Character spins/twiches when mouse gets close

MykoNil

I am currently working on a wave survival shooter game and I came across a problem with the player's aiming. When the player aims with the mouse, the character rotates properly as seen in the picture below:

As you can see, the character rotates based on the direction from the position of the tip of the gun to the position of the mouse. It's working quite nicely. But once I aim the mouse close to the character, the character starts to twitch or spin all over the place.

I suspect it has to do with there being some kind of blind spot from the gun to the character. Since the mouse is going behind the gun, it can't point towards the mouse anymore, so it tries but just keeps spazzing out instead. I don't understand it enough and am not sure how to fix this. Here is my player code:

extends KinematicBody2D


var viewport
var screen_size
var draw_node

# Player variables
export var walk_speed = 25 #pixels per second
var mouse_position = Vector2.ZERO

var gun = null
var gun_muzzle = null




func _ready() -> void:
	screen_size = Vector2.ZERO
	viewport = get_viewport()
	screen_size = viewport.size
	draw_node = get_node("../Draw")
	
	gun = get_node("Gun")
	gun_muzzle = get_node("Gun/Position2D")
	
	set_process(true)
	


func _process(delta: float) -> void:
	var move_direction = Vector2.ZERO
	mouse_position = viewport.get_mouse_position()
	
	var look_direction = mouse_position - gun.global_position#mouse_position - position
	var look_dir_length = look_direction.length()
	look_direction = atan2(look_direction.y, look_direction.x)
	
	
	# Gets input from the player and stores the corresponding keys as integer values converted from bools
	var left_key = int(Input.is_action_pressed("move_left"))
	var right_key = int(Input.is_action_pressed("move_right"))
	var up_key = int(Input.is_action_pressed("move_up"))
	var down_key = int(Input.is_action_pressed("move_down"))
	
	var h_dir = right_key - left_key
	var v_dir = down_key - up_key
	
	# Normalize the movement vector
	move_direction = Vector2(h_dir, v_dir).normalized()
	rotation = look_direction - deg2rad(90)
	
	# Update the player's position
	position += move_direction * walk_speed * delta

	# Emit signal for drawing a line from the player to the mouse
	draw_node.emit_signal("draw_from_player_to_mouse", gun_muzzle.global_position, mouse_position)

Here is what the player's node looks like:

and the gun scene, which I make use of a Position2d node for the tip of the gun:

Thank you for your consideration!

fire7side

What I do for that is have a variable for min_look_length = some value then:

    var look_dir_length = look_direction.length()
    if look_dir_length > min_look_length:
   	 look_direction = atan2(look_direction.y, look_direction.x)

MykoNil

Thanks. This solution makes sense. Only problem is the character may not rotate when the mouse comes close. I will try exploring other options.

Lethn

@MykoNil said: Thanks. This solution makes sense. Only problem is the character may not rotate when the mouse comes close. I will try exploring other options.

There shouldn't be a need to do anything too drastic, what you should do is put the minimum distance as close to the sprite as possible. The best thing I think would be to have the look direction only happening when the mouse is practically touching the sprite, I think that would make sense for most people.

MykoNil

I'm not sure I understand what you mean in practice. The issue arose when I changed the point (from the mouse to the center of the player) to (from the mouse to the tip of the gun.) Perhaps I should keep the original point, from the origin of the player character to the mouse. Then just set the direction of the bullets from tip of the gun to the mouse.

cybereality

Yeah, for the mouse aiming to work, it has to be from the center of the sprite. Otherwise the math gets really wonky if you have 2 center points.

Lethn

Sorry I should be clear, what I mean by minimum distance is stopping the code itself from working is a good idea if you get too close to the sprite with the mouse to prevent the spinning behaviour, although there might well be a more sophisticated way of doing it.