无法实施 object 向鼠标 JAVA 的旋转
Failed to implement object rotation towards mouse JAVA
正如标题所说，就是做不到。尝试了很久，还是失败了。 （我是 java 的新手）
我的图像或 fillRect 旋转了一点，但没有按应有的方式旋转
整个代码 +imgs
*MAIN game class*
package game.main;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
public class game extends Canvas implements Runnable{
private static final long serialVersionUID = -392333887196083915L;
public static final int WIDTH = 640, HEIGHT = WIDTH / 12 * 9;
private Thread thread;
private boolean running = false;
private Handler handler;
public game(){
handler = new Handler();
new window(WIDTH, HEIGHT,"Game",this);
handler.addObject(new Player(WIDTH/2-32, HEIGHT/2-32, ID.Player, handler));
}
public synchronized void start(){
thread = new Thread(this);
thread.start();
running = true;
}
public synchronized void stop(){
try{
thread.join();
running = false;
}catch(Exception e){
e.printStackTrace();
}
}
// ↓ game loop for update
public void run(){
this.requestFocus();
long lastTime = System.nanoTime();
double amountOfTicks = 60.0;
double ns = 1000000000 / amountOfTicks;
double delta = 0;
long timer = System.currentTimeMillis();
int frames = 0;
while(running){
long now = System.nanoTime();
delta += (now - lastTime) / ns;
lastTime = now;
while(delta >= 1){
tick();
delta--;
}
if(running)
render();
frames++;
if(System.currentTimeMillis() - timer > 1000){
timer += 1000;
System.out.print("FPS:" + frames);
frames = 0;
}
}
stop();
}
private void tick(){
handler.tick();
}
private void render(){
BufferStrategy bs = this.getBufferStrategy();
if(bs == null){
this.createBufferStrategy(3);
return;
}
Graphics g = bs.getDrawGraphics();
g.setColor(Color.black);
g.fillRect(0, 0, WIDTH, HEIGHT);
handler.render(g);
g.dispose();
bs.show();
}
public static void main(String args[]) {
new game();
}
}
<br>
package game.main;
import java.awt.Graphics;
public abstract class GameObject {
protected float x, y;
protected ID id;
protected float velX, velY;
public GameObject(float x, float y, ID id){
this.x = x;
this.y = y;
this.id = id;
}
public abstract void tick();
public abstract void render(Graphics g);
public void setX(int x){
this.x = x;
}
public void setY(int y){
this.y = y;
}
public float getX(){
return x;
}
public float getY(){
return y;
}
public void setId(ID id){
this.id = id;
}
public ID getId(){
return id;
}
public void setVelX(int velX){
this.velX = velX;
}
public void setVelY(int velY){
this.velY = velY;
}
public float getVelX(){
return velX;
}
public float getVelY(){
return velY;
}
}
*GameObject class*
package game.main;
import java.awt.Graphics;
public abstract class GameObject {
protected float x, y;
protected ID id;
protected float velX, velY;
public GameObject(float x, float y, ID id){
this.x = x;
this.y = y;
this.id = id;
}
public abstract void tick();
public abstract void render(Graphics g);
public void setX(int x){
this.x = x;
}
public void setY(int y){
this.y = y;
}
public float getX(){
return x;
}
public float getY(){
return y;
}
public void setId(ID id){
this.id = id;
}
public ID getId(){
return id;
}
public void setVelX(int velX){
this.velX = velX;
}
public void setVelY(int velY){
this.velY = velY;
}
public float getVelX(){
return velX;
}
public float getVelY(){
return velY;
}
}
*Handler class*
package game.main;
import java.awt.Graphics;
import java.util.LinkedList;
// render all objects
public class Handler {
LinkedList<GameObject> object = new LinkedList<GameObject>();
public void tick(){
for(int i = 0; i < object.size(); i++){
GameObject tempObject = object.get(i);
tempObject.tick();
}
}
public void render(Graphics g){
for(int i = 0; i <object.size();i++){
GameObject tempObject = object.get(i);
tempObject.render(g);
}
}// handling adding objects
public void addObject(GameObject object){
this.object.add(object);
}
}
*window class*
package game.main;
import java.awt.Canvas;
import java.awt.Dimension;
import javax.swing.JFrame;
public class window extends Canvas{
private static final long serialVersionUID = 3010486623466540351L;
public window(int width, int height, String title, game game){
JFrame frame = new JFrame(title);
frame.setPreferredSize(new Dimension(width, height));
frame.setMaximumSize(new Dimension(width, height));
frame.setMinimumSize(new Dimension(width, height));
// X button
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// ¤ button maximize
frame.setResizable(false);
// window appear in middle of screen instead of top left corner
frame.setLocationRelativeTo(null);
// add game to window
frame.add(game);
frame.setVisible(true);
game.start();
}
}
* ID class*
package game.main;
public enum ID {
Player();
}
仅向此添加代码 class
*Player class*
package game.main;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.MouseInfo;
import java.awt.Point;
import java.awt.PointerInfo;
public class Player extends GameObject{
Handler handler;
public Player(int x, int y, ID id, Handler handler) {
super(x, y, id);
this.handler = handler;
}
public void tick() {
}
public void render(Graphics g) {
///////////ADDED//////////////////
PointerInfo a = MouseInfo.getPointerInfo();
Point b = a.getLocation();
int mouseX = (int) b.getX();
int mouseY = (int) b.getY();
int centerX = game.WIDTH / 2;
int centerY = game.HEIGHT / 2;
double angle = Math.atan2(centerY - mouseY, centerX - mouseX) - Math.PI / 2;
((Graphics2D)g).rotate(angle, centerX, centerY);
//////////////////////////////
g.setColor(Color.white);
g.fillRect((int)x, (int)y, 32, 32);
}
}
它现在是如何工作的以及我想要它的方式。白色 - 原创/绿色 - 我想要这样
Example 1
Example 2
我查看了这个来源：
Get mouse possition (Whosebug)
Java 2d rotation in direction mouse point (Whosebug)
Rotating an object to point towards the mouse
问题是 MouseInfo.getPointerInfo().getLocation(); returns 绝对鼠标位置。您需要相对于您的游戏的鼠标位置 canvas。你可以修改你的gameclass中的render方法如下：
Point mouseLocation = MouseInfo.getPointerInfo().getLocation();
SwingUtilities.convertPointFromScreen(mouseLocation, this);
handler.render(g, mouseLocation);
这需要您相应地修改渲染方法的方法签名。这只是将游戏 canvas 中的 mouseLocation 传递给玩家渲染方法的一种方法。
在播放器的渲染方法中使用 mouseLocation 而不是 MouseInfo.getPointerInfo().getLocation();。
为了将玩家置于 canvas 的中心并使他围绕他的中心旋转，您还需要进行一些更改：
- 您应该设置游戏大小 canvas 而不是 window(
JFrame)。为此，请在游戏 canvas 上调用 setPreferredSize(new Dimension(width, height)); 并在 frame.setVisible(true) 之前调用 frame.pack()。这将确保您的游戏 canvas 具有 WIDTH 和 HEIGHT. 指定的大小
- 您可以将两个字段
refx 和 refy 添加到您的 GameObject class 来描述您的 GameObject 的参考点（例如它的中心） .然后，您可以通过调用 new Player(WIDTH/2-16, HEIGHT/2-16, 16, 16, ID.Player, handler) 来构造一个新的 Player，玩家的初始位置位于 (WIDTH/2-16, HEIGHT/2-16) 及其参考点是 (16,16) - 当玩家由 32x32 矩形表示时玩家的中心。
- 在 Player 的渲染方法中，用
int centerX = Math.round(x + refx); int centerY = Math.round(y + refy); 初始化你想要旋转的中心，其中 (x,y) 是你想要旋转的对象的位置和 (refx, refy) 你想要的点相对于对象的位置旋转（例如 x = WIDTH/2-16，y = HEIGTH/2-16，refx = 16，refy = 16）。
正如标题所说，就是做不到。尝试了很久，还是失败了。 （我是 java 的新手）
我的图像或 fillRect 旋转了一点，但没有按应有的方式旋转
整个代码 +imgs
*MAIN game class*
package game.main;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
public class game extends Canvas implements Runnable{
private static final long serialVersionUID = -392333887196083915L;
public static final int WIDTH = 640, HEIGHT = WIDTH / 12 * 9;
private Thread thread;
private boolean running = false;
private Handler handler;
public game(){
handler = new Handler();
new window(WIDTH, HEIGHT,"Game",this);
handler.addObject(new Player(WIDTH/2-32, HEIGHT/2-32, ID.Player, handler));
}
public synchronized void start(){
thread = new Thread(this);
thread.start();
running = true;
}
public synchronized void stop(){
try{
thread.join();
running = false;
}catch(Exception e){
e.printStackTrace();
}
}
// ↓ game loop for update
public void run(){
this.requestFocus();
long lastTime = System.nanoTime();
double amountOfTicks = 60.0;
double ns = 1000000000 / amountOfTicks;
double delta = 0;
long timer = System.currentTimeMillis();
int frames = 0;
while(running){
long now = System.nanoTime();
delta += (now - lastTime) / ns;
lastTime = now;
while(delta >= 1){
tick();
delta--;
}
if(running)
render();
frames++;
if(System.currentTimeMillis() - timer > 1000){
timer += 1000;
System.out.print("FPS:" + frames);
frames = 0;
}
}
stop();
}
private void tick(){
handler.tick();
}
private void render(){
BufferStrategy bs = this.getBufferStrategy();
if(bs == null){
this.createBufferStrategy(3);
return;
}
Graphics g = bs.getDrawGraphics();
g.setColor(Color.black);
g.fillRect(0, 0, WIDTH, HEIGHT);
handler.render(g);
g.dispose();
bs.show();
}
public static void main(String args[]) {
new game();
}
}
<br>
package game.main;
import java.awt.Graphics;
public abstract class GameObject {
protected float x, y;
protected ID id;
protected float velX, velY;
public GameObject(float x, float y, ID id){
this.x = x;
this.y = y;
this.id = id;
}
public abstract void tick();
public abstract void render(Graphics g);
public void setX(int x){
this.x = x;
}
public void setY(int y){
this.y = y;
}
public float getX(){
return x;
}
public float getY(){
return y;
}
public void setId(ID id){
this.id = id;
}
public ID getId(){
return id;
}
public void setVelX(int velX){
this.velX = velX;
}
public void setVelY(int velY){
this.velY = velY;
}
public float getVelX(){
return velX;
}
public float getVelY(){
return velY;
}
}
*GameObject class*
package game.main;
import java.awt.Graphics;
public abstract class GameObject {
protected float x, y;
protected ID id;
protected float velX, velY;
public GameObject(float x, float y, ID id){
this.x = x;
this.y = y;
this.id = id;
}
public abstract void tick();
public abstract void render(Graphics g);
public void setX(int x){
this.x = x;
}
public void setY(int y){
this.y = y;
}
public float getX(){
return x;
}
public float getY(){
return y;
}
public void setId(ID id){
this.id = id;
}
public ID getId(){
return id;
}
public void setVelX(int velX){
this.velX = velX;
}
public void setVelY(int velY){
this.velY = velY;
}
public float getVelX(){
return velX;
}
public float getVelY(){
return velY;
}
}
*Handler class*
package game.main;
import java.awt.Graphics;
import java.util.LinkedList;
// render all objects
public class Handler {
LinkedList<GameObject> object = new LinkedList<GameObject>();
public void tick(){
for(int i = 0; i < object.size(); i++){
GameObject tempObject = object.get(i);
tempObject.tick();
}
}
public void render(Graphics g){
for(int i = 0; i <object.size();i++){
GameObject tempObject = object.get(i);
tempObject.render(g);
}
}// handling adding objects
public void addObject(GameObject object){
this.object.add(object);
}
}
*window class*
package game.main;
import java.awt.Canvas;
import java.awt.Dimension;
import javax.swing.JFrame;
public class window extends Canvas{
private static final long serialVersionUID = 3010486623466540351L;
public window(int width, int height, String title, game game){
JFrame frame = new JFrame(title);
frame.setPreferredSize(new Dimension(width, height));
frame.setMaximumSize(new Dimension(width, height));
frame.setMinimumSize(new Dimension(width, height));
// X button
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// ¤ button maximize
frame.setResizable(false);
// window appear in middle of screen instead of top left corner
frame.setLocationRelativeTo(null);
// add game to window
frame.add(game);
frame.setVisible(true);
game.start();
}
}
* ID class*
package game.main;
public enum ID {
Player();
}
仅向此添加代码 class
*Player class*
package game.main;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.MouseInfo;
import java.awt.Point;
import java.awt.PointerInfo;
public class Player extends GameObject{
Handler handler;
public Player(int x, int y, ID id, Handler handler) {
super(x, y, id);
this.handler = handler;
}
public void tick() {
}
public void render(Graphics g) {
///////////ADDED//////////////////
PointerInfo a = MouseInfo.getPointerInfo();
Point b = a.getLocation();
int mouseX = (int) b.getX();
int mouseY = (int) b.getY();
int centerX = game.WIDTH / 2;
int centerY = game.HEIGHT / 2;
double angle = Math.atan2(centerY - mouseY, centerX - mouseX) - Math.PI / 2;
((Graphics2D)g).rotate(angle, centerX, centerY);
//////////////////////////////
g.setColor(Color.white);
g.fillRect((int)x, (int)y, 32, 32);
}
}
它现在是如何工作的以及我想要它的方式。白色 - 原创/绿色 - 我想要这样
Example 1
Example 2
我查看了这个来源：
Get mouse possition (Whosebug)
Java 2d rotation in direction mouse point (Whosebug)
Rotating an object to point towards the mouse
问题是 MouseInfo.getPointerInfo().getLocation(); returns 绝对鼠标位置。您需要相对于您的游戏的鼠标位置 canvas。你可以修改你的gameclass中的render方法如下：
Point mouseLocation = MouseInfo.getPointerInfo().getLocation();
SwingUtilities.convertPointFromScreen(mouseLocation, this);
handler.render(g, mouseLocation);
这需要您相应地修改渲染方法的方法签名。这只是将游戏 canvas 中的 mouseLocation 传递给玩家渲染方法的一种方法。
在播放器的渲染方法中使用 mouseLocation 而不是 MouseInfo.getPointerInfo().getLocation();。
为了将玩家置于 canvas 的中心并使他围绕他的中心旋转，您还需要进行一些更改：
- 您应该设置游戏大小 canvas 而不是 window(
JFrame)。为此，请在游戏 canvas 上调用setPreferredSize(new Dimension(width, height));并在frame.setVisible(true)之前调用frame.pack()。这将确保您的游戏 canvas 具有WIDTH和HEIGHT. 指定的大小
- 您可以将两个字段
refx和refy添加到您的GameObjectclass 来描述您的GameObject的参考点（例如它的中心） .然后，您可以通过调用new Player(WIDTH/2-16, HEIGHT/2-16, 16, 16, ID.Player, handler)来构造一个新的Player，玩家的初始位置位于 (WIDTH/2-16,HEIGHT/2-16) 及其参考点是 (16,16) - 当玩家由 32x32 矩形表示时玩家的中心。 - 在 Player 的渲染方法中，用
int centerX = Math.round(x + refx); int centerY = Math.round(y + refy);初始化你想要旋转的中心，其中 (x,y) 是你想要旋转的对象的位置和 (refx, refy) 你想要的点相对于对象的位置旋转（例如 x =WIDTH/2-16，y =HEIGTH/2-16，refx = 16，refy = 16）。