godot-steering-ai-framework/project/src/Agents/GSTKinematicBody2DAgent.gd
2020-02-06 16:30:53 -05:00

139 lines
3.9 KiB
GDScript

# A specialized steering agent that updates itself every frame so the user does
# not have to using a KinematicBody2D
extends GSTSpecializedAgent
class_name GSTKinematicBody2DAgent
enum KinematicMovementType { SLIDE, COLLIDE, POSITION }
# The KinematicBody2D to keep track of
var body: KinematicBody2D setget _set_body
# The type of movement the body executes
#
# SLIDE uses use move_and_slide
# COLLIDE uses move_and_collide
# POSITION changes the global_position directly
var kinematic_movement_type: int = KinematicMovementType.SLIDE
var _last_position: Vector2
func _init(body: KinematicBody2D) -> void:
self.body = body
if body.is_inside_tree():
body.get_tree().connect("physics_frame", self, "_on_SceneTree_frame")
else:
body.connect("ready", self, "_on_body_ready")
# Moves the agent's `body` by target `acceleration`.
# tags: virtual
func _apply_steering(acceleration: GSTTargetAcceleration, delta: float) -> void:
_applied_steering = true
match kinematic_movement_type:
KinematicMovementType.COLLIDE:
_apply_collide_steering(acceleration.linear, delta)
KinematicMovementType.SLIDE:
_apply_sliding_steering(acceleration.linear)
_:
_apply_normal_steering(acceleration.linear, delta)
_apply_orientation_steering(acceleration.angular, delta)
func _apply_sliding_steering(accel: Vector3) -> void:
var velocity := GSTUtils.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 = GSTUtils.to_vector3(velocity)
func _apply_collide_steering(accel: Vector3, delta: float) -> void:
var velocity := GSTUtils.clampedv3(linear_velocity + accel, linear_speed_max)
if apply_linear_drag:
velocity = velocity.linear_interpolate(
Vector3.ZERO,
linear_drag_percentage
)
body.move_and_collide(GSTUtils.to_vector2(velocity) * delta)
if calculate_velocities:
linear_velocity = velocity
func _apply_normal_steering(accel: Vector3, delta: float) -> void:
var velocity := GSTUtils.clampedv3(linear_velocity + accel, linear_speed_max)
if apply_linear_drag:
velocity = velocity.linear_interpolate(
Vector3.ZERO,
linear_drag_percentage
)
body.global_position += GSTUtils.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 = GSTUtils.to_vector3(_last_position)
orientation = _last_orientation
func _on_body_ready() -> void:
body.get_tree().connect("physics_frame", self, "_on_SceneTree_frame")
_set_body(body)
func _on_SceneTree_frame() -> void:
var current_position: Vector2 = body.global_position
var current_orientation: float = body.rotation
position = GSTUtils.to_vector3(current_position)
orientation = current_orientation
if calculate_velocities:
if _applied_steering:
_applied_steering = false
else:
linear_velocity = GSTUtils.clampedv3(
GSTUtils.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