Files
CosmicClash/Game/scripts/ship_camera.gd
T

108 lines
3.8 KiB
GDScript

class_name ShipCameraRig
extends Node3D
# Third-person camera for a Ship. Ball Cam keeps the ship between the camera
# and the ball; Ship Cam chases behind the ship. The game mode spawns this
# rig and assigns `target` after spawning the player's ship — ships
# themselves are camera-free (a headless/AI ship never needs one).
signal camera_mode_changed(is_ball_cam: bool)
@export var camera_distance := 8.0
@export var camera_height := 4.0
@export var camera_smoothing := 10.0
var target: Ship
var ball_cam_enabled := true
@onready var camera: Camera3D = $Camera3D
var _ball: Node3D
func _ready():
# Group lets the HUD discover the rig for the camera-mode instrument
add_to_group("ship_camera")
func _input(event):
if event.is_action_pressed("ui_accept"): # Enter key
ball_cam_enabled = !ball_cam_enabled
camera_mode_changed.emit(ball_cam_enabled)
func _physics_process(delta):
if not is_instance_valid(target):
return
var ball := _get_ball()
if ball_cam_enabled and ball:
_update_ball_cam(delta, ball)
else:
_update_ship_cam(delta)
func _get_ball() -> Node3D:
if not is_instance_valid(_ball):
_ball = get_tree().get_first_node_in_group("ball")
return _ball
func _update_ball_cam(delta, ball: Node3D):
# In ball cam, camera positions itself so the ship is between camera and ball
# Physics: Vector mathematics for 3D positioning
var ship_pos = target.global_transform.origin
var ball_pos = ball.global_transform.origin
# Calculate direction from ball to ship
# Physics: Vector subtraction and normalization
# Direction vector: d̂ = (P₂ - P₁) / |P₂ - P₁|
var ball_to_ship = (ship_pos - ball_pos).normalized()
# Position camera behind the ship relative to the ball's position
# This ensures the ship is always between the camera and ball
# Physics: Vector addition for position calculation
# P_camera = P_ship + d̂ * distance + height_offset
var camera_target_pos = ship_pos + ball_to_ship * camera_distance + Vector3.UP * camera_height
# Smoothly move camera to target position
# Physics: Linear interpolation (LERP) for smooth motion
# P(t) = P₀ + t * (P₁ - P₀), where t ∈ [0,1]
# This creates exponential approach to target position
camera.global_transform.origin = camera.global_transform.origin.lerp(camera_target_pos, camera_smoothing * delta)
# Make camera look at the ball
if camera.global_transform.origin.distance_to(ball_pos) > 0.1:
# Calculate direction to ball
var camera_pos = camera.global_transform.origin
var to_ball = (ball_pos - camera_pos).normalized()
# Create look-at transform manually
# Physics: 3D rotation matrices and basis vectors
# Uses right-hand rule: forward = -Z, up = Y, right = X
# Basis matrix transforms local coordinates to world coordinates
var camera_transform = Transform3D()
camera_transform.origin = camera_pos
camera_transform.basis = Basis.looking_at(to_ball, Vector3.UP)
# Apply the rotation smoothly
# Physics: Spherical linear interpolation (SLERP) for rotation
# SLERP provides smooth rotation along great circle on unit sphere
# Maintains constant angular velocity during interpolation
camera.global_transform.basis = camera.global_transform.basis.slerp(camera_transform.basis, camera_smoothing * delta)
func _update_ship_cam(delta):
# In ship cam, camera follows and looks in the same direction as the ship
var ship_pos = target.global_transform.origin
var ship_forward = -target.global_transform.basis.z
# Position camera behind and above the ship
var camera_target_pos = ship_pos - ship_forward * camera_distance + Vector3.UP * camera_height
# Smoothly move camera
camera.global_transform.origin = camera.global_transform.origin.lerp(camera_target_pos, camera_smoothing * delta)
# Make camera look in the same direction as the ship
var look_target = ship_pos + ship_forward * 10.0 # Look ahead of the ship
camera.look_at(look_target, Vector3.UP)