz
The video is too large to upload.
But I can show an image

It's a game inspired by phigros.

xyz

NONAME_STUDIO This image doesn't really explain anything.

DaveTheCoder

NONAME_STUDIO The video is too large to upload.

If you can access Youtube, it's a relatively convenient way to post videos.

NONAME_STUDIO

DaveTheCoder
Unfortunately,I'm in China without VPN.
No YouTube.

kuligs2

NONAME_STUDIO if youre in china how can you access this website? Anything outside china firewall is considered highly illegal.

20 social credits has been deducted.

xyz

NONAME_STUDIO You can try using the same code for mouse movement event on laptop instead. If it still behaves the same, that's a confirmation that the problem is in what your code does, not the event latency itself.

Tomcat

NONAME_STUDIO Unfortunately,I'm in China without VPN.
No YouTube.

Does Streamable work for you? Someone posted a video from a Chinese hosting site here. It seemed to work.

kuligs2 if youre in china how can you access this website? Anything outside china firewall is considered highly illegal.

20 social credits has been deducted.

Where do you get this nonsense? Not everything in China is blocked from the outside world.