Java版 桌面画图工具

package Cut; import java.awt.BasicStroke; import java.awt.Color; import java.awt.Dimension; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.GraphicsConfiguration; import java.awt.GraphicsDevice; import java.awt.GraphicsEnvironment; import java.awt.HeadlessException; import java.awt.Image; import java.awt.Toolkit; import java.awt.Transparency; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseMotionListener; import java.awt.event.MouseWheelEvent; import java.awt.image.BufferedImage; import javax.swing.ImageIcon; /** * 截屏窗体 用来监听鼠标移动 绘制图案 * * @author zzc * */ public class DrawListener extends MouseAdapter implements MouseMotionListener { // 画笔类型 颜色 int type; Color color; MyPanel panel; BufferedImage image; Graphics2D g; int x0, y0; // 屏幕中点坐标 int centerX, centerY; // 屏幕大小 int screenX, screenY; // 每次缩放的大小 int cutWidth, cutHeight; // 缩放程度 int degree = 0; public DrawListener(MyPanel panel, int type, Color color) { this.g = (Graphics2D) panel.getGraphics(); this.type = type; this.color = color; this.panel = panel; image = panel.icon; Dimension screensize = Toolkit.getDefaultToolkit().getScreenSize(); centerX = screensize.width / 2; centerY = screensize.height / 2; screenX = screensize.width; screenY = screensize.height; cutWidth = screensize.width; cutHeight = screensize.height; initdraw(); } // 初始化画笔 private void initdraw() { int size = 2; if (type == 1) size = 2; else if (type == 2) size = 5; else if (type == 3) { size = 17; } g.setStroke(new BasicStroke(size)); // 边界宽度为5 g.setColor(color); } @Override public void mouseDragged(MouseEvent e) { int x = e.getX(); int y = e.getY(); if (type == 3) { // double L2 = Math.pow(y - y0, 2) + Math.pow(x - x0, 2); // double L = Math.sqrt(L2); // double sinL = Math.abs(y - y0) / L; // double cosL = Math.abs(x - x0) / L; // int xL = (int) (20 * sinL); // int yL = (int) (20 * cosL); g.setColor(new Color(color.getRed(), color.getGreen(), color .getBlue(), 20)); } if (!e.isControlDown()) { g.drawLine(x0, y0, x, y); } else { // System.out.println(centerX + " " + centerY); centerX += x0 - x; centerY += y0 - y; limitCenterXY(); ImageIcon icon = cutBmp(); Image Image = icon.getImage(); BufferedImage bImage = toBufferedImage(Image); panel.setIcon(bImage); } x0 = x; y0 = y; } @Override public void mouseMoved(MouseEvent e) { // TODO Auto-generated method stub } @Override public void mousePressed(MouseEvent e) { super.mousePressed(e); x0 = e.getX(); y0 = e.getY(); } @Override public void mouseReleased(MouseEvent e) { // TODO Auto-generated method stub super.mouseReleased(e); } @Override public void mouseWheelMoved(MouseWheelEvent e) { // TODO Auto-generated method stub super.mouseWheelMoved(e); int t = e.getWheelRotation(); // System.out.println(t); ImageIcon icon; if (t < 0) { // 滚轮向上滑动 放大 中心坐标不变 degree++; } else { // 滑轮向下划 缩小 degree--; if (degree < 0) degree = 0; boolean a = limitCenterX(); boolean b = limitCenterY(); // 如果当截取区域未到边界 中心坐标不变 // 如果当截取区域已到边界 // 改变中心位置 防止扩大截取长宽后超出范围 if (a | b) { updateCenterXY(a,b); } } icon = cutBmp(); Image Image = icon.getImage(); BufferedImage bImage = toBufferedImage(Image); panel.setIcon(bImage); } // 图像放大 public ImageIcon cutBmp() { // 设置要截取宽高 setCutSize(); // 限制中心点坐标 limitCenterXY(); System.out.println("中点坐标：" + centerX + " " + centerY + "起点坐标：" + (centerX - cutWidth / 2) + " " + (centerY - cutHeight / 2) + " 长宽:" + cutWidth + " " + cutHeight); BufferedImage subimage = image.getSubimage(centerX - cutWidth / 2, centerY - cutHeight / 2,// 开始截取点的坐标 cutWidth, cutHeight);// 截取地图的大小 return new ImageIcon(subimage.getScaledInstance(screenX, screenY, BufferedImage.SCALE_DEFAULT));// 返回当前显示的地图 } // 设置要截取宽高 public void setCutSize() { float f = (float) (degree / 10.0) + 1; // System.out.println(f); // 要截取的长度 当degree越大截取的长宽越小 即放大 当degree越小截取的长宽越大 即缩小 cutWidth = (int) (screenX / f); cutHeight = (int) (screenY / f); } // 更新中心点坐标 r用来判断改变x 还是 y public void updateCenterXY(boolean a, boolean b) { // 得到为改变钱的截取长宽 int oldcutwidth = cutWidth; int oldcutheight = cutHeight; // 设置新截取长宽 setCutSize(); int tempx = (cutWidth - oldcutwidth) / 2; int tempy = (cutHeight - oldcutheight) / 2; if (a) { if (centerX < screenX / 2) { // 中心点向右移动 centerX += tempx; } else { // 中心点向左移动 centerX -= tempx; } } if (b) { if (centerY < screenX / 2) { // 中心点向下移动 centerY += tempy; } else { // 中心点向上移动 centerY -= tempy; } } limitCenterXY(); } // 限制中心点坐标 public void limitCenterXY() { limitCenterX(); limitCenterY(); } public boolean limitCenterX() { // 先判断 截取长宽能否被2整除 不能整除 要对中心坐标进行改变 int tempx = 0; if (cutWidth % 2 != 0) tempx = 1; // 到达边界返回true 未到 返回false if (centerX < cutWidth / 2.0) { centerX = cutWidth / 2 + tempx; return true; } else if (centerX > screenX - cutWidth / 2) { centerX = screenX - cutWidth / 2 - tempx; return true; } return false; } public boolean limitCenterY() { // 先判断 截取长宽能否被2整除 不能整除 要对中心坐标进行改变 int tempy = 0; if (cutHeight % 2 != 0) tempy = 1; // 到达边界返回true 未到 返回false if (centerY < cutHeight / 2) { centerY = cutHeight / 2 + tempy; return true; } else if (centerY > screenY - cutHeight / 2) { centerY = screenY - cutHeight / 2 - tempy; return true; } return false; } // 将 Image 转化为 BufferedImage public static BufferedImage toBufferedImage(Image image) { if (image instanceof BufferedImage) { return (BufferedImage) image; } // This code ensures that all the pixels in the image are loaded image = new ImageIcon(image).getImage(); // Determine if the image has transparent pixels; for this method's // implementation, see e661 Determining If an Image Has Transparent // Pixels // boolean hasAlpha = hasAlpha(image); // Create a buffered image with a format that's compatible with the // screen BufferedImage bimage = null; GraphicsEnvironment ge = GraphicsEnvironment .getLocalGraphicsEnvironment(); try { // Determine the type of transparency of the new buffered image int transparency = Transparency.OPAQUE; /* * if (hasAlpha) { transparency = Transparency.BITMASK; } */ // Create the buffered image GraphicsDevice gs = ge.getDefaultScreenDevice(); GraphicsConfiguration gc = gs.getDefaultConfiguration(); bimage = gc.createCompatibleImage(image.getWidth(null), image.getHeight(null), transparency); } catch (HeadlessException e) { // The system does not have a screen } if (bimage == null) { // Create a buffered image using the default color model int type = BufferedImage.TYPE_INT_RGB; // int type = BufferedImage.TYPE_3BYTE_BGR;//by wang /* * if (hasAlpha) { type = BufferedImage.TYPE_INT_ARGB; } */ bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), type); } // Copy image to buffered image Graphics g = bimage.createGraphics(); // Paint the image onto the buffered image g.drawImage(image, 0, 0, null); g.dispos