1
這是正確的網站來問這個問題，因爲我現在已被兩次提到另一個網站。物理彈跳球
我試圖用真實的物理學來創建彈跳球。此刻，當球撞到對方時，他們會以同樣的方向反彈回來，現在，我已經在網上搜索瞭如何做到這一點，但我只能找到如何檢測碰撞的事情，而不是什麼之後去做。我對物理學瞭解不多，在我能夠做到這一點之前，我應該先學習他們的主題？這是一幅我想象的球如何在現實生活中反彈的圖像。這是如何工作的？
how I think it should work http://thewombatguru.nl/Bouncing.png
另外，我要在我的代碼不好的做法？ （也許，但我學到了很多東西，我喜歡它）
這是我當前的代碼：
Asteroids.java
package Asteroids;
import javax.swing.*;
public class Asteroids {
public static void createAndShowGui() {
GamePanel gamePanel = new GamePanel();
JFrame frame = new JFrame("Asteroids");
frame.getContentPane().add(gamePanel);
frame.pack();
frame.setVisible(true);
frame.setResizable(false);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setLocation(2000, 50);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
GamePanel.java
package Asteroids;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
public class GamePanel extends JPanel implements ActionListener {
private final int WIDTH = 1000;
private final int HEIGHT = 1000;
Timer animationTimer;
ArrayList<Rock> rocks;
public GamePanel() {
Dimension preferredDimension = new Dimension(WIDTH, HEIGHT);
setPreferredSize(preferredDimension);
animationTimer = new Timer(10, this);
setUp();
}
public void setUp() {
rocks = new ArrayList<>();
rocks.add(new Rock(475, 1000, 0, -1));
rocks.add(new Rock(0, 500, 1, 0));
//rocks.add(new Rock(300, 270, -2, 2));
//rocks.add(new Rock(400, 315, -5, -1));
animationTimer.start();
}
@Override
public void actionPerformed(ActionEvent e) {
repaint();
for (Rock rock : rocks) {
for (Rock rockToCheck : rocks) {
if (!rock.equals(rockToCheck)) {
rock.checkForCollisionWithRocks(rockToCheck);
}
}
rock.checkForCollisionWithFrame(WIDTH, HEIGHT);
rock.setxPos(rock.getxPos() + rock.getxVelocity());
rock.setyPos(rock.getyPos() + rock.getyVelocity());
}
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
RenderingHints mainRenderingHints = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHints(mainRenderingHints);
for (Rock rock : rocks) {
rock.display(g2d);
}
g2d.dispose();
}
}
Rock.java
package Asteroids;
import java.awt.*;
public class Rock {
private int xPos;
private int yPos;
private int rockWidth;
private int rockHeight;
private int xVelocity;
private int yVelocity;
private int rockRadius;
private Color rockColor;
public Rock(int xPos, int yPos, int xVelocity, int yVelocity) {
this.xPos = xPos;
this.yPos = yPos;
this.xVelocity = xVelocity;
this.yVelocity = yVelocity;
rockWidth = 50;
rockHeight = rockWidth;
rockRadius = rockWidth/2;
rockColor = new Color((int) (Math.random() * 255),(int) (Math.random() * 255),(int) (Math.random() * 255));
}
public void setxPos(int xPos) {
this.xPos = xPos;
}
public int getxPos() {
return xPos;
}
public int getRockWidth() {
return rockWidth;
}
public void setRockWidth(int rockWidth) {
this.rockWidth = rockWidth;
}
public int getRockHeight() {
return rockHeight;
}
public void setRockHeight(int rockHeight) {
this.rockHeight = rockHeight;
}
public int getyPos() {
return yPos;
}
public void setyPos(int yPos) {
this.yPos = yPos;
}
public int getxVelocity() {
return xVelocity;
}
public void setxVelocity(int xVelocity) {
this.xVelocity = xVelocity;
}
public int getyVelocity() {
return yVelocity;
}
public void setyVelocity(int yVelocity) {
this.yVelocity = yVelocity;
}
public int getRockRadius() {
return rockRadius;
}
public void setRockRadius(int rockRadius) {
this.rockRadius = rockRadius;
}
public void checkForCollisionWithRocks(Rock rock) {
int radiusOfBoth = rock.getRockRadius() + rockRadius;
int horDistance = Math.abs((rock.getxPos() + rock.getRockRadius()) - (xPos + rockRadius));
int verDistance = Math.abs((rock.getyPos() + rock.getRockRadius()) - (yPos + rockRadius));
int diagDistance = (int) Math.sqrt(Math.pow(horDistance, 2) + Math.pow(verDistance, 2));
if (diagDistance <= radiusOfBoth) {
xVelocity = -xVelocity;
yVelocity = -yVelocity;
rock.setxVelocity(-rock.getxVelocity());
rock.setyVelocity(-rock.getyVelocity());
rock.setxPos(rock.getxPos() + rock.getxVelocity());
rock.setyPos(rock.getyPos() + rock.getyVelocity());
}
}
public void checkForCollisionWithFrame(final int WIDTH, final int HEIGHT) {
if (xPos < 0) {
xVelocity *= -1;
xPos = 0;
} else if (xPos + rockWidth > WIDTH) {
xVelocity *= -1;
xPos = WIDTH - rockWidth;
}
if (yPos < 0) {
yVelocity *= -1;
yPos = 0;
} else if (yPos + rockHeight > HEIGHT) {
yVelocity *= -1;
yPos = HEIGHT - rockHeight;
}
}
public void display(Graphics2D g2d) {
g2d.setColor(rockColor);
g2d.fillOval(xPos, yPos, rockWidth, rockHeight);
}
}
任何人都可以幫忙嗎？
如果通過*之後會發生什麼，你的意思是每個組件的速度（速度+方向），我認爲你應該讀一些關於彈性碰撞的內容。你可以問[physics.stackexchange.com]（http://physics.stackexchange.com/）一些數學模型，我認爲值得一提的是一些背景知識，因爲它可以非常快速地變得非常複雜。最後，對於代碼評論，請轉到[codereview.stackexchange.com]（http://codereview.stackexchange.com/）。 – npinti
@npinti是的，我的意思是速度和方向，但我只想從方向開始，因爲我所有的球都以相同的速度移動，而且我不希望它們在碰到某物時「失去能量」。我會做一些關於彈性碰撞的閱讀。 codereview在這裏寄給我 –
我認爲這將是一個很好的閱讀，除非你已經消化它：http://en.wikipedia.org/wiki/Elastic_collision#Two-Dimensional_Collision_With_Two_Moving_Objects – laune