Java Tutorial/2D Graphics/Line
Содержание
- 1 A line is drawn using two points
- 2 Compares two lines are returns true if they are equal or both null.
- 3 Creates a region surrounding a line segment by "widening" the line segment.
- 4 Dash style line
- 5 Draw a line
- 6 Draw a point: use a drawLine() method
- 7 Draw Dashed
- 8 draw Line from to
- 9 Line2D.Float
- 10 Line dashes style 2
- 11 Line Dash Style 4
- 12 Lines Dashes style 3
A line is drawn using two points
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LinesDashes1 extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
float[] dash1 = { 2f, 0f, 2f };
g2d.drawLine(20, 40, 250, 40);
BasicStroke bs1 = new BasicStroke(1,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_ROUND,
1.0f,
dash1,
2f);
g2d.setStroke(bs1);
g2d.drawLine(20, 80, 250, 80);
}
public static void main(String[] args) {
LinesDashes1 lines = new LinesDashes1();
JFrame frame = new JFrame("Lines");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(lines);
frame.setSize(280, 270);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Compares two lines are returns true if they are equal or both null.
import java.awt.geom.Line2D;
public class Main {
/**
* Compares two lines are returns <code>true</code> if they are equal or
* both <code>null</code>.
*
* @param l1 the first line (<code>null</code> permitted).
* @param l2 the second line (<code>null</code> permitted).
*
* @return A boolean.
*/
public static boolean equal(final Line2D l1, final Line2D l2) {
if (l1 == null) {
return (l2 == null);
}
if (l2 == null) {
return false;
}
if (!l1.getP1().equals(l2.getP1())) {
return false;
}
if (!l1.getP2().equals(l2.getP2())) {
return false;
}
return true;
}
}
Creates a region surrounding a line segment by "widening" the line segment.
/*
* JCommon : a free general purpose class library for the Java(tm) platform
*
*
* (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* -------------------
* ShapeUtilities.java
* -------------------
* (C)opyright 2003-2008, by Object Refinery Limited and Contributors.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*
* $Id: ShapeUtilities.java,v 1.18 2008/06/02 06:58:28 mungady Exp $
*
* Changes
* -------
* 13-Aug-2003 : Version 1 (DG);
* 16-Mar-2004 : Moved rotateShape() from RefineryUtilities.java to here (DG);
* 13-May-2004 : Added new shape creation methods (DG);
* 30-Sep-2004 : Added createLineRegion() method (DG);
* Moved drawRotatedShape() method from RefineryUtilities class
* to this class (DG);
* 04-Oct-2004 : Renamed ShapeUtils --> ShapeUtilities (DG);
* 26-Oct-2004 : Added a method to test the equality of two Line2D
* instances (DG);
* 10-Nov-2004 : Added new translateShape() and equal(Ellipse2D, Ellipse2D)
* methods (DG);
* 11-Nov-2004 : Renamed translateShape() --> createTranslatedShape() (DG);
* 07-Jan-2005 : Minor Javadoc fix (DG);
* 11-Jan-2005 : Removed deprecated code in preparation for 1.0.0 release (DG);
* 21-Jan-2005 : Modified return type of RectangleAnchor.coordinates()
* method (DG);
* 22-Feb-2005 : Added equality tests for Arc2D and GeneralPath (DG);
* 16-Mar-2005 : Fixed bug where equal(Shape, Shape) fails for two Polygon
* instances (DG);
* 01-Jun-2008 : Fixed bug in equal(GeneralPath, GeneralPath) method (DG);
*
*/
import java.awt.Shape;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
/**
* Utility methods for {@link Shape} objects.
*
* @author David Gilbert
*/
public class Main {
/**
* Creates a region surrounding a line segment by "widening" the line
* segment. A typical use for this method is the creation of a
* "clickable" region for a line that is displayed on-screen.
*
* @param line the line (<code>null</code> not permitted).
* @param width the width of the region.
*
* @return A region that surrounds the line.
*/
public static Shape createLineRegion(final Line2D line, final float width) {
final GeneralPath result = new GeneralPath();
final float x1 = (float) line.getX1();
final float x2 = (float) line.getX2();
final float y1 = (float) line.getY1();
final float y2 = (float) line.getY2();
if ((x2 - x1) != 0.0) {
final double theta = Math.atan((y2 - y1) / (x2 - x1));
final float dx = (float) Math.sin(theta) * width;
final float dy = (float) Math.cos(theta) * width;
result.moveTo(x1 - dx, y1 + dy);
result.lineTo(x1 + dx, y1 - dy);
result.lineTo(x2 + dx, y2 - dy);
result.lineTo(x2 - dx, y2 + dy);
result.closePath();
}
else {
// special case, vertical line
result.moveTo(x1 - width / 2.0f, y1);
result.lineTo(x1 + width / 2.0f, y1);
result.lineTo(x2 + width / 2.0f, y2);
result.lineTo(x2 - width / 2.0f, y2);
result.closePath();
}
return result;
}
}
Dash style line
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LinesDashes1 extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
float[] dash1 = { 2f, 0f, 2f };
g2d.drawLine(20, 40, 250, 40);
BasicStroke bs1 = new BasicStroke(1,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_ROUND,
1.0f,
dash1,
2f);
g2d.setStroke(bs1);
g2d.drawLine(20, 80, 250, 80);
}
public static void main(String[] args) {
LinesDashes1 lines = new LinesDashes1();
JFrame frame = new JFrame("Lines");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(lines);
frame.setSize(280, 270);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Draw a line
import java.awt.Graphics;
import javax.swing.JComponent;
import javax.swing.JFrame;
class MyCanvas extends JComponent {
public void paint(Graphics g) {
g.drawLine(20, 20, 200, 200);
}
}
public class DrawLine {
public static void main(String[] a) {
JFrame window = new JFrame();
window.setBounds(30, 30, 300, 300);
window.getContentPane().add(new MyCanvas());
window.setVisible(true);
}
}
Draw a point: use a drawLine() method
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Points extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.red);
for (int i = 0; i <= 100000; i++) {
Dimension size = getSize();
int w = size.width ;
int h = size.height;
Random r = new Random();
int x = Math.abs(r.nextInt()) % w;
int y = Math.abs(r.nextInt()) % h;
g2d.drawLine(x, y, x, y);
}
}
public static void main(String[] args) {
Points points = new Points();
JFrame frame = new JFrame("Points");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(points);
frame.setSize(250, 200);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Draw Dashed
/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Contact info: lobochief@users.sourceforge.net
*/
import java.awt.*;
public class GUITasks {
public static Frame getTopFrame() {
Frame[] frames = Frame.getFrames();
for(int i = 0; i < frames.length; i++) {
if(frames[i].getFocusOwner() != null) {
return frames[i];
}
}
if(frames.length > 0) {
return frames[0];
}
return null;
}
public static void drawDashed(Graphics g, int x1, int y1, int x2, int y2, int dashSize, int gapSize) {
if(x2 < x1) {
int temp = x1;
x1 = x2;
x2 = temp;
}
if(y2 < y1) {
int temp = y1;
y1 = y2;
y2 = temp;
}
int totalDash = dashSize + gapSize;
if(y1 == y2) {
int virtualStartX = (x1 / totalDash) * totalDash;
for(int x = virtualStartX; x < x2; x += totalDash) {
int topX = x + dashSize;
if(topX > x2) {
topX = x2;
}
int firstX = x;
if(firstX < x1) {
firstX = x1;
}
if(firstX < topX) {
g.drawLine(firstX, y1, topX, y1);
}
}
}
else if(x1 == x2) {
int virtualStartY = (y1 / totalDash) * totalDash;
for(int y = virtualStartY; y < y2; y += totalDash) {
int topY = y + dashSize;
if(topY > y2) {
topY = y2;
}
int firstY = y;
if(firstY < y1) {
firstY = y1;
}
if(firstY < topY) {
g.drawLine(x1, firstY, x1, topY);
}
}
}
else {
// Not supported
g.drawLine(x1, y1, x2, y2);
}
}
}
draw Line from to
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class MainClass extends JPanel {
public static void main(String[] a) {
JFrame f = new JFrame();
f.setSize(400, 400);
f.add(new MainClass());
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
public void paint(Graphics g) {
g.drawLine (10, 15, 100, 115);
}
}
Line2D.Float
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.geom.Line2D;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class SliderControlPaintLine extends JFrame {
DrawingCanvas canvas = new DrawingCanvas();
JSlider slider1, slider2, slider3, slider4, slider5, slider6, slider7, slider8;
double transX = 0.0;
double transY = 0.0;
double rotateTheta = 0.0;
double rotateX = 150.0;
double rotateY = 150.0;
double scaleX = 1.0;
double scaleY = 1.0;
float width = 1.0f;
public SliderControlPaintLine() {
JPanel controlPanel = new JPanel();
controlPanel.setLayout(new GridLayout(3, 3));
getContentPane().add(controlPanel, BorderLayout.NORTH);
JLabel label1 = new JLabel("Translate(dx,dy): ");
JLabel label2 = new JLabel("Rotate(Theta,ox,oy): ");
JLabel label3 = new JLabel("Scale(sx,sy)x10E-2:");
controlPanel.add(label1);
slider1 = createSlider(controlPanel, JSlider.HORIZONTAL, 0, 300, 150, 100, 50);
slider2 = createSlider(controlPanel, JSlider.HORIZONTAL, 0, 300, 150, 100, 50);
controlPanel.add(label2);
slider3 = createSlider(controlPanel, JSlider.HORIZONTAL, 0, 360, 0, 90, 45);
JPanel subPanel = new JPanel();
subPanel.setLayout(new GridLayout(1, 2));
slider4 = createSlider(subPanel, JSlider.HORIZONTAL, 0, 300, 150, 150, 50);
slider5 = createSlider(subPanel, JSlider.HORIZONTAL, 0, 300, 150, 150, 50);
controlPanel.add(subPanel);
controlPanel.add(label3);
slider6 = createSlider(controlPanel, JSlider.HORIZONTAL, 0, 200, 100, 100, 10);
slider7 = createSlider(controlPanel, JSlider.HORIZONTAL, 0, 200, 100, 100, 10);
JPanel widthPanel = new JPanel();
JLabel label4 = new JLabel("Width Control:", JLabel.RIGHT);
slider8 = createSlider(widthPanel, JSlider.HORIZONTAL, 0, 200, 100, 100, 10);
slider8.addChangeListener(new SliderListener());
widthPanel.setLayout(new GridLayout(1, 2));
widthPanel.add(label4);
widthPanel.add(slider8);
getContentPane().add(widthPanel, BorderLayout.SOUTH);
getContentPane().add(canvas);
setSize(500,500);
setVisible(true);
}
public static void main(String arg[]) {
new SliderControlPaintLine();
}
public JSlider createSlider(JPanel panel, int orientation, int minimumValue, int maximumValue,
int initValue, int majorTickSpacing, int minorTickSpacing) {
JSlider slider = new JSlider(orientation, minimumValue, maximumValue, initValue);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(majorTickSpacing);
slider.setMinorTickSpacing(minorTickSpacing);
slider.setPaintLabels(true);
slider.addChangeListener(new SliderListener());
panel.add(slider);
return slider;
}
class SliderListener implements ChangeListener {
public void stateChanged(ChangeEvent e) {
JSlider tempSlider = (JSlider) e.getSource();
if (tempSlider.equals(slider1)) {
transX = slider1.getValue() - 150.0;
canvas.repaint();
} else if (tempSlider.equals(slider2)) {
transY = slider2.getValue() - 150.0;
canvas.repaint();
} else if (tempSlider.equals(slider3)) {
rotateTheta = slider3.getValue() * Math.PI / 180;
canvas.repaint();
} else if (tempSlider.equals(slider4)) {
rotateX = slider4.getValue();
canvas.repaint();
} else if (tempSlider.equals(slider5)) {
rotateY = slider5.getValue();
canvas.repaint();
} else if (tempSlider.equals(slider6)) {
if (slider6.getValue() != 0.0) {
scaleX = slider6.getValue() / 100.0;
canvas.repaint();
}
} else if (tempSlider.equals(slider7)) {
if (slider7.getValue() != 0.0) {
scaleY = slider7.getValue() / 100.0;
canvas.repaint();
}
} else if (tempSlider.equals(slider8)) {
width = slider8.getValue();
canvas.repaint();
}
}
}
class DrawingCanvas extends Canvas {
public DrawingCanvas() {
setSize(300, 300);
}
public void paint(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.translate(transX, transY);
g2D.rotate(rotateTheta, rotateX, rotateY);
g2D.scale(scaleX, scaleY);
BasicStroke stroke = new BasicStroke(width);
g2D.setStroke(stroke);
Line2D line1 = new Line2D.Float(100f, 200f, 200f, 200f);
g2D.draw(line1);
}
}
}
Line dashes style 2
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LinesDashes2 extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.drawLine(20, 40, 250, 40);
float[] dash2 = { 1f, 1f, 1f };
BasicStroke bs2 = new BasicStroke(1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND, 1.0f, dash2,2f);
g2d.setStroke(bs2);
g2d.drawLine(20, 20, 250, 20);
}
public static void main(String[] args) {
LinesDashes2 lines = new LinesDashes2();
JFrame frame = new JFrame("Lines");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(lines);
frame.setSize(280, 270);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Line Dash Style 4
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LinesDashes4 extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
float[] dash4 = { 4f, 4f, 1f };
BasicStroke bs4 = new BasicStroke(1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND, 1.0f, dash4,
2f);
g2d.setStroke(bs4);
g2d.drawLine(20, 20, 250, 20);
}
public static void main(String[] args) {
LinesDashes4 lines = new LinesDashes4();
JFrame frame = new JFrame("Lines");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(lines);
frame.setSize(280, 270);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Lines Dashes style 3
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class LinesDashes3 extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
float[] dash3 = { 4f, 0f, 2f };
BasicStroke bs3 = new BasicStroke(1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_ROUND, 1.0f, dash3,
2f);
g2d.setStroke(bs3);
g2d.drawLine(20, 60, 250, 60);
}
public static void main(String[] args) {
LinesDashes3 lines = new LinesDashes3();
JFrame frame = new JFrame("Lines");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(lines);
frame.setSize(280, 270);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
