KinematicBody: Stopping on Slopes
KinematicBody slides down slopes.
We’ve started with a no-frills
move_and_slide(), using the script below:
extends KinematicBody export var gravity = -10.0 export var speed = 5.0 export var rot_speed = 4.0 export var jump_speed = 5.0 var velocity = Vector3.ZERO var jumping = false func get_input(delta): var input = Vector3.ZERO if Input.is_action_pressed("forward"): input += -transform.basis.z * speed if Input.is_action_pressed("back"): input += transform.basis.z * speed if Input.is_action_pressed("right"): rotate_y(-rot_speed * delta) if Input.is_action_pressed("left"): rotate_y(rot_speed * delta) velocity.x = input.x velocity.z = input.z func _physics_process(delta): get_input(delta) velocity.y += gravity * delta velocity = move_and_slide(velocity, Vector3.UP) if jumping and is_on_floor(): jumping = false if Input.is_action_just_pressed("jump"): if is_on_floor(): jumping = true velocity.y = jump_speed
We see the problem if we stop moving on a slope:
move_and_slide() doing what it’s supposed to do.
The downward velocity caused by gravity is being slid along the surface.
move_and_slide() documentation, we see there’s a parameter called
stop_on_slope, which defaults to
stop_on_slopeis true, body will not slide on slopes when you include gravity in linear_velocity and the body is standing still.
So we can change our movement to this instead:
velocity = move_and_slide(velocity, Vector3.UP, true)
Now we stop sliding down slopes!
But there is still a problem, which is easier to see if you use a low value for
When we come to a stop, we have a little bit of upward momentum, which causes the small “hop”. We can solve this by switching to the
In order to ensure we can still jump, we also need to disable snapping during a jump, or we’ll remain “snapped” to the ground:
var snap = Vector3.DOWN if not jumping else Vector3.ZERO velocity = move_and_slide_with_snap(velocity, snap, Vector3.UP, true)
Now the “hop” is gone, and everything works as expected.
Finally, you may notice that on very steep slopes, you still have a problem:
This is because the default value of the
floor_max_angle parameter is 45°, and the slope shown is greater. Any angle above this value does not count as a floor. Increasing the value makes this slope behave like the others:
velocity = move_and_slide_with_snap(velocity, snap, Vector3.UP, true, 4, deg2rad(52))