切换玩家时空中角色冻结，如何使其受物理影响下落？

当原操控角色处于空中时进行玩家切换，该角色会冻结在当前位置。需要实现切换玩家后，原操控角色能够遵循物理规律下落至地面。

角色控制代码 #

extends CharacterBody3D
@onready var camera_mount = $camera_mount
@onready var animation_player = $visuals/mixamo_base/AnimationPlayer
@onready var visuals = $visuals
@onready var camera_3d = $camera_mount/Camera3D

@export var is_current:bool = true
@export var is_main = true
@export var SPEED = 5.0
@export var JUMP_VELOCITY = 4.5
@export var SENSIVITY = 0.05
var walk_speed = 3.0
var run_speed = 5.0
var is_running = false
var gravity = ProjectSettings.get_setting("physics/3d/default_gravity")

func _ready() -> void:
    if is_main:
        Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)

func _input(event):
    if is_main:
        if event is InputEventMouseMotion:
            rotate_y(deg_to_rad(-event.relative.x*SENSIVITY))
            visuals.rotate_y(deg_to_rad(event.relative.x*SENSIVITY))
            camera_mount.rotate_x(deg_to_rad(-event.relative.y*SENSIVITY))
            

    
func _physics_process(delta):
    if is_main:
        camera_3d.current = is_current

        if not is_on_floor():
            velocity.y -= gravity * delta
        if Input.is_action_pressed("run"):
            SPEED = run_speed
            is_running = true
        else:
            is_running = false
            SPEED = walk_speed
            

        if Input.is_action_just_pressed("ui_accept") and is_on_floor():
            velocity.y = JUMP_VELOCITY
            
        if Input.is_action_just_pressed("ui_cancel"):
            Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)


        var input_dir = Input.get_vector("move_left", "move_right", "move_forward", "move_back")
        
        var direction = (transform.basis * Vector3(input_dir.x, 0, input_dir.y)).normalized()
        if direction:
            if animation_player.current_animation != "walking" && is_running == false:
                animation_player.play("walking")
                
            if animation_player.current_animation != "running" && is_running:
                animation_player.play("running")
            
                
            visuals.look_at(position+direction)
                
            velocity.x = direction.x * SPEED
            velocity.z = direction.z * SPEED
        else:
            if animation_player.current_animation != "idle":
                animation_player.play("idle")
                
            velocity.x = move_toward(velocity.x, 0, SPEED)
            velocity.z = move_toward(velocity.z, 0, SPEED)
            
        camera_mount.rotation.x = clamp(camera_mount.rotation.x, 
            deg_to_rad(-90), 
            deg_to_rad(70)
        )

        move_and_slide()

玩家切换脚本 #

extends Node3D

@onready var player_1 = $"../Player1"
@onready var player_2 = $"../Player2"

func _physics_process(_delta):
    if Input.is_action_just_pressed("switch_player"):
        if player_1.is_main:
            player_1.is_main = false
            player_2.is_main = true
            player_2.is_current = true
            player_1.animation_player.play("idle")
        else:
            player_1.is_main = true
            player_2.is_main = false
            player_1.is_current = true
            player_2.animation_player.play("idle")

解决方案 #

问题根源 #

角色控制代码中，_physics_process内的所有物理逻辑（重力应用、move_and_slide执行）都被包裹在if is_main:判断中。当切换玩家后，原角色的is_main变为false，这些物理逻辑不再执行，导致角色冻结在空中。

修改步骤 #

1. 调整角色控制代码的物理逻辑

将重力应用和move_and_slide移出if is_main:判断，让所有角色（无论是否为主角色）都能处理物理下落和移动。修改后的_physics_process函数如下：

func _physics_process(delta):
    # 所有角色都执行物理下落逻辑
    if not is_on_floor():
        velocity.y -= gravity * delta
    
    if is_main:
        camera_3d.current = is_current

        if Input.is_action_pressed("run"):
            SPEED = run_speed
            is_running = true
        else:
            is_running = false
            SPEED = walk_speed

        if Input.is_action_just_pressed("ui_accept") and is_on_floor():
            velocity.y = JUMP_VELOCITY
            
        if Input.is_action_just_pressed("ui_cancel"):
            Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)

        var input_dir = Input.get_vector("move_left", "move_right", "move_forward", "move_back")
        
        var direction = (transform.basis * Vector3(input_dir.x, 0, input_dir.y)).normalized()
        if direction:
            if animation_player.current_animation != "walking" && is_running == false:
                animation_player.play("walking")
                
            if animation_player.current_animation != "running" && is_running:
                animation_player.play("running")
            
            visuals.look_at(position+direction)
                
            velocity.x = direction.x * SPEED
            velocity.z = direction.z * SPEED
        else:
            if animation_player.current_animation != "idle":
                animation_player.play("idle")
                
            velocity.x = move_toward(velocity.x, 0, SPEED)
            velocity.z = move_toward(velocity.z, 0, SPEED)
            
        camera_mount.rotation.x = clamp(camera_mount.rotation.x, 
            deg_to_rad(-90), 
            deg_to_rad(70)
        )
    
    # 所有角色都执行移动更新
    move_and_slide()

2. 优化切换脚本的动画逻辑（可选）

切换玩家时，根据原角色是否在地面，播放对应的动画（如果有下落动画的话），让表现更自然：

extends Node3D

@onready var player_1 = $"../Player1"
@onready var player_2 = $"../Player2"

func _physics_process(_delta):
    if Input.is_action_just_pressed("switch_player"):
        if player_1.is_main:
            player_1.is_main = false
            player_2.is_main = true
            player_2.is_current = true
            # 空中角色播放下落动画，地面角色播放idle
            if not player_1.is_on_floor():
                player_1.animation_player.play("falling")
            else:
                player_1.animation_player.play("idle")
        else:
            player_1.is_main = true
            player_2.is_main = false
            player_1.is_current = true
            if not player_2.is_on_floor():
                player_2.animation_player.play("falling")
            else:
                player_2.animation_player.play("idle")

修改完成后，切换玩家时，空中的原角色会继续受到重力影响，自然下落至地面，同时保持正确的动画状态。

内容的提问来源于stack exchange，提问作者PIXEL