add projectile model and material

scripts/projectiles/projectile.gd

@@ -2,23 +2,34 @@ class_name Projectile
 extends Area3D
 
 const HEIGHT: float = 1
+const MAX_STRETCH: float = 0.75
+
+@export var _speed_stretch_factor: float = 100
 
 @export var _collision_debug_material: Material
 
 var _start_position: Vector3
 var _velocity: Vector3
 var _lifetime: float
+var _size: float = 0.25
 
 var _life_timer: float
 
 var _debug_collision_shapes := DebugCollisionShapes.new()
 
+@onready var _model_base: Node3D = $Model
+@onready var _model_mesh: MeshInstance3D = $Model/ProjectileMesh
+
 
 func _ready() -> void:
 	_life_timer = _lifetime
 	_debug_collision_shapes.init(get_children(), self, _collision_debug_material)
 	global_position = _start_position
 	body_entered.connect(_on_body_entered)
+	_model_mesh.rotation = Vector3(
+		randf_range(0, TAU), randf_range(0, TAU), randf_range(0, TAU)
+	)
+	_model_mesh.scale = Vector3.ONE * _size
 
 
 func _physics_process(delta: float) -> void:
@@ -27,6 +38,14 @@ func _physics_process(delta: float) -> void:
 
 	_life_timer -= delta
 	global_position += _velocity * delta
+	look_at(global_position + _velocity, Vector3.UP, true)
+
+	var speed_squash := clampf(
+		_velocity.length() / _speed_stretch_factor, 0, MAX_STRETCH
+	)
+	_model_base.scale = Vector3(
+		1 - speed_squash, 1 - speed_squash, 1 + speed_squash
+	)
 
 
 func init(velocity: Vector3, start_position: Vector3, lifetime: float = 10) -> void: