LibGDX设置加速错误

Question

我正在学习LibGDX进行游戏开发，我的游戏在Box2D上运行的很好，但只剩下一件事，为我的敌人设置加速度，当我尝试这样做时（我添加了float timer = 0;值，在我的EnemyUserData类创建一个渲染方法和下面的代码添加到它

@Override 
    public void render(float delta, float speed) { 
     timer += Gdx.graphics.getDeltaTime(); //returns time between two frames 
     if (timer > 10) { //after 10 seconds 
      linearVelocity = linearVelocity * 1.1F; 
      timer = 0; //reset timer 
     } 
    } 
} 

但该计划开始与错误，如抱怨：

Error:(20, 25) Gradle: error: incompatible types: float cannot be converted to Vector2Error:(33, 4) Gradle: error: method does not override or implement a method from a supertypeError:(37, 44) Gradle: error: bad operand types for binary operator '*' 
first type: Vector2 
second type: float 

EnemyUserData类的情况下，你需要更多的信息：

package com.avoidcrashjump.box2d; 

import com.avoidcrashjump.Constants; 
import com.avoidcrashjump.enums.UserDataType; 
import com.badlogic.gdx.Gdx; 
import com.badlogic.gdx.graphics.GL20; 
import com.badlogic.gdx.math.Vector2; 

/** 
* Created by Felipe on 3/1/2016. 
*/ 
public class EnemyUserData extends UserData { 

    float timer = 0; 
    float speed = 200f; 
    private Vector2 linearVelocity; 

    public EnemyUserData(float width, float height) { 
     super(width, height); 
     userDataType = UserDataType.ENEMY; 
     linearVelocity = speed; 

    } 

    public void setLinearVelocity(Vector2 linearVelocity) { 
     this.linearVelocity = linearVelocity; 
    } 

    public Vector2 getLinearVelocity() { 
     return linearVelocity; 
    } 


    @Override 
    public void render(float delta, float speed) { 
     timer += Gdx.graphics.getDeltaTime(); //returns time between two frames 
     if (timer > 10) { //after 10 seconds 
      linearVelocity = linearVelocity * 1.1F; 
      timer = 0; //reset timer 
     } 
    } 
} 

请问有人请向我解释我做错了什么？我尝试从Vector2更改为浮动，并没有工作。对于EnemyUserData类新的代码如下：

package com.avoidcrashjump.box2d; 

import com.avoidcrashjump.Constants; 
import com.avoidcrashjump.enums.UserDataType; 
import com.badlogic.gdx.Gdx; 
import com.badlogic.gdx.graphics.GL20; 
import com.badlogic.gdx.math.Vector2; 

/** 
* Created by Felipe on 3/1/2016. 
*/ 
public class EnemyUserData extends UserData { 

    float timer = 0; 
    float speed = 200f; 
    private Vector2 linearVelocity; 

    public EnemyUserData(float width, float height) { 
     super(width, height); 
     userDataType = UserDataType.ENEMY; 
     linearVelocity = speed; 

    } 

    public void setLinearVelocity(Vector2 linearVelocity) { 
     this.linearVelocity = linearVelocity; 
    } 

    public Vector2 getLinearVelocity() { 
     return linearVelocity; 
    } 


    @Override 
    public void render(float delta, float speed) { 
     timer += Gdx.graphics.getDeltaTime(); //returns time between two frames 
     if (timer > 10) { //after 10 seconds 
      linearVelocity = linearVelocity * 1.1F; 
      timer = 0; //reset timer 
     } 
    } 
} 

这是我必须做我的比赛只是时间问题。

Answer 1

基本物理学：速度是一个向量，你有单独的速度，每个轴（X，Y，Z ...），所以你不能只是不能火腿拳头速度成一个简单的标量值。

看来LibGDX的载体不会覆盖*运营商，所以你必须调整像这样的载体：

linearVelocity.scl(1.1);