﻿ java – 将一个方块从起点移动到以固定速度点击鼠标的位置 - 代码日志

#### java – 将一个方块从起点移动到以固定速度点击鼠标的位置

``````           ________X ← the mouse click
/
/   ↑
/ ←  = movement path
/
/
_____/
|   | ← character
|___|
``````

(请不要批评我的代码太多)

`````` //int x and int y are the positions of the mouse, champion = the character

public static Champion calculateChampionMovement(int x, int y, Champion champion) {

if (x != champion.x || y != champion.y) {

//x and y dist = the distance between the character and the cursor
int xDist = x - champion.x;
int yDist = y - champion.y;

//the angle
plrAngle = Math.atan2(yDist, xDist) * 180 / Math.PI;

//the speed of the character on the x and y axis
//(character diagonally moves at the speed of "champion.speed")
plrXSpeed = champion.speed * Math.cos(plrAngle * Math.PI / 180);
plrYSpeed = champion.speed * Math.sin(plrAngle * Math.PI / 180);

//calls the method below that actually moves the character
playerMain.champion = (Champion) Entity.moveChampions(x, y, champion, champion.speed, plrXSpeed, plrYSpeed);

champion.moving = true;
}
return playerMain.champion;
}
``````

`````` //called by the method above
public static Entity moveChampions(int x, int y, Champion champion, float speed, double xSpeed, double ySpeed) {

//if the distance between the character on the x and y axis is not
//exactly divisible by "speed", then this helps the character stop.
if (Math.abs(x - champion.x) <= speed) {
champion.x = x;
}
if (Math.abs(y - champion.y) <= speed) {
champion.y = y;
}
//stops the character
if (x == champion.x && y == champion.y) {
champion.moving = false;
}
//moves the character
if (champion.moving) {
champion.x += xSpeed;
champion.y += ySpeed;
}
return champion;
}
``````

``````public static void buttonTest() {
if (RIGHTCLICK == true) {

//mouse x and y positions
cursorClickX = (int) (mapX + MOUSE_X);
cursorClickY = (int) (mapY + MOUSE_Y);

//first method (setup the x and y speed)
playerMain.champion = PlayerMain.testMainChampionMove(cursorClickX, cursorClickY, playerMain.champion);

// if character is already moving
} else if (playerMain.champion.moving == true) {
//move the character
playerMain.champion = (Champion) Entity.moveChampions(cursorClickX, cursorClickY, playerMain.champion, champAsdf.speed, plrXSpeed, plrYSpeed);
}
}
``````

>计算两点之间的距离
>在给定的持续时间内将对象移动一长行.

>起点
>终点

``````double distance = Math.sqrt(
(startX - targetX) * (startX - targetX)
+ (startY - targetY) * (startY - targetY));
``````

``````time = distance / speed
``````

``````long duration = System.currentTimeMillis() - startTime;
double progress = duration / runTime;
``````

``````double x = (int) (startX + ((targetX - startX) * progress));
double y = (int) (startY + ((targetY - startY) * progress));
``````

``````import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestMove {

public static void main(String[] args) {
new TestMove();
}

public TestMove() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}

JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}

public class TestPane extends JPanel {

private Rectangle champion;
private Line2D path;

private double speed = 0.1;

private Timer timer;
private Long startTime;

private double targetX, targetY;
private double startX, startY;
private double runTime;

public TestPane() {
champion = new Rectangle(95, 95, 10, 10);

@Override
public void mouseClicked(MouseEvent e) {
timer.stop();
calculateChampionMovement(e.getX(), e.getY(), champion);
startTime = System.currentTimeMillis();
timer.start();
}
});

timer = new Timer(40, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (targetX == champion.getCenterX() && targetY == champion.getCenterY()) {
System.out.println("Stopped as same");
timer.stop();
}

long duration = System.currentTimeMillis() - startTime;
double progress = duration / runTime;

if (progress >= 1.0) {
System.out.println("Stopped out of time");
progress = 1.0;
timer.stop();
}

double x = (int) (startX + ((targetX - startX) * progress));
double y = (int) (startY + ((targetY - startY) * progress));

// x/y are the center points, need to adjust them so the shape
// moves about the center point
champion.setRect(x - 5, y - 5, 10, 10);

repaint();
}
});
}

@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}

@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.draw(champion);
if (path != null) {
g2d.setColor(Color.RED);
g2d.draw(path);
}
g2d.dispose();
}

public void calculateChampionMovement(double x, double y, Rectangle champion) {

if (x != champion.getCenterX() || y != champion.getCenterY()) {

targetX = x;
targetY = y;

startX = champion.getCenterX();
startY = champion.getCenterY();

path = new Line2D.Double(
champion.getCenterX(),
champion.getCenterY(),
x, y);

double distance = Math.sqrt(
(startX - targetX) * (startX - targetX)
+ (startY - targetY) * (startY - targetY));

runTime = distance / (double)speed;

}
}
}

}
``````
https://stackoverflow.com/questions/31041991/moving-a-square-from-a-starting-point-to-the-position-of-a-mouse-click-at-a-fixe