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# 形状和填充 > 原文: [https://zetcode.com/gfx/java2d/shapesandfills/](https://zetcode.com/gfx/java2d/shapesandfills/) 在 Java 2D 教程的这一部分中,我们创建一些基本的和更高级的形状。 我们用纯色,渐变和纹理填充形状。 ## 基本形状 首先,我们绘制一些基本的 Java 2D 形状。 `BasicShapes.java` ```java package com.zetcode; import java.awt.Color; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.Ellipse2D; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { private void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g; g2d.setPaint(new Color(150, 150, 150)); RenderingHints rh = new RenderingHints( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); g2d.setRenderingHints(rh); g2d.fillRect(30, 20, 50, 50); g2d.fillRect(120, 20, 90, 60); g2d.fillRoundRect(250, 20, 70, 60, 25, 25); g2d.fill(new Ellipse2D.Double(10, 100, 80, 100)); g2d.fillArc(120, 130, 110, 100, 5, 150); g2d.fillOval(270, 130, 50, 50); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class BasicShapesEx extends JFrame { public BasicShapesEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Basic shapes"); setSize(350, 250); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { BasicShapesEx ex = new BasicShapesEx(); ex.setVisible(true); } }); } } ``` 在此示例中,我们在面板上绘制了六个基本形状:正方形,矩形,圆角矩形,椭圆形,弧形和圆形。 ```java g2d.setPaint(new Color(150, 150, 150)); ``` 形状将以灰色背景绘制。 ```java g2d.fillRect(20, 20, 50, 50); g2d.fillRect(120, 20, 90, 60); ``` `fillRect()`方法用于绘制矩形和正方形。 前两个参数是要绘制的形状的 x,y 坐标。 最后两个参数是形状的宽度和高度。 ```java g2d.fillRoundRect(250, 20, 70, 60, 25, 25); ``` 在这里,我们创建一个圆角矩形。 最后两个参数是四个角处圆弧的水平和垂直直径。 ```java g2d.fill(new Ellipse2D.Double(10, 100, 80, 100)); ``` `fill()`方法绘制给定形状的内部-椭圆。 ```java g2d.fillArc(120, 130, 110, 100, 5, 150); ``` `fillArc()`方法填充覆盖指定矩形的圆弧或椭圆弧。 圆弧是圆的圆周的一部分。 ```java g2d.fillOval(270, 130, 50, 50); ``` 使用`fillOval()`方法绘制一个圆。 ![Basic shapes](https://img.kancloud.cn/43/ad/43ad144750a36518f1b44c5affba7c03_350x250.jpg) 图:基本形状 ## 一般路径 可以使用`GeneralPath`构造更复杂的形状。 它代表由直线,二次贝塞尔曲线和三次贝塞尔曲线构成的几何路径。 下面的示例使用此类创建星形。 `StarEx.java` ```java package com.zetcode; import java.awt.Color; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.GeneralPath; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { private final double points[][] = { { 0, 85 }, { 75, 75 }, { 100, 10 }, { 125, 75 }, { 200, 85 }, { 150, 125 }, { 160, 190 }, { 100, 150 }, { 40, 190 }, { 50, 125 }, { 0, 85 } }; private void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g.create(); g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); g2d.setPaint(Color.gray); g2d.translate(25, 5); GeneralPath star = new GeneralPath(); star.moveTo(points[0][0], points[0][1]); for (int k = 1; k < points.length; k++) star.lineTo(points[k][0], points[k][1]); star.closePath(); g2d.fill(star); g2d.dispose(); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class StarEx extends JFrame { public StarEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Star"); setSize(350, 250); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { StarEx ex = new StarEx(); ex.setVisible(true); } }); } } ``` 我们从一系列角度创造一颗星星。 ```java private final double points[][] = { { 0, 85 }, { 75, 75 }, { 100, 10 }, { 125, 75 }, { 200, 85 }, { 150, 125 }, { 160, 190 }, { 100, 150 }, { 40, 190 }, { 50, 125 }, { 0, 85 } }; ``` 这些是星星的坐标。 ```java GeneralPath star = new GeneralPath(); ``` 在这里,我们实例化了`GeneralPath`类。 ```java star.moveTo(points[0][0], points[0][1]); ``` 我们移到`GeneralPath`的初始坐标。 ```java for (int k = 1; k < points.length; k++) star.lineTo(points[k][0], points[k][1]); ``` 在这里,我们连接星的所有坐标。 ```java star.closePath(); g2d.fill(star); ``` 我们封闭路径并填充星星内部。 ![Star](https://img.kancloud.cn/03/72/037276a598339c924926e7ca55bc92ae_350x250.jpg) 图:星星 ## 区域 创建复杂形状的另一种方法是组成区域。 `Area`存储和操纵二维空间的封闭区域的与分辨率无关的描述。 可以通过加,减,交,异或运算来操纵它。 `AreasEx.java` ```java package com.zetcode; import java.awt.Color; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.Area; import java.awt.geom.Ellipse2D; import java.awt.geom.Rectangle2D; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { public void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g; RenderingHints rh = new RenderingHints( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); g2d.setRenderingHints(rh); g2d.setPaint(Color.gray); Area a1 = new Area(new Rectangle2D.Double(20, 20, 100, 100)); Area a2 = new Area(new Ellipse2D.Double(50, 50, 100, 100)); a1.subtract(a2); g2d.fill(a1); Area a3 = new Area(new Rectangle2D.Double(150, 20, 100, 100)); Area a4 = new Area(new Ellipse2D.Double(150, 20, 100, 100)); a3.subtract(a4); g2d.fill(a3); Area a5 = new Area(new Rectangle2D.Double(280, 20, 100, 100)); Area a6 = new Area(new Ellipse2D.Double(320, 40, 100, 100)); a5.add(a6); g2d.fill(a5); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class AreasEx extends JFrame { public AreasEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Areas"); setSize(450, 200); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { AreasEx ex = new AreasEx(); ex.setVisible(true); } }); } } ``` 该示例通过操纵区域来创建三种不同的形状。 ```java Area a1 = new Area(new Rectangle2D.Double(20, 20, 100, 100)); Area a2 = new Area(new Ellipse2D.Double(50, 50, 100, 100)); a1.subtract(a2); g2d.fill(a1); ``` 此代码通过从矩形中减去椭圆来构造形状。 ```java Area a5 = new Area(new Rectangle2D.Double(280, 20, 100, 100)); Area a6 = new Area(new Ellipse2D.Double(320, 40, 100, 100)); a5.add(a6); g2d.fill(a5); ``` 这些线通过在椭圆上添加矩形来构造形状。 ![Areas](https://img.kancloud.cn/d7/8f/d78f6a10acbcf381514f2e395cd26a3d_450x200.jpg) 图:区域 ## 色彩 `Color`类用于处理 Java 2D 中的颜色。 要使用当前颜色填充矩形,我们使用`fillRect()`方法。 `ColoursEx.java` ```java package com.zetcode; import java.awt.Color; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { public void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g; g2d.setColor(new Color(125, 167, 116)); g2d.fillRect(10, 10, 90, 60); g2d.setColor(new Color(42, 179, 231)); g2d.fillRect(130, 10, 90, 60); g2d.setColor(new Color(70, 67, 123)); g2d.fillRect(250, 10, 90, 60); g2d.setColor(new Color(130, 100, 84)); g2d.fillRect(10, 100, 90, 60); g2d.setColor(new Color(252, 211, 61)); g2d.fillRect(130, 100, 90, 60); g2d.setColor(new Color(241, 98, 69)); g2d.fillRect(250, 100, 90, 60); g2d.setColor(new Color(217, 146, 54)); g2d.fillRect(10, 190, 90, 60); g2d.setColor(new Color(63, 121, 186)); g2d.fillRect(130, 190, 90, 60); g2d.setColor(new Color(31, 21, 1)); g2d.fillRect(250, 190, 90, 60); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class ColoursEx extends JFrame { public ColoursEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Colours"); setSize(360, 300); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { ColoursEx ex = new ColoursEx(); ex.setVisible(true); } }); } } ``` 在示例中,我们绘制了九个彩色矩形。 ```java Graphics2D g2d = (Graphics2D) g; ``` 更改图形上下文的`color`属性时,无需创建`Graphics2D`类的副本或重置该值。 ```java g2d.setColor(new Color(125, 167, 116)); ``` 使用`Color`类创建新的颜色。 构造器的参数是新颜色的红色,绿色和蓝色部分。 `setColor()`方法将图形上下文的当前颜色设置为指定的颜色值。 所有后续图形操作均使用此颜色值。 ```java g2d.fillRect(10, 15, 90, 60); ``` 为了用颜色填充矩形,我们使用`fillRect()`方法。 ![Colours](https://img.kancloud.cn/09/66/0966d8781a02045ecd50bc16a556f8e2_360x300.jpg) 图:颜色 ## 渐变 在计算机图形学中,渐变是从浅到深或从一种颜色到另一种颜色的阴影的平滑混合。 在 2D 绘图程序和绘画程序中,渐变用于创建彩色背景和特殊效果以及模拟灯光和阴影。 (answers.com) `GradientsEx.java` ```java package com.zetcode; import java.awt.Color; import java.awt.EventQueue; import java.awt.GradientPaint; import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { private void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g.create(); GradientPaint gp1 = new GradientPaint(5, 5, Color.red, 20, 20, Color.black, true); g2d.setPaint(gp1); g2d.fillRect(20, 20, 300, 40); GradientPaint gp2 = new GradientPaint(5, 25, Color.yellow, 20, 2, Color.black, true); g2d.setPaint(gp2); g2d.fillRect(20, 80, 300, 40); GradientPaint gp3 = new GradientPaint(5, 25, Color.green, 2, 2, Color.black, true); g2d.setPaint(gp3); g2d.fillRect(20, 140, 300, 40); GradientPaint gp4 = new GradientPaint(25, 25, Color.blue, 15, 25, Color.black, true); g2d.setPaint(gp4); g2d.fillRect(20, 200, 300, 40); GradientPaint gp5 = new GradientPaint(0, 0, Color.orange, 0, 20, Color.black, true); g2d.setPaint(gp5); g2d.fillRect(20, 260, 300, 40); g2d.dispose(); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class GradientsEx extends JFrame { public GradientsEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Gradients"); setSize(350, 350); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { GradientsEx ex = new GradientsEx(); ex.setVisible(true); } }); } } ``` 我们的代码示例展示了五个带有渐变的矩形。 ```java GradientPaint gp4 = new GradientPaint(25, 25, Color.blue, 15, 25, Color.black, true); ``` 要使用渐变,我们使用`GradientPaint`类。 通过操纵颜色值以及起点和终点,我们可以获得不同的结果。 ```java g2d.setPaint(gp4); ``` 通过调用`setPaint()`方法激活渐变。 ![Gradients](https://img.kancloud.cn/f5/d4/f5d40e20673d5314b0c8f4cd1e049d33_350x350.jpg) 图:渐变 ## 纹理 纹理是应用于形状的位图图像。 要在 Java 2D 中使用纹理,我们使用`TexturePaint`类。 通过`setPaint()`方法应用纹理。 `TexturesEx.java` ```java package com.zetcode; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Rectangle; import java.awt.TexturePaint; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; import javax.imageio.ImageIO; import javax.swing.JFrame; import javax.swing.JPanel; class Surface extends JPanel { private BufferedImage slate; private BufferedImage java; private BufferedImage pane; private TexturePaint slatetp; private TexturePaint javatp; private TexturePaint panetp; public Surface() { loadImages(); } private void loadImages() { try { slate = ImageIO.read(new File("slate.png")); java = ImageIO.read(new File("java.png")); pane = ImageIO.read(new File("pane.png")); } catch (IOException ex) { Logger.getLogger(Surface.class.getName()).log( Level.SEVERE, null, ex); } } private void doDrawing(Graphics g) { Graphics2D g2d = (Graphics2D) g.create(); slatetp = new TexturePaint(slate, new Rectangle(0, 0, 90, 60)); javatp = new TexturePaint(java, new Rectangle(0, 0, 90, 60)); panetp = new TexturePaint(pane, new Rectangle(0, 0, 90, 60)); g2d.setPaint(slatetp); g2d.fillRect(10, 15, 90, 60); g2d.setPaint(javatp); g2d.fillRect(130, 15, 90, 60); g2d.setPaint(panetp); g2d.fillRect(250, 15, 90, 60); g2d.dispose(); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); doDrawing(g); } } public class TexturesEx extends JFrame { public TexturesEx() { initUI(); } private void initUI() { add(new Surface()); setTitle("Textures"); setSize(360, 120); setLocationRelativeTo(null); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { TexturesEx ex = new TexturesEx(); ex.setVisible(true); } }); } } ``` 在代码示例中,我们用三个不同的纹理填充三个矩形。 ```java slate = ImageIO.read(new File("slate.png")); ``` 使用`ImageIO`类,我们将图像读取到缓冲图像中。 ```java slatetp = new TexturePaint(slate, new Rectangle(0, 0, 90, 60)); ``` 我们从缓冲图像中创建一个`TexturePaint`类。 ```java g2d.setPaint(slatetp); g2d.fillRect(10, 15, 90, 60); ``` 我们用纹理填充矩形。 ![Textures](https://img.kancloud.cn/f4/5c/f45cf55dbb66c69fa323e314e4a18784_360x120.jpg) 图:纹理 在 Java 2D 教程的这一部分中,我们介绍了 Java 2D 库的一些基本形状和更高级的形状。