我正在尝试用Java制作Pong游戏，但是从球拍上弹起球有一点问题。
我有两个拨片：左拨片1，右拨片2。
我的想法如下：ball_Y应该在桨的高度与ball_X的接触点之间应该是paddle width (PP1_width or PP2_width) +/- ball_radius
Paddle2正常运行，但球通过paddle1，我看不到我的错误。
这里是视频的样子；
这是桨弹跳的部分：
if(ball_Y > P1_Y && ball_Y < P1_Hit_Y){
if(ball_X < P1_Hit_X){
ball_Velocity_X *= -1;
ball_X = P1_Hit_X;
}
}
if (ball_Y > P2_Y && ball_Y < P2_Hit_Y){
if(ball_X > P2_Hit_X){
ball_Velocity_X *= -1;
ball_X = P2_Hit_X;
}
}
这是所有代码：
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import java.awt.event.*;
public class PongGame extends GameEngine{
public static void main(String args[]) {
// Warning - don't edit this function.
// Create a new game.
createGame(new PongGame());
}
int game_width, game_height;
double PP1_width, PP1_height, PP2_width, PP2_height;
double P1_X, P1_Y, P2_X, P2_Y;
double PP_Velocity;
boolean PP1_UP, PP1_DOWN, PP2_UP, PP2_DOWN;
double ball_X, ball_Y, ball_Radius, ball_Velocity_X, ball_Velocity_Y;
double P1_Hit_X, P1_Hit_Y, P2_Hit_X, P2_Hit_Y;
AudioClip wall_bounce;
//TODO: Create paddles and a ball
//Two paddles for two players: They will be controlled with W-S and UP-DOWN Keys
public void paddle1(){
drawSolidRectangle(P1_X, P1_Y, PP1_width, PP1_height);
}
public void paddle2(){
drawSolidRectangle(P2_X, P2_Y, PP2_width, PP2_height);
}
public void ball(){
drawSolidCircle(ball_X, ball_Y, ball_Radius);
}
//TODO: Update Paddles
//DONE: Sources from PhysicsDemo lecture
/**
* These methods allow us the update the window with each framerate so we will be able to move the
* paddles
*/
public void paddle1_update(double dt){
// Paddle 1 Up with W
if(PP1_UP == true){
P1_Y -= PP_Velocity * dt;
// Check paddle inside wall
if((P1_Y < 0) ) {
P1_Y = 0;
}
}
// Paddle 1 Down with S
if(PP1_DOWN == true){
P1_Y += PP_Velocity * dt;
// Check paddle inside wall
if(P1_Y > game_height-PP1_height){
P1_Y = game_height-PP1_height;
}
}
}
public void paddle2_update(double dt){
// Paddle 2 Up with Up Key
if(PP2_UP == true){
P2_Y -= PP_Velocity * dt;
// Check paddle inside wall
if((P2_Y < 0) ) {
P2_Y = 0;
}
}
// Paddle 2 Down with Down Key
if(PP2_DOWN == true){
P2_Y += PP_Velocity * dt;
// Check paddle inside wall
if(P2_Y > game_height-PP2_height){
P2_Y = game_height-PP2_height;
}
}
}
public void ball_update(double dt){
ball_X += ball_Velocity_X * dt;
ball_Y += ball_Velocity_Y * dt;
// Bouncing the ball from edge of the wals
if(ball_Y < ball_Radius) {
ball_Velocity_Y *= -1;
//Play wall bounce sound
playAudio(wall_bounce);
}else if (ball_Y > (game_height - ball_Radius)){
ball_Velocity_Y *= -1;
//Play wall bounce sound
playAudio(wall_bounce);
}
}
// Background
//TODO: Override init method in GameEngine
public void init(){
//Initialise Window size
game_width = 750;
game_height = 450;
//Position for Paddles
PP_Velocity = 250;
PP1_width = 10;
PP1_height = 100;
P1_X = 0;
P1_Y = 100;
PP2_width = 10;
PP2_height = 100;
P2_X = game_width - PP2_width;
P2_Y = 100;
//Initialise Keyboard variables
PP1_UP = false;
PP1_DOWN = false;
PP2_UP = false;
PP2_DOWN= false;
//Initialise Ball
ball_X = 250;
ball_Y = 250;
ball_Radius = 10;
ball_Velocity_X = 200;
ball_Velocity_Y = 200;
//Paddle ball bounce point
P1_Hit_X = PP1_width + ball_Radius;
P1_Hit_Y = P1_Y + PP1_height;
P2_Hit_X = P2_X - ball_Radius;
P2_Hit_Y = P2_Y + PP2_height;
/* NOTE: Sound Resources
* https://freesound.org/people/NoiseCollector/sounds/4391/
* https://freesound.org/people/NoiseCollector/sounds/4386/
*/
wall_bounce = loadAudio("Audio/wall_bounce.wav");
// paddle = loadAudio("Audio/paddle_bounce.wav");
//background = loadAudio("Audio/background.wav");
}
// Override abstract method update(double) in GameEngine
public void update(double dt){
paddle1_update(dt);
paddle2_update(dt);
ball_update(dt);
if(ball_Y > P1_Y && ball_Y < P1_Hit_Y){
if(ball_X < P1_Hit_X){
ball_Velocity_X *= -1;
ball_X = P1_Hit_X;
}
}
if (ball_Y > P2_Y && ball_Y < P2_Hit_Y){
if(ball_X > P2_Hit_X){
ball_Velocity_X *= -1;
ball_X = P2_Hit_X;
}
}
}
public void paintComponent() {
// Clear the background to black
setWindowSize(game_width, game_height);
changeBackgroundColor(black);
clearBackground(game_width, game_height);
changeColor(white);
drawLine(game_width/2, 0, game_width/2, game_height);
paddle1();
paddle2();
ball();
// Draw in black
changeColor(black);
}
//TODO: Key Listener for paddles ()
//DONE: KeyListener -> Space game example
// KeyPressed Event
public void keyPressed(KeyEvent event) {
// Left Arrow
if(event.getKeyCode() == KeyEvent.VK_W) {
PP1_UP = true;
}
// Right Arrow
if(event.getKeyCode() == KeyEvent.VK_S) {
PP1_DOWN = true;
}
// Space Button
if(event.getKeyCode() == KeyEvent.VK_UP) {
PP2_UP = true;
}
if(event.getKeyCode() == KeyEvent.VK_DOWN) {
PP2_DOWN = true;
}
}
// KeyReleased Event
public void keyReleased(KeyEvent event) {
// Left Arrow
if(event.getKeyCode() == KeyEvent.VK_W) {
PP1_UP = false;
}
// Right Arrow
if(event.getKeyCode() == KeyEvent.VK_S) {
PP1_DOWN = false;
}
// Space Button
if(event.getKeyCode() == KeyEvent.VK_UP) {
PP2_UP = false;
}
if(event.getKeyCode() == KeyEvent.VK_DOWN) {
PP2_DOWN = false;
}
}
}
答案 0 :(得分：1)
我认为您对此编码非常整齐，花了我一段时间才找出问题所在。但是，我认为这是由于未在桨更新方法中更新P1_Hit_Y和P2_Hit_Y引起的。所以：
if(PP1_UP == true){
P1_Y -= PP_Velocity * dt;
P1_Hit_Y -= PP_Velocity *dt;
// Check paddle inside wall
if((P1_Y < 0) ) {
P1_Y = 0;
P1_Hit_Y = 0;
}
}
// Paddle 1 Down with S
if(PP1_DOWN == true){
P1_Y += PP_Velocity * dt;
P1_Hit_Y += PP_Velocity *dt;
// Check paddle inside wall
if(P1_Y > game_height-PP1_height){
P1_Y = game_height-PP1_height;
P1_Hit_Y = game_height;
}
}
与paddle2相同。
希望这会有所帮助！