change camera positioning to target-based

scripts/main_camera.gd

@@ -1,26 +1,35 @@
 extends Camera3D
 
-const MOVE_SPEED: float = 2
 const ZOOM_SPEED: float = 0.25
 ## How many pixels the mouse needs to be away
 ## from the screen edge to move the camera.
 const EDGE_THRESHOLD: float = 10
 
-@export var zoom_in_height: float = 1
+@export var zoom_in_distance: float = 1
 @export var zoom_in_fov: float = 60
 @export var zoom_in_angle: float = -0.1 * PI
+@export var zoom_in_speed: float = 2
 
-@export var zoom_out_height: float = 3
+@export var zoom_out_distance: float = 3
 @export var zoom_out_fov: float = 70
 @export var zoom_out_angle: float = -0.25 * PI
+@export var zoom_out_speed: float = 4
 
+var target_position: Vector3 = Vector3(0, 0, 0)
 var mouse_position: Vector2 = Vector2()
 ## 0 = zoomed in. 1 = zoomed out.
 var zoom_value: float = 0.25
 
 func _process(delta: float) -> void:
 	handle_movement(delta)
-	handle_zoom()
+
+	fov = lerp(zoom_in_fov, zoom_out_fov, zoom_value)
+	rotation.x = lerp(zoom_in_angle, zoom_out_angle, zoom_value)
+	var distance: float = lerp(zoom_in_distance, zoom_out_distance, zoom_value)
+
+	var offset_direction := Vector3.BACK.rotated(Vector3.RIGHT, rotation.x)
+	var offset := offset_direction * distance
+	position = target_position + offset
 
 func _input(event: InputEvent) -> void:
 	if event is InputEventMouseMotion:
@@ -61,10 +70,6 @@ func handle_movement(delta: float) -> void:
 			.rotated(Vector3.UP, rotation.y)
 	)
 
-	var velocity := direction * MOVE_SPEED
-	position += velocity * delta
-
-func handle_zoom() -> void:
-	fov = lerp(zoom_in_fov, zoom_out_fov, zoom_value)
-	rotation.x = lerp(zoom_in_angle, zoom_out_angle, zoom_value)
-	position.y = lerp(zoom_in_height, zoom_out_height, zoom_value)
+	var speed: float = lerp(zoom_in_speed, zoom_out_speed, zoom_value)
+	var velocity := direction * speed
+	target_position += velocity * delta