【Unity3D】实现横版2D游戏角色二段跳、蹬墙跳、扶墙下滑

一、二段跳、蹬墙跳

二、扶墙下滑

一、二段跳、蹬墙跳

GitHub - prime31/CharacterController2D

下载工程后直接打开demo场景：DemoScene（Unity 2019.4.0f1项目环境）

Player物体上的CharacterController2D，Mask添加Wall层（自定义墙体层）

将场景里其中一个障碍物设置为Wall层 Wall标签并拉伸为墙体高度

Player物体上的Demo Scene脚本控制玩家移动二段跳蹬墙跳

蹬墙跳要调整好Jump On Wall H Force 横向力和 Jump On Wall V Force 纵向力数值才能表现正常，其中 V Force 是在 1的基础上的增量值，这里的力并非物理力实际是速度增量倍率。

跳跃对Y轴速度影响是用公式：根号2gh
代码则是：Mathf.Sqrt(2f * jumpHeight * -gravity)，加速度是重力反方向，跳跃高度固定，则计算出了速度增量，之后用它乘以（1+V Force）得出的一个对Y轴速度影响的增量。

上例子中速度增量根号2gh是8.48，因此每次蹬墙跳Y速度增量是8.48*1.335=11.32
代码默认有重力对Y轴速度影响：_velocity.y += gravity * Time.deltaTime; 即每秒Y轴速度会减去重力加速度（墙上为-24，地面为-25）若帧数是30，则每帧会减少0.8。具体可以将_velocity参数公开查看变化，实际蹬墙跳会离开墙体，重力加速度为-25，可自行调整这些参数来达到理想效果

修改部分代码：

    private float rawGravity;private int jumpLevel;//跳跃阶段 1段跳 2段跳private int dir; //朝向 -1左 1右public LayerMask jumpOnWallMask = 0;//墙体Layer层遮罩private bool isHoldWall; //是否在墙上public float jumpOnWallHForce = 1; //墙上跳跃横向力度public float jumpOnWallVForce = 2; //墙上跳跃纵向力度public float gravityOnWall = -24f;void Awake(){//... ...rawGravity = gravity;}void Update(){if (_controller.isGrounded){gravity = rawGravity;_velocity.y = 0;jumpLevel = 0;}//朝着dir方向发射长度为(碰撞体宽度+自身皮肤厚度)的射线RaycastHit2D hit = Physics2D.Linecast(playerBottomTrans.position, playerBottomTrans.position + new Vector3(dir * (Mathf.Abs(transform.localScale.x) * _controller.boxCollider.size.x / 2f + _controller.skinWidth), 0, 0), jumpOnWallMask);if (hit && hit.collider.tag == "Wall"){isHoldWall = true;gravity = gravityOnWall; //可调整由rawGravity随着时间降低到gravityOnWall}else{isHoldWall = false;gravity = rawGravity;}if ( Input.GetKey( KeyCode.RightArrow ) ){//... ...dir = 1;}else if( Input.GetKey( KeyCode.LeftArrow ) ){//... ...dir = -1;}else { //... ...}//原点击UpArrow代码删除，改为如下//点击向上if (Input.GetKeyDown(KeyCode.UpArrow)){//未在墙上if (!isHoldWall){//在地面起跳 （1级跳）if (_controller.isGrounded){jumpLevel = 1;_velocity.y = Mathf.Sqrt(2f * jumpHeight * -gravity);_animator.Play(Animator.StringToHash("Jump"));}else{//1级跳途中，再次起跳（2级跳）if(jumpLevel == 1){jumpLevel = 2;_velocity.y = Mathf.Sqrt(2f * jumpHeight * -gravity);_animator.Play("Jump");}}}else{//墙上可连续起跳，若想限制只能2段跳，则要类似上面代码写法//在墙上_velocity.x += -dir * jumpOnWallHForce;//仅在墙上会受到重力因此想再次起跳上升 必须比重力还要大的力 1+jumpOnWallForce//若在墙体上且在地面上，则不要加这个jumpOnWallVForce力，否则贴墙就起跳会让你飞起来！_velocity.y += Mathf.Sqrt(2f * jumpHeight * -gravity) * (1 + (_controller.isGrounded ? 0 : jumpOnWallVForce));_animator.Play("Jump");}}}

完整代码：

using UnityEngine;
using System.Collections;
using Prime31;public class DemoScene : MonoBehaviour
{// movement configprivate float rawGravity;public float gravity = -25f;public float runSpeed = 8f;public float groundDamping = 20f; // how fast do we change direction? higher means fasterpublic float inAirDamping = 5f;public float jumpHeight = 3f;[HideInInspector]private float normalizedHorizontalSpeed = 0;private CharacterController2D _controller;private Animator _animator;private RaycastHit2D _lastControllerColliderHit;private Vector3 _velocity;private int jumpLevel;//跳跃阶段 1段跳 2段跳private int dir; //朝向 -1左 1右public LayerMask jumpOnWallMask = 0;//墙体Layer层遮罩private bool isHoldWall; //是否在墙上public float jumpOnWallHForce = 1; //墙上跳跃横向力度public float jumpOnWallVForce = 2; //墙上跳跃纵向力度public float gravityOnWall = -24f;void Awake(){_animator = GetComponent<Animator>();_controller = GetComponent<CharacterController2D>();// listen to some events for illustration purposes_controller.onControllerCollidedEvent += onControllerCollider;_controller.onTriggerEnterEvent += onTriggerEnterEvent;_controller.onTriggerExitEvent += onTriggerExitEvent;rawGravity = gravity;}#region Event Listenersvoid onControllerCollider( RaycastHit2D hit ){// bail out on plain old ground hits cause they arent very interestingif( hit.normal.y == 1f )return;// logs any collider hits if uncommented. it gets noisy so it is commented out for the demo//Debug.Log( "flags: " + _controller.collisionState + ", hit.normal: " + hit.normal );}void onTriggerEnterEvent( Collider2D col ){Debug.Log( "onTriggerEnterEvent: " + col.gameObject.name );}void onTriggerExitEvent( Collider2D col ){Debug.Log( "onTriggerExitEvent: " + col.gameObject.name );}#endregion// the Update loop contains a very simple example of moving the character around and controlling the animationvoid Update(){if (_controller.isGrounded){gravity = rawGravity;_velocity.y = 0;jumpLevel = 0;}//朝着dir方向发射长度为(碰撞体一半宽度+自身皮肤厚度)的射线RaycastHit2D hit = Physics2D.Linecast(playerBottomTrans.position, playerBottomTrans.position + new Vector3(dir * (Mathf.Abs(transform.localScale.x) * _controller.boxCollider.size.x / 2f + _controller.skinWidth), 0, 0), jumpOnWallMask);if (hit && hit.collider.tag == "Wall"){isHoldWall = true;gravity = gravityOnWall; //可调整由rawGravity随着时间降低到gravityOnWall}else{isHoldWall = false;gravity = rawGravity;}if ( Input.GetKey( KeyCode.RightArrow ) ){normalizedHorizontalSpeed = 1;dir = 1;if( transform.localScale.x < 0f )transform.localScale = new Vector3( -transform.localScale.x, transform.localScale.y, transform.localScale.z );if( _controller.isGrounded )_animator.Play( Animator.StringToHash( "Run" ) );}else if( Input.GetKey( KeyCode.LeftArrow ) ){normalizedHorizontalSpeed = -1;dir = -1;if( transform.localScale.x > 0f )transform.localScale = new Vector3( -transform.localScale.x, transform.localScale.y, transform.localScale.z );if( _controller.isGrounded )_animator.Play( Animator.StringToHash( "Run" ) );}else{normalizedHorizontalSpeed = 0;if( _controller.isGrounded )_animator.Play( Animator.StringToHash( "Idle" ) );}//点击向上if (Input.GetKeyDown(KeyCode.UpArrow)){//未在墙上if (!isHoldWall){//在地面起跳 （1级跳）if (_controller.isGrounded){jumpLevel = 1;_velocity.y = Mathf.Sqrt(2f * jumpHeight * -gravity);_animator.Play(Animator.StringToHash("Jump"));}else{//1级跳途中，再次起跳（2级跳）if(jumpLevel == 1){jumpLevel = 2;_velocity.y = Mathf.Sqrt(2f * jumpHeight * -gravity);_animator.Play("Jump");}}}else{//墙上可连续起跳，若想限制只能2段跳，则要类似上面代码写法//在墙上_velocity.x += -dir * jumpOnWallHForce;//仅在墙上会受到重力因此想再次起跳上升 必须比重力还要大的力 1+jumpOnWallForce//若在墙体上且在地面上，则不要加这个jumpOnWallVForce力，否则贴墙就起跳会让你飞起来！_velocity.y += Mathf.Sqrt(2f * jumpHeight * -gravity) * (1 + (_controller.isGrounded ? 0 : jumpOnWallVForce));_animator.Play("Jump");}}// apply horizontal speed smoothing it. dont really do this with Lerp. Use SmoothDamp or something that provides more controlvar smoothedMovementFactor = _controller.isGrounded ? groundDamping : inAirDamping; // how fast do we change direction?_velocity.x = Mathf.Lerp( _velocity.x, normalizedHorizontalSpeed * runSpeed, Time.deltaTime * smoothedMovementFactor );// apply gravity before moving_velocity.y += gravity * Time.deltaTime;//在地面上，按住下键不松开会蓄力将起跳速度*3倍// if holding down bump up our movement amount and turn off one way platform detection for a frame.// this lets us jump down through one way platformsif( _controller.isGrounded && Input.GetKey( KeyCode.DownArrow ) ){_velocity.y *= 3f;_controller.ignoreOneWayPlatformsThisFrame = true;}_controller.move( _velocity * Time.deltaTime );// grab our current _velocity to use as a base for all calculations_velocity = _controller.velocity;}}

蹬墙跳问题：

因此你要将重力、X Force 、Y Force、JumpHeight都要调整好才能呈现出正常的蹬墙跳，目前来看仅靠简单调整Y Force是不行的，要么力度太大要么力度太小。

二、扶墙下滑

Asset Store使用免费资源：Hero Knight - Pixel Art

		if(!_controller.isGrounded){if (isHoldWall){//必须是坠落时 if (_velocity.y < 0){//人物顶点发起射线检测到墙体 才算是完整在墙体上 播放扶墙动画RaycastHit2D hit2 = Physics2D.Linecast(playerTopTrans.position, playerTopTrans.position +new Vector3(dir * (Mathf.Abs(transform.localScale.x) * _controller.boxCollider.size.x / 2f + _controller.skinWidth), 0, 0), jumpOnWallMask);if (hit2 && hit2.collider.tag == "Wall"){_animator.Play(Animator.StringToHash("WallSlide"));}}}else{//避免影响1级跳（离地后）以及2级跳时立即切到Fall动画,代码里没有主动将jumpLevel在1级跳或2级跳结束后将jumpLevel改为0的操作，仅在蹬墙跳重置为0if (jumpLevel != 2 && jumpLevel != 1){_animator.Play(Animator.StringToHash("Fall"));}}}

蹬墙跳时进行重置jumpLevel为0状态

Animator如上所示，Roll和Jump是无条件直接结束时回到Fall，仅适用于本案例不会在平地滚动。

可做辅助射线查看是否正常射线检测到墙体

//朝着dir方向发射长度为(碰撞体宽度+自身皮肤厚度)的射线
Debug.DrawRay(playerTopTrans.position, new Vector3(dir * (Mathf.Abs(transform.localScale.x) * _controller.boxCollider.size.x / 2 + _controller.skinWidth), 0, 0), Color.red);
Debug.DrawRay(playerBottomTrans.position, new Vector3(dir * (Mathf.Abs(transform.localScale.x) *_controller.boxCollider.size.x / 2 + _controller.skinWidth), 0, 0), Color.red);