Making a script to load materials based on distance to save memory?

[karmic gorge]

Here's the script I have so far

extends MeshInstance3D
class_name wc_DBML

@export_group("Setup")
@export var camera: Camera3D

@export_group("Parameters")
enum detailLevel{l1=1, l2=2, l4=4, l8=8, l16=16, l32=32, l64=64, l128=128, l256=256, l512=512, l1024=1024, l2048=2048, l4096=4096, l8192=8192}
@export var maxDetail: detailLevel = detailLevel.l1024

@export_group("Mips")
@export var mat1: Material
@export var mat2: Material
@export var mat4: Material
@export var mat8: Material
@export var mat16: Material
@export var mat32: Material
@export var mat64: Material
@export var mat128: Material
@export var mat256: Material
@export var mat512: Material
@export var mat1024: Material
@export var mat2048: Material
@export var mat4096: Material
@export var mat8192: Material

var distanceFromCamera := 0.0
var log_dfc := 0.0
var floor_dfc := 0

func setVariables() -> void:
    distanceFromCamera = getDistanceFromCamera()
    log_dfc = pow(distanceFromCamera, 0.5)
    floor_dfc = floor(log_dfc)

func _physics_process( _delta: float ) -> void:
    setVariables()
    print(maxDetail)
    updateMaterial()

func getDistanceFromCamera() -> float:
    return (global_position - camera.global_position).length()

func getMaterialToLoad() -> Material:
    match(floor_dfc):
        1:
            return mat8192
        _:
            return mat1

func updateMaterial() -> void:
    set_surface_override_material(0, getMaterialToLoad())

Simplified explanation:

This script has a bunch of @export parameters containing the materials I will use, as well as parameters such as the camera location. Then it calculates the distance between the camera and the object, and tracks that in a var called distanceFromCamera. Then it gets turned into a logarithmic curve, and then that is sent into floor() to convert it to an int. This int is then used to switch between the surface material override on surface 0.

It doesn't seem to load and unload these assets as I want them to; instead it keeps all of them loaded at all times. I want them to be unloaded and unloaded based on whenever they are needed. Is that even possible? How can I do this?

I am new to loading resources at runtime so I’m sorry if this is a dumb question.

[past ridge]

you have them in the exported variables, so that keeps them loaded

you want them gone, you have to not keep them in a variable at all, but instead keep a path and load the path manually into memory when you want to use the material.

be warned, loading is not free (fairly obvious) and if the materials are using different shaders, switching materials can cause a hitch while the shader compiles.

[karmic gorge]

Can I keep the path in a string or something?

*An exported one

[past ridge]

yeah, you can keep the path in an exported string.