thewheelbarrow/3d-car-game
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

changed to use max static friction

Browse Source
This commit is contained in:
Wheelbarrow
2025-07-26 15:29:11 -04:00
parent 15547fce8d
commit c1426ddcc0
2 changed files with 36 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
car.gd
View File

@@ -53,7 +53,7 @@ func steer(delta: float) -> void:
front_left.rotation.y = -outer_angle front_left.rotation.y = -outer_angle
func apply_air_resistance() -> void: func apply_air_resistance() -> void:
var force: Vector3 = air_resistance * linear_velocity * linear_velocity.length() var force: Vector3 = -air_resistance * linear_velocity * linear_velocity.length()
apply_force(force, center_of_mass) apply_force(force, center_of_mass)
DebugDraw3D.draw_arrow( DebugDraw3D.draw_arrow(
to_global(center_of_mass), to_global(center_of_mass),

43
wheel.gd
View File

@@ -9,25 +9,31 @@ extends RayCast3D
@export var suspension_rest_length: float = 0.1 @export var suspension_rest_length: float = 0.1
@export var suspension_stiffness: float = 30_000 @export var suspension_stiffness: float = 30_000
@export var suspension_damping: float = 2000 @export var suspension_damping: float = 2000
@export_group("Friction")
@export var static_friction: float = 1.1
var car: Car var car: Car
var acceleration: Vector3
var _last_velocity: Vector3 var _last_velocity: Vector3
func _ready() -> void: func _ready() -> void:
target_position *= suspension_rest_length + wheel_radius target_position *= suspension_rest_length + wheel_radius
$"RX-Wheel".rotate_y(PI if flipped else 0.0) if flipped: $"RX-Wheel".rotate_y(PI)
func set_new_car(new_car: Car) -> void: func set_new_car(new_car: Car) -> void:
car = new_car car = new_car
# Little bit freaky but we put up with it # Little bit freaky but we put up with it
_last_velocity = car.get_velocity_at_point(get_collision_point()) _last_velocity = car.get_velocity_at_point(get_collision_point())
func _physics_process(_delta: float) -> void: func _physics_process(delta: float) -> void:
var velocity: Vector3 = car.get_velocity_at_point(get_collision_point())
acceleration = velocity - _last_velocity / delta
force_raycast_update() force_raycast_update()
apply_suspension_force() apply_suspension_force()
apply_rolling_resistance() apply_rolling_resistance()
apply_engine_force() apply_friction_force()
_last_velocity = car.get_velocity_at_point(get_collision_point()) _last_velocity = car.get_velocity_at_point(get_collision_point())
func apply_suspension_force() -> void: func apply_suspension_force() -> void:
@@ -71,25 +77,46 @@ func apply_rolling_resistance() -> void:
car.apply_force(force, car.to_local(get_collision_point())) car.apply_force(force, car.to_local(get_collision_point()))
DebugDraw3D.draw_arrow( DebugDraw3D.draw_arrow(
arrow_tail, arrow_tail,
arrow_tail + force, arrow_tail + force / 250,
Color.ORANGE, Color.ORANGE,
.2 .2
) )
func apply_engine_force() -> void: func apply_friction_force() -> void:
if not on_drivetrain: return if not on_drivetrain: return
if not is_colliding(): return if not is_colliding(): return
var forwards: Vector3 = -global_basis.z var forwards: Vector3 = -global_basis.z
var backwards: Vector3 = global_basis.z
var normal: Vector3 = get_collision_normal()
var total_weight: Vector3 = car.mass * car.get_gravity()
var wheel_to_com: float = abs(
forwards.dot(car.center_of_mass) - \
forwards.dot(car.to_local(get_collision_point()))
)
var weight: Vector3 = wheel_to_com / car.wheelbase * total_weight
var normal_force: Vector3 = -weight
# Intern please fix
var surface_static_friction: float = 1
var static_friction_coeff: float = static_friction * surface_static_friction
var maximum_static_friction: float = static_friction_coeff * normal_force.length()
var torque: float = car.get_torque_per_wheel() var torque: float = car.get_torque_per_wheel()
var force: Vector3 = forwards * torque / wheel_radius var applied_force: Vector3 = backwards * torque / wheel_radius
#Restricts applied force to plane parralel to surface
applied_force -= normal * applied_force.dot(normal)
var friction_force: Vector3 = Vector3.ZERO
if applied_force.length() <= maximum_static_friction:
friction_force = -applied_force
var arrow_tail: Vector3 = to_global(get_wheel_center()) var arrow_tail: Vector3 = to_global(get_wheel_center())
car.apply_force(force, car.to_local(get_collision_point())) car.apply_force(friction_force, car.to_local(get_collision_point()))
DebugDraw3D.draw_arrow( DebugDraw3D.draw_arrow(
arrow_tail, arrow_tail,
arrow_tail + force / 250, arrow_tail + friction_force / 250,
Color.BLUE, Color.BLUE,
.2 .2
) )