我正在学习2D图像。我们给了我们一个模板来使用，并告诉他们做各种事情。一切似乎都工作正常，除了已旋转绘制图像。我不懂为什么。这是图片。
public static int[][] letterN = {
{0, 1, 1, 1, 1, 1, 1, 1, 1, 0},
{0, 1, 1, 1, 1, 1, 1, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0},
{0, 1, 1, 0, 0, 0, 0, 1, 1, 0}};
这是程序中的代码：我不明白为什么图像旋转弹出。所有其他字母也都在旋转。
package cmsc325animate;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class CMSC325Animate extends JPanel {
// A counter that increases by one in each frame.
private int frameNumber;
// The time, in milliseconds, since the animation started.
private long elapsedTimeMillis;
// This is the measure of a pixel in the coordinate system
// set up by calling the applyLimits method. It can be used
// for setting line widths, for example.
private float pixelSize;
static int translateX = 0;
static int translateY = 0;
static double rotation = 0.0;
static double scaleX = 1.0;
static double scaleY = 1.0;
ImageTemplate myImages = new ImageTemplate();
BufferedImage tImage = myImages.getImage(ImageTemplate.letterT);
BufferedImage nImage = myImages.getImageN(ImageTemplate.letterN);
BufferedImage oImage = myImages.getImageO(ImageTemplate.letterO);
BufferedImage aImage = myImages.getImageA(ImageTemplate.letterA);
BufferedImage hImage = myImages.getImageH(ImageTemplate.letterH);
BufferedImage heartImage = myImages.getImageHeart(ImageTemplate.heart);
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
JFrame window;
window = new JFrame("Java Animation"); // The parameter shows in the window title bar.
final CMSC325Animate panel = new CMSC325Animate(); // The drawing area.
window.setContentPane(panel); // Show the panel in the window.
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // End program when window closes.
window.pack(); // Set window size based on the preferred sizes of its contents.
window.setResizable(false); // Don't let user resize window.
Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
window.setLocation( // Center window on screen.
(screen.width - window.getWidth()) / 2,
(screen.height - window.getHeight()) / 2);
Timer animationTimer; // A Timer that will emit events to drive the animation.
final long startTime = System.currentTimeMillis();
// Taken from AnimationStarter
// Modified to change timing and allow for recycling
animationTimer = new Timer(1600, new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
if (panel.frameNumber > 4) {
panel.frameNumber = 0;
} else {
panel.frameNumber++;
}
panel.elapsedTimeMillis = System.currentTimeMillis() - startTime;
panel.repaint();
}
});
window.setVisible(true); // Open the window, making it visible on the screen.
animationTimer.start(); // Start the animation running.
}
public CMSC325Animate() {
// Size of Frame
setPreferredSize(new Dimension(800, 600));
}
// This is where all of the action takes place
// Code taken from AnimationStarter.java but modified to add the specific Images
// Also added looping structure for Different transformations
protected void paintComponent(Graphics g) {
/* First, create a Graphics2D drawing context for drawing on the panel.
* (g.create() makes a copy of g, which will draw to the same place as g,
* but changes to the returned copy will not affect the original.)
*/
Graphics2D g2 = (Graphics2D) g.create();
/* Turn on antialiasing in this graphics context, for better drawing.
*/
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
/* Fill in the entire drawing area with white.
*/
g2.setPaint(Color.WHITE);
g2.fillRect(0, 0, getWidth(), getHeight()); // From the old graphics API!
/* Here, I set up a new coordinate system on the drawing area, by calling
* the applyLimits() method that is defined below. Without this call, I
* would be using regular pixel coordinates. This function sets the value
* of the global variable pixelSize, which I need for stroke widths in the
* transformed coordinate system.
*/
// Controls your zoom and area you are looking at
applyWindowToViewportTransformation(g2, -75, 75, -75, 75, true);
AffineTransform savedTransform = g2.getTransform();
System.out.println("Frame is " + frameNumber);
switch (frameNumber) {
case 1: // First frame is unmodified.
translateX = 0;
translateY = 0;
scaleX = 1.0;
scaleY = 1.0;
rotation = 0;
break;
case 2: // Second frame translates each image by (-10, 12).
translateX = -10;
translateY = 12;
break;
case 3: // Third frame rotates each image by 55 degrees Counter
translateX = -10;
translateY = 12;
rotation = 55 * Math.PI / 180.0;
break;
// Can add more cases as needed
case 4: // 4th frame rotates each image by 75 degress Clockwise
translateX = -10;
translateY = 12;
rotation = 55 * Math.PI / 180.0;
rotation = 75 * Math.PI * 180;
break;
case 5: // Scales image 3.5 for x and 1.5 for y
translateX = -10;
translateY = 12;
rotation = 55 * Math.PI / 180.0;
rotation = 75 * Math.PI * 180;
scaleX = scaleX * 3.5;
scaleY = scaleY * 1.5;
break;
default:
break;
} // End switch
g2.translate(translateX, translateY); // Move image.
// To offset translate again
g2.translate(-10,10);
g2.rotate(rotation); // Rotate image.
g2.scale(scaleX, scaleY); // Scale image.
g2.drawImage(tImage, 100, 0, this); // Draw image.
g2.setTransform(savedTransform);
// draw nImage
g2.translate(translateX, translateY); // Move image.
// To offset translate again
// This allows you to place your images across your graphic
g2.translate(-30, 30);
g2.rotate(rotation); // Rotate image.
g2.scale(scaleX, scaleY); // Scale image.
g2.drawImage(nImage, 0, 0, this); // Draw image.
g2.setTransform(savedTransform);
// You can add more shapes/images as needed
// draw o Image
g2.translate(translateX, translateY); //move image
g2.translate(-10, 10);
g2.rotate(rotation);
g2.scale(scaleX, scaleY);
g2.drawImage(oImage, 0, 0, this);
g2.setTransform(savedTransform);
g2.translate(translateX, translateY); //move image
g2.translate(10, -10);
g2.rotate(rotation);
g2.scale(scaleX, scaleY);
g2.drawImage(aImage, 0, 0, this);
g2.setTransform(savedTransform);
g2.translate(translateX, translateY); //move image
g2.translate(30, -30);
g2.rotate(rotation);
g2.scale(scaleX, scaleY);
g2.drawImage(hImage, 0, 0, this);
g2.setTransform(savedTransform);
g2.translate(translateX, translateY); //move image
g2.translate(50, -50);
g2.rotate(rotation);
g2.scale(scaleX, scaleY);
g2.drawImage(heartImage, 0, 0, this);
g2.setTransform(savedTransform);
}
// Method taken directly from AnimationStarter.java Code
private void applyWindowToViewportTransformation(Graphics2D g2,
double left, double right, double bottom, double top,
boolean preserveAspect) {
int width = getWidth(); // The width of this drawing area, in pixels.
int height = getHeight(); // The height of this drawing area, in pixels.
if (preserveAspect) {
// Adjust the limits to match the aspect ratio of the drawing area.
double displayAspect = Math.abs((double) height / width);
double requestedAspect = Math.abs((bottom - top) / (right - left));
if (displayAspect > requestedAspect) {
// Expand the viewport vertically.
double excess = (bottom - top) * (displayAspect / requestedAspect - 1);
bottom += excess / 2;
top -= excess / 2;
} else if (displayAspect < requestedAspect) {
// Expand the viewport vertically.
double excess = (right - left) * (requestedAspect / displayAspect - 1);
right += excess / 2;
left -= excess / 2;
}
}
g2.scale(width / (right - left), height / (bottom - top));
g2.translate(-left, -top);
double pixelWidth = Math.abs((right - left) / width);
double pixelHeight = Math.abs((bottom - top) / height);
pixelSize = (float) Math.max(pixelWidth, pixelHeight);
}
}