69 lines
2.7 KiB
GDScript
69 lines
2.7 KiB
GDScript
extends Node2D
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@onready var up_material : ParticleProcessMaterial = load("res://Materials/Particles/up_particles.tres") #The process material for when gravity is upwards.
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@onready var down_material : ParticleProcessMaterial = load("res://Materials/Particles/down_particles.tres") #The process material for when gravity is downwards.
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@export var number_of_particles : int #The total number of particles we want emitting.
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var particle_child : GPUParticles2D #The child node that's holding the emitting particles.
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# Called when the node enters the scene tree for the first time.
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func _ready() -> void:
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#Duplicate the process materials so we have a local copy.
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#Done so we don't modify the process material attached to the player particle emitter.
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up_material = up_material.duplicate()
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down_material = down_material.duplicate()
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reloadParticles()
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func _physics_process(delta: float) -> void:
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#Run reloadParticles() when gravity is changed.
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if Input.is_action_just_pressed("flip"):
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print("input detected")
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reloadParticles()
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#Detect gravity, and set the appropriate process material to the GPUParticles2D child node.
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#If that child node does not exist, then create it, and then assign the process material.
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func reloadParticles() -> void:
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#If the particle node does not already exist, do the initial setup, and add it as a child node.
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if !has_node("BGParticles"):
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#Create a new GPUParticles2D object.
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var bgparticle := GPUParticles2D.new()
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#Set number of particles, make them emit by default, make them top level to not follow camera, and set name.
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bgparticle.amount = number_of_particles
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bgparticle.emitting = true
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bgparticle.top_level = true
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bgparticle.name = "BGParticles"
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#Add our created GPUParticles2D object as a child to this Node.
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add_child(bgparticle)
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#Set our particle_child variable equal to our newly created child Node so we can modify it later.
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particle_child = get_node_or_null("BGParticles")
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#Set up a termpoary material variable, and set up a screen size variable.
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var material : ParticleProcessMaterial
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var size : Vector2 = get_viewport_rect().size
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#Simple gravity direction detection.
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if al_globals.y_gravity > 0:
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material = up_material
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elif al_globals.y_gravity < 0:
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material = down_material
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#Set the emission shape to a box, with an assignable size.
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material.emission_shape = ParticleProcessMaterial.EMISSION_SHAPE_BOX
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#Set the bounds of the emission box equivalent to the current screen size.
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material.emission_box_extents = Vector3(size.x, size.y, 0)
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#Set the material of the particle child object to the created material.
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particle_child.process_material = material
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func _on_player_player_respawned() -> void:
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reloadParticles()
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