我正在用Java制作乒乓球类游戏,我试图使球从墙壁上弹起,但是只要球撞到球,它只会停下来,不会从墙壁上反射出来,我似乎无法找出原因。
处理球运动的球类
public class Ball {
private double x;
private double y;
private double time;
private double xreflection=1.0;
private double yreflection=1.0;
private BallTrajectory traj=new BallTrajectory(20, 20);
public Ball(double x, double y) {
this.x=x;
this.y=y;
}
public void tick() {
time+=1.0/60.0;
if(x==0)
xreflection=1.0;
else if(x==Game.Width-15)
xreflection=-1.0;
if(y==0)
yreflection=1.0;
else if(y==Game.Height-15)
yreflection=-1.0;
x+=traj.xvel()*xreflection;
y-=traj.yvel(time)*yreflection;
}
public void render(Graphics g) {
g.setColor(Color.pink);
g.fillOval((int)x, (int)y, 15,15);
}
}
此类处理球以弹丸形式运动时的轨迹
public class BallTrajectory {
private double initvel;
private double theta;
public BallTrajectory(double initvel, double theta) {
this.initvel=initvel;
this.theta=theta;
}
public double xvel() {
double xvelo=initvel*Math.cos(Math.toRadians(theta));
return xvelo;
}
public double yvel(double time) {
double yvelo=initvel*Math.sin(Math.toRadians(theta))-(9.8*time);
return yvelo;
}
public double xpos(double time) {
double xpos=initvel*Math.cos(Math.toRadians(theta))*time;
return xpos;
}
public double ypos(double time) {
double ypos=initvel*Math.sin(Math.toRadians(theta))*time-.5*9.8*Math.pow(time, 2);
return ypos;
}
答案 0 :(得分:2)
如果不进行大量测试,我建议x
不可能完全等于Game.Width
或0
。相反,您应该测试该值是否在“范围内”,例如...
public void tick() {
time += 1.0 / 60.0;
if (x <= 0) {
xreflection = 1.0;
} else if (x >= Game.Width - 15) {
xreflection = -1.0;
}
if (y <= 0) {
yreflection = 1.0;
} else if (y >= Game.Height - 15) {
yreflection = -1.0;
}
x += traj.xvel() * xreflection;
y -= traj.yvel(time) * yreflection;
}
您还应该开始花时间学习如何调试代码,这是您需要做的很多事情,从检查桌面逻辑到使用打印语句和调试器