broken_seals_roguelike/game/steering_ai_framework/Agents/GSAIKinematicBody2DAgent.gd

121 lines
3.8 KiB
GDScript

# A specialized steering agent that updates itself every frame so the user does
# not have to using a KinematicBody2D
extends GSAISpecializedAgent
class_name GSAIKinematicBody2DAgent
# SLIDE uses `move_and_slide`
# COLLIDE uses `move_and_collide`
# POSITION changes the `global_position` directly
enum MovementType { SLIDE, COLLIDE, POSITION }
# The KinematicBody2D to keep track of
var body: KinematicBody2D setget _set_body
# The type of movement the body executes
var movement_type: int
var _last_position: Vector2
func _init(_body: KinematicBody2D, _movement_type: int = MovementType.SLIDE) -> void:
if not _body.is_inside_tree():
yield(_body, "ready")
self.body = _body
self.movement_type = _movement_type
# warning-ignore:return_value_discarded
body.get_tree().connect("physics_frame", self, "_on_SceneTree_physics_frame")
# Moves the agent's `body` by target `acceleration`.
# tags: virtual
func _apply_steering(acceleration: GSAITargetAcceleration, delta: float) -> void:
_applied_steering = true
match movement_type:
MovementType.COLLIDE:
_apply_collide_steering(acceleration.linear, delta)
MovementType.SLIDE:
_apply_sliding_steering(acceleration.linear)
_:
_apply_position_steering(acceleration.linear, delta)
_apply_orientation_steering(acceleration.angular, delta)
func _apply_sliding_steering(accel: Vector3) -> void:
var velocity := GSAIUtils.to_vector2(linear_velocity + accel).clamped(linear_speed_max)
if apply_linear_drag:
velocity = velocity.linear_interpolate(Vector2.ZERO, linear_drag_percentage)
velocity = body.move_and_slide(velocity)
if calculate_velocities:
linear_velocity = GSAIUtils.to_vector3(velocity)
func _apply_collide_steering(accel: Vector3, delta: float) -> void:
var velocity := GSAIUtils.clampedv3(linear_velocity + accel, linear_speed_max)
if apply_linear_drag:
velocity = velocity.linear_interpolate(Vector3.ZERO, linear_drag_percentage)
# warning-ignore:return_value_discarded
body.move_and_collide(GSAIUtils.to_vector2(velocity) * delta)
if calculate_velocities:
linear_velocity = velocity
func _apply_position_steering(accel: Vector3, delta: float) -> void:
var velocity := GSAIUtils.clampedv3(linear_velocity + accel, linear_speed_max)
if apply_linear_drag:
velocity = velocity.linear_interpolate(Vector3.ZERO, linear_drag_percentage)
body.global_position += GSAIUtils.to_vector2(velocity) * delta
if calculate_velocities:
linear_velocity = velocity
func _apply_orientation_steering(angular_acceleration: float, delta: float) -> void:
var velocity = angular_velocity + angular_acceleration
if apply_angular_drag:
velocity = lerp(velocity, 0, angular_drag_percentage)
body.rotation += velocity * delta
if calculate_velocities:
angular_velocity = velocity
func _set_body(value: KinematicBody2D) -> void:
body = value
_last_position = body.global_position
_last_orientation = body.rotation
position = GSAIUtils.to_vector3(_last_position)
orientation = _last_orientation
func _on_SceneTree_physics_frame() -> void:
var current_position := body.global_position
var current_orientation := body.rotation
position = GSAIUtils.to_vector3(current_position)
orientation = current_orientation
if calculate_velocities:
if _applied_steering:
_applied_steering = false
else:
linear_velocity = GSAIUtils.clampedv3(
GSAIUtils.to_vector3(_last_position - current_position), linear_speed_max
)
if apply_linear_drag:
linear_velocity = linear_velocity.linear_interpolate(
Vector3.ZERO, linear_drag_percentage
)
angular_velocity = clamp(
_last_orientation - current_orientation, -angular_speed_max, angular_speed_max
)
if apply_angular_drag:
angular_velocity = lerp(angular_velocity, 0, angular_drag_percentage)
_last_position = current_position
_last_orientation = current_orientation