Execution

Frequency of calling ' _physics_process() ' and its execution order

  • NCarter: "Everything is called in sequence, it'll never run two process-type functions simultaneously.

  • The way _physics_process()  works is that the engine looks at how long the last frame worked and then runs a loop which calls _physics_process()  as many times as is necessary to compensate.

  • Normally your vsynced frame rate would be 60Hz and the default _physics_process()  rate is also 60Hz, so you just get one _physics_process()  per frame. If you're actually running at 120Hz, you'll get two _physics_process()  calls per frame (for each object). If you're running at 45Hz or something, you'll get a mixture of one and zero _physics_process()  calls per frame. Like I say, these are called in a loop, so you get _process  once per frame and zero or more _physics_process()  calls one after another in the same frame. It doesn't do anything fancy like try to space out the _physics_process()  calls so that they are called at regular intervals in real time, so there is no way they can overlap each other for that reason. I think there's something in there to deal with snowballing _physics_process()  cost, which would happen if _physics_process()  is taking so much time up that it makes the frame take longer, and then even more _physics_process()  calls are needed on the next frame. I think it has a maximum number of calls it will make in a single frame, and the consequence will be that the action slows down; it's that, or if the _physics_process()  takes too long to call, then it stops rendering to catch up."

Execution time

  • .

Notifications

Execution order

'set_deferred' and 'call_deferred' (Delay a task until the next frame)

  • call_deferred, yield & Threads .

  • set_deferred  is used to change a property. Only 1 parameter can be passed.

    • hitbox.set_deferred("disabled", true)

  • call_deferred  ("callable deferred") is used to call a 'callable' (function/method). Multiple parameters can be passed according to the number expected by the function/method.

    • hitbox.call_deferred("explode_hitbox", 'hell yeah!', true)

  • A 'queue' is made before executing the task, waiting for the next frame to run it. This is important when altering a physics process of the engine or doing something extreme to a node.

    • Some examples where it might be important to use one of these methods:

      • queue_free() ;

      • Changing the shape of CollisionShapes2D or CollisionPolygons2D;

      • Toggle 'Monitoring', 'Monitorable', Layers, and Collision Masks.

Await

  • Documentation .

  • Create a timer in the script.

  • Use await  by creating a Timer and waiting for its 'timeout' Signal:

    • This method creates a 'temporary Timer' at the top of the SceneTree containing this Node, while waiting for the 'timeout' Signal to indicate the Timer has ended, allowing the Script to continue from the await . The 'temporary Timer' created by .create_timer()  can only exist at the top of a SceneTree and is deleted automatically when its time ends.

    • The create_timer  time is given in seconds.

    • await get_tree().create_timer(0.2).timeout

  • Use await  with an existing node while waiting for its Signal. 

$AniPlayer.play('animation')
await $AniPlayer.animation_finished

  • Note: Timers created in the SceneTree  cannot be paused unless parameters of the .create_timer()  call are changed.