The code creates a JFrame with a JPanel onto which it draws an image loaded from a file. The objective is to make a rectangular area of the picture, such as for example the red square, appear darker than the rest. I'm assuming this may involve taking a subimage of the image, looping through an array of pixels, scaling them, and then painting that subimage onto the JPanel, but I don't know how to do this using the Java API.
package SpriteEditor_Tests;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;
public class ImageTestApp extends JFrame
{
public BufferedImage image;
int x1 = 50;
int x2 = 100;
int y1 = 50;
int y2 = 100;
public static void main (String [] args)
{
new ImageTestApp();
}
public ImageTestApp()
{
setTitle("Image Test App");
try
{
image = ImageIO.read(new File("C:/Users/Paul/Desktop/derp.png"));
}
catch (IOException io)
{
System.out.println("IO caught"); System.exit(0);
}
setSize(500,500);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
add(new ImageDisplay());
}
class ImageDisplay extends JPanel
{
public void paintComponent(Graphics g)
{
g.drawImage(image, -100, -100, getWidth(), getHeight(), Color.RED, null);
g.setColor(Color.RED);
g.drawRect(x1, y1, Math.abs(x2 - x1), Math.abs(y2 - y1));
}
}
}
A "simple" solution would be to just create a new instance of Color with the desired alpha applied to it and fill the area you want darkened.
This is great if you have a color you want to use, but when I want to use a predefined color, it's not as simple. Instead, I prefer to use an AlphaComposite as it gives me some advantages.
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage background;
public TestPane() {
try {
background = ImageIO.read(getClass().getResource("/images/background.jpg"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
public Dimension getPreferredSize() {
if (background == null) {
return new Dimension(200, 200);
}
return new Dimension(background.getWidth(), background.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background == null) {
return;
}
Graphics2D g2d = (Graphics2D) g.create();
g2d.drawImage(background, 0, 0, this);
int x = (getWidth() - 100) / 2;
int y = (getHeight() - 100) / 2;
Rectangle rect = new Rectangle(x, y, 200, 200);
g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.5f));
g2d.fill(rect);
g2d.dispose();
g2d = (Graphics2D) g.create();
g2d.setColor(Color.RED);
g2d.drawRect(x, y, 200, 200);
g2d.dispose();
}
}
}
Now, if want to generate a new image with the are darkened, you can follow the same basic concept, but instead of painting to the components Graphics context, you'd paint directly to the BufferedImages Graphics content. This is the wonderful power of the abstract nature of the Graphics API.
Don't forget, when you override a method, you are obliged to either over take ALL of its responsibilities or call its super implementation.
paintComponent does some basic, but important work and you should make sure to call super.paintComponent before you start performing your custom painting, this will just reduce any possibility of issues.
Darken each pixel individually
Okay, if, instead, you want to darken each pixel in the rectangle individually, this becomes a "little" more complicated, but not hard.
After a lot of time and testing, I settled on using the follow algorithm to darken a given color. This will push the color towards "black" the more you darken it, which some algorithms don't do.
public static Color darken(Color color, double fraction) {
int red = (int) Math.round(Math.max(0, color.getRed() - 255 * fraction));
int green = (int) Math.round(Math.max(0, color.getGreen() - 255 * fraction));
int blue = (int) Math.round(Math.max(0, color.getBlue() - 255 * fraction));
int alpha = color.getAlpha();
return new Color(red, green, blue, alpha);
}
Then, all you have to do is get the the color of the pixel, darken it and reapply.
For this example, I actually use a separate sub image, but you can do it directly to the parent image
BufferedImage subImage = background.getSubimage(x, y, 200, 200);
for (int row = 0; row < subImage.getHeight(); row++) {
for (int col = 0; col < subImage.getWidth(); col++) {
int packedPixel = subImage.getRGB(col, row);
Color color = new Color(packedPixel, true);
color = darken(color, 0.5);
subImage.setRGB(col, row, color.getRGB());
}
}
Now, before someone jumps down my throat, no, this is not the most performant approach, but it gets over messing about with "packed" pixel values (because I can never remember how to unpack those :P) and most of my API code is based around the use of Color anyway
Runnable example...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setVisible(true);
}
});
}
public static Color darken(Color color, double fraction) {
int red = (int) Math.round(Math.max(0, color.getRed() - 255 * fraction));
int green = (int) Math.round(Math.max(0, color.getGreen() - 255 * fraction));
int blue = (int) Math.round(Math.max(0, color.getBlue() - 255 * fraction));
int alpha = color.getAlpha();
return new Color(red, green, blue, alpha);
}
public class TestPane extends JPanel {
private BufferedImage background;
private BufferedImage darkended;
public TestPane() {
try {
background = ImageIO.read(getClass().getResource("/images/background.jpg"));
int x = (background.getWidth() - 100) / 2;
int y = (background.getHeight() - 100) / 2;
BufferedImage subImage = background.getSubimage(x, y, 200, 200);
for (int row = 0; row < subImage.getHeight(); row++) {
for (int col = 0; col < subImage.getWidth(); col++) {
int packedPixel = subImage.getRGB(col, row);
Color color = new Color(packedPixel, true);
color = darken(color, 0.5);
subImage.setRGB(col, row, color.getRGB());
}
}
darkended = subImage;
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
public Dimension getPreferredSize() {
if (background == null) {
return new Dimension(200, 200);
}
return new Dimension(background.getWidth(), background.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background == null) {
return;
}
Graphics2D g2d = (Graphics2D) g.create();
g2d.drawImage(background, 0, 0, this);
int x = (getWidth() - 100) / 2;
int y = (getHeight() - 100) / 2;
g2d.drawImage(darkended, x, y, this);
g2d.setColor(Color.RED);
g2d.drawRect(x, y, 200, 200);
g2d.dispose();
}
}
}
Related
I'm trying to make my own, very inefficient "image copier". I'm doing it by reading the pixels from the original image on to an array and then resetting those same pixels in my default BufferedImage. And then repaint the frame. Row by row.
I'm trying to repaint the frame every after each row of pixels has been stored in the array. But the frame only gets updated once; when it finishes storing the pixels.
My code is all over the place, and I'm probably doing a lot of stuff wrong. This is for an assignment and I've been going at it for a while now and would really appreciate some help.
Here is my code:
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;
import java.awt.*;
import javax.swing.JComponent;
import javax.swing.JFrame;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
public class pixelReloc extends JComponent {
static BufferedImage image,newImg;
static JFrame frame;
public void initialize() {
int width = getSize().width;
int height = getSize().height;
int pixels[];
int index = 0;
int j=0,i=0;
File f = new File("/path/to/file/images/shrek4life.jpg");
try{
image = ImageIO.read(f);
}catch(IOException e){}
System.out.println("checkpoint 1");
image = createResizedCopy(image,500,500,true);
newImg = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_RGB);
pixels = new int[(image.getWidth()) * (image.getHeight())];
System.out.println("checkpoint 2");
for(i= 0; i < newImg.getWidth(); i++){
for(j = 0; j < newImg.getHeight(); j++){
//get the rgb color of the old image
Color c = new Color(image.getRGB(i, j));
int r = c.getRed();
int g = c.getGreen();
int b = c.getBlue();
pixels[index++] = (r<<16) | (g<<8) | b;
}
newImg.setRGB(0, 0, i, j, pixels, 0, 0);
frame.getContentPane().validate();
frame.getContentPane().repaint();
}
System.out.println("checkpoint 4");
//image.setRGB(0, 0, width, height, data, 0, width);
}
public BufferedImage createResizedCopy(BufferedImage originalImage,
int scaledWidth, int scaledHeight,
boolean preserveAlpha)
{
System.out.println("resizing...");
int imageType = preserveAlpha ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB;
BufferedImage scaledBI = new BufferedImage(scaledWidth, scaledHeight, imageType);
Graphics2D g = scaledBI.createGraphics();
if (preserveAlpha) {
g.setComposite(AlphaComposite.Src);
}
g.drawImage(originalImage, 0, 0, scaledWidth, scaledHeight, null);
g.dispose();
return scaledBI;
}
public void paint(Graphics g) {
if (image == null)
initialize();
g.drawImage(newImg, 0, 0, this);
}
public static void main(String[] args) {
frame = new JFrame("P I X E L S");
frame.getContentPane().add(new pixelReloc ());
frame.setSize(500, 500);
frame.setLocation(100, 100);
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
frame.setVisible(true);
}
}
Here is the picture I'm reading the pixels from:
and this is how it's coming out:
The program doesn't give any errors or anything.
The basic answer to your question is, you're blocking the Event Dispatching Thread.
Swing is both single threaded and NOT thread safe. This means you can't run long running or blocking operations from within the EDT AND you should't not update the UI or some state the UI depends on from outside the EDT.
I recommend that you start by having a look at Concurrency in Swing.
This leaves with three basic options:
Use another Thread. This is problematic as you need to ensure that any state that the UI relies on is only updated from within the context of the EDT
Use a SwingWorker. This is basically the previous option, but with built in management which allows you to publish updates which are process'ed on the EDT
Use a Swing Timer. In your case, this is probably not the best solution, but it is the simplest.
For example
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.SwingWorker;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
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.add(new PixelReloc());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class Pixel {
private int x, y;
private int color;
public Pixel(int x, int y, int color) {
this.x = x;
this.y = y;
this.color = color;
}
public int getX() {
return x;
}
public int getY() {
return y;
}
public int getColor() {
return color;
}
}
public class PixelReloc extends JComponent {
private BufferedImage image;
private BufferedImage newImg;
public PixelReloc() {
SwingWorker<Integer[], List<Pixel>> worker = new SwingWorker<Integer[], List<Pixel>>() {
Integer pixels[];
#Override
protected Integer[] doInBackground() throws Exception {
pixels = new Integer[image.getWidth() * image.getHeight()];
int index = 0;
List<Pixel> pixies = new ArrayList<>(image.getWidth());
for (int y = 0; y < image.getHeight(); y++) {
for (int x = 0; x < image.getWidth(); x++) {
int color = image.getRGB(x, y);
pixels[index++] = color;
pixies.add(new Pixel(x, y, color));
}
publish(new ArrayList<Pixel>(pixies));
pixies = new ArrayList<>(image.getWidth());
Thread.sleep(100);
}
return pixels;
}
#Override
protected void process(List<List<Pixel>> chunks) {
for (List<Pixel> pixels : chunks) {
for (Pixel pixel : pixels) {
newImg.setRGB(pixel.getX(), pixel.getY(), pixel.getColor());
}
}
repaint();
}
};
File f = new File("/Volumes/Big Fat Extension/Dropbox/MegaTokyo/chaotic_megatokyo_by_fredrin-d9k84so.jpg");
try {
image = ImageIO.read(f);
} catch (IOException e) {
}
System.out.println("checkpoint 1");
image = createResizedCopy(image, 200, 200, true);
newImg = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_ARGB);
worker.execute();
// pixels = new int[(image.getWidth()) * (image.getHeight())];
// System.out.println("checkpoint 2");
// for (i = 0; i < newImg.getWidth(); i++) {
// for (j = 0; j < newImg.getHeight(); j++) {
// //get the rgb color of the old image
// Color c = new Color(image.getRGB(i, j));
// int r = c.getRed();
// int g = c.getGreen();
// int b = c.getBlue();
// pixels[index++] = (r << 16) | (g << 8) | b;
// }
// }
// System.out.println("checkpoint 4");
//image.setRGB(0, 0, width, height, data, 0, width);
}
#Override
public Dimension getPreferredSize() {
return image == null ? new Dimension(200, 200) : new Dimension(image.getWidth(), image.getHeight());
}
public BufferedImage createResizedCopy(BufferedImage originalImage,
int scaledWidth, int scaledHeight,
boolean preserveAlpha) {
System.out.println("resizing...");
Image scaled = originalImage.getScaledInstance(scaledWidth, -1, Image.SCALE_SMOOTH);
BufferedImage scaledBI = new BufferedImage(scaled.getWidth(null), scaled.getHeight(null), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = scaledBI.createGraphics();
g.drawImage(scaled, 0, 0, null);
g.dispose();
return scaledBI;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(newImg, 0, 0, this);
}
}
}
The Thread.sleep in the SwingWorker is intended to do two things:
Give time for the EDT to process the results from the process call and
Slow down the worker so that the results can be updated on the UI.
In my testing without it, the image was pretty much updated instantly.
I also recommend you take the time to better understand the paint process in Swing, start by having a look at:
Performing Custom Painting
Painting in AWT and Swing
The scaling mechanism you were using (and the one I've implemented) aren't the best solutions. I recommend having look at:
Java: maintaining aspect ratio of JPanel background image
Quality of Image after resize very low -- Java
for some better ideas.
You made a couple of mistakes, the first one is using 0 as scansize which should be the width of the image, also in the same line you should use the width and height instead of i and j.
newImg.setRGB(0, 0, image.getWidth(), image.getHeight(), pixels, 0, image.getWidth());
There is one other mistake which I will let you find on your own, it should be obvious after you see the image with the above fixed line.
I Have 3 Questing Regarding My Code
1==> How to remove Selected Shape in my code; when i right click every shape is deleted,
2==> I TOTALLY don't know how to highlight the overlapped are
3==> right now when i click on my JPanel, shape drawn from the point where mouse clicked, where as it should be the in the center of the mouse pointer
Thanks In advance
actually i'm new to Java. this is my code,
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.Shape;
import javax.swing.JPanel;
import javax.swing.JButton;
import Delete.Selection;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Area;
import java.util.ArrayList;
public class MyPanel extends JPanel {
ArrayList<MyRect> list = new ArrayList<MyRect>();
public MyPanel() {
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if(e.getButton() == MouseEvent.BUTTON1) {
MyRect r = new MyRect(e.getX(), e.getY());
list.add(r);
repaint();
}
else {
list.clear();
repaint();
}
}
}
);
setPreferredSize(new Dimension(600, 400));
setBackground(Color.CYAN);
}
public void paintComponent(Graphics g){
super.paintComponent(g);
for (int i = 0; i < list.size(); i++) {
MyRect r = list.get(i);
g.fillRect(r.x, r.y, r.w, r.h);
}
}
class MyRect {
int x, y, w=100, h=100;
Color c = Color.BLACK;
public MyRect(int x, int y, int w, int h, Color color) {
this.x = x;
this.y = y;
this.w = w;
this.h = h;
this.c = color;
}
public MyRect(int x, int y) {
this.x = x;
this.y = y;
}
}}
how to highlight the overlapped area
You can use the intersection(...) method of the Rectangle class to get a Rectangle to paint:
import java.awt.*;
import javax.swing.*;
import java.awt.geom.*;
public class IntersectingRectangles extends JPanel
{
#Override
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
Dimension d = getSize();
int width = d.width * 3 / 4;
int height = d.height * 3 / 4;
Rectangle r1 = new Rectangle(0, 0, width, height);
g2d.setColor( Color.BLUE );
g2d.fill( r1 );
Rectangle r2 = new Rectangle(d.width - width, d.height - height, width, height);
g2d.setColor( Color.YELLOW );
g2d.fill( r2 );
// Specific solution when using Rectangles only
Rectangle r3 = r1.intersection(r2);
g2d.setColor(Color.GREEN);
g2d.fill(r3);
/*
// For a more generic solution using any Shape
Area area = new Area(r1);
area.intersect( new Area(r2) );
g2d.setColor(Color.GREEN);
g2d.fill(area);
*/
g2d.dispose();
}
#Override
public Dimension getPreferredSize()
{
return new Dimension(300, 300);
}
private static void createAndShowGUI()
{
JFrame frame = new JFrame("Intersecting Rectangles");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new IntersectingRectangles());
frame.setLocationByPlatform( true );
frame.pack();
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
}
}
How to remove Selected Shape in my code; when i right click every shape is deleted,
You need to iterate through the ArrayList containing the Rectangles. Then you can use the Rectangle.contains( yourMousePoint ) method to determine which Rectangle you clicked on. You will need to save the reference to the Rectangle. Then when the loop finishes executing you can remove the Rectangle from the ArrayList.
shape drawn from the point where mouse clicked, where as it should be the in the center of the mouse pointer
Then you need to change the x/y location of the Rectangle. It should be:
int x = mousePoint.x - (width / 2);
int y = mousePoint.y - (height / 2);
where width/height represent the size of the Rectangle you want to draw.
I want to create a graphics whereby circles are overlapped and their colour fades out, also the circles should have a white space in between each other, something similar to this:
Here is how far I've got:
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import java.awt.event.MouseListener;
import java.awt.event.MouseEvent;
class Circles extends JPanel implements MouseListener {
public void mouseReleased(MouseEvent event) {
}
public void mousePressed(MouseEvent event) {
}
public void mouseClicked(MouseEvent event) {
}
public void mouseEntered(MouseEvent event) {}
public void mouseExited(MouseEvent event) {}
public Circles() {
addMouseListener(this);
}
public void paint(Graphics g) {
g.setColor(Color.white);
int w = getWidth();
int h = getHeight();
g.fillRect(0, 0, w, h);
Graphics2D g2 = (Graphics2D) g;
for (int i = 0; i < 20; i++) {
if (i % 2 == 0) {
Color c = new Color(255 - i * 10, 255 - i * 10, 255 - i * 10);
g2.setColor(c);
} else {
g2.setColor(Color.white);
}
g2.fillOval((5 * i), (5 * i), (w - 10) * i, (h - 10) * i);
}
}
public static void main(String[] args) {
Frame w = new Frame();
w.setVisible(true);
}
}
Frame:
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
public class Frame extends JFrame {
Circles myPanel;
public static void main(String[] args) {
Frame w = new Frame();
w.setVisible(true);
}
public Frame() {
setTitle("In-class Test 1: Starting Code");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(500, 220);
setLocation(300, 300);
myPanel = new Circles();
add(myPanel);
}
}
There are a number of ways to achieve this, but first, start by overriding paintComponent instead of paint.
Second, you will need some kind of loop that expand the radius of the circle on each iteration.
Thirdly, you will want a simple int value that acts as a alpha value, starting from 255 and decreases down to the faintest alpha level you want, perhaps 64 of example.
On each iteration of the loop, you will want to increase the radius value and decrease the alpha value accordingly. You would then simply need to create a new Color object with the RGB & alpha values you need
Check out 2D Graphics for details
Updated with example...
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
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;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class FadingCircles {
public static void main(String[] args) {
new FadingCircles();
}
public FadingCircles() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public static class TestPane extends JPanel {
public static final int CIRCLE_COUNT = 10;
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setRenderingHint(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHint(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_ENABLE);
g2d.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_PURE);
int maxRadius = Math.min(getWidth(), getHeight());
int alpha = 255;
int range = 255 - 32;
g2d.setStroke(new BasicStroke(6, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
for (int index = 0; index < CIRCLE_COUNT; index++) {
float progress = (float) index / (float) CIRCLE_COUNT;
alpha = 255 - Math.round(range * progress);
Color color = new Color(0, 0, 0, alpha);
g2d.setColor(color);
int radius = Math.round(maxRadius * progress);
int x = (getWidth() - radius) / 2;
int y = (getHeight() - radius) / 2;
g2d.draw(new Ellipse2D.Float(x, y, radius, radius));
}
g2d.dispose();
}
}
}
You might also like to check out Performing Custom Painting
I'm using Java Graphics and I keep getting "ugly" circles.
Here's what my Java program makes
And here's the same thing being made in Matlab
I think it is clear that the Java one is not as "nice" looking as the Matlab one, particularly on the edges of the circle. Note that this has nothing to do with the resolution...these images are practically the same size. Also note that I am already setting rendering hints.
Here's a stand alone with a Main function you can run to test this out.
package test;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
public class SimplePaint02 {
private static final int LINE_THICKNESS = 4;
private static final int LINE_GAP = 10;
private Color lineColor = Color.red;
public static void main(String[] args) {
new SimplePaint02();
}
public SimplePaint02() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
#Override
public Dimension getPreferredSize() {
return new Dimension(100, 100);
}
#Override
public void paintComponent(Graphics g) {
int radius = 50;
BufferedImage buffer = new BufferedImage(radius, radius, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = buffer.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION,RenderingHints.VALUE_INTERPOLATION_BILINEAR);
Ellipse2D circle = new Ellipse2D.Float(0, 0, radius,radius);
Shape clip = g2d.getClip();
g2d.setClip(circle);
AffineTransform at = g2d.getTransform();
g2d.setTransform(AffineTransform.getRotateInstance(Math.toRadians(45),radius / 2, radius / 2));
int gap = LINE_GAP;
g2d.setColor(Color.WHITE);
g2d.fill(circle);
g2d.setColor(lineColor);
//g2d.setStroke(new BasicStroke(LINE_THICKNESS));
for (int index = 0; index < 10; index++) {
int x1 = index*gap-(LINE_THICKNESS/2);
int y1 = 0;
int x2 = index*gap+(LINE_THICKNESS/2);
int y2 = radius;
int width = x2 - x1;
int height = y2 - y1;
g2d.fillRect(x1, y1, width, height);
//g2d.drawLine(index * gap, 0, index * gap, getRadius());
}
g2d.setTransform(at);
g2d.setClip(clip);
g2d.dispose();
g.drawImage(buffer, 0, 0, this);
}
}
}
EDIT: Please see Code Guy's answer below for a solution. This is marked correct because it was Joey Rohan who figured it out initially!
I got smooth edge when i tried out same thing:
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
public class DrawSmoothCircle {
public static void main(String[] argv) throws Exception {
BufferedImage bufferedImage = new BufferedImage(100, 100, BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = bufferedImage.createGraphics();
g2d.setRenderingHint (RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setPaint(Color.green);
g2d.fillOval(10, 10, 50, 50);
g2d.dispose();
ImageIO.write(bufferedImage, "png", new File("e:\\newimage.png"));
}
}
UPDATE:
After searching alot:
There is nothing wrong with the code but,
Well, unfortunately Java 2D (or at least Sun's current implementation) does not support "soft clipping."
But Also got a trick for the clips:
Follow This link,you can achieve what you are asking for.
(Also, i got a smooth edge, cause i din't use clip stuff,in my above image)
Here was the answer. I adapted the majority of the code from this site. Take a look:
Here's the code:
public void paintComponent(Graphics g) {
// Create a translucent intermediate image in which we can perform
// the soft clipping
GraphicsConfiguration gc = ((Graphics2D) g).getDeviceConfiguration();
BufferedImage img = gc.createCompatibleImage(getWidth(), getHeight(), Transparency.TRANSLUCENT);
Graphics2D g2 = img.createGraphics();
// Clear the image so all pixels have zero alpha
g2.setComposite(AlphaComposite.Clear);
g2.fillRect(0, 0, getWidth(), getHeight());
// Render our clip shape into the image. Note that we enable
// antialiasing to achieve the soft clipping effect. Try
// commenting out the line that enables antialiasing, and
// you will see that you end up with the usual hard clipping.
g2.setComposite(AlphaComposite.Src);
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(Color.WHITE);
g2.fillOval(0, 0, getRadius(), getRadius());
// Here's the trick... We use SrcAtop, which effectively uses the
// alpha value as a coverage value for each pixel stored in the
// destination. For the areas outside our clip shape, the destination
// alpha will be zero, so nothing is rendered in those areas. For
// the areas inside our clip shape, the destination alpha will be fully
// opaque, so the full color is rendered. At the edges, the original
// antialiasing is carried over to give us the desired soft clipping
// effect.
g2.setComposite(AlphaComposite.SrcAtop);
g2.setColor(lineColor);
int gap = LINE_GAP;
AffineTransform at = g2.getTransform();
g2.setTransform(AffineTransform.getRotateInstance(Math.toRadians(45),getRadius() / 2, getRadius() / 2));
for (int index = 0; index < 10; index++) {
int x1 = index*gap-(LINE_THICKNESS/2);
int y1 = 0;
int x2 = index*gap+(LINE_THICKNESS/2);
int y2 = getRadius();
int width = x2 - x1;
int height = y2 - y1;
g2.fillRect(x1, y1, width, height);
}
g2.setTransform(at);
g2.dispose();
// Copy our intermediate image to the screen
g.drawImage(img, 0, 0, null);
}
Update
OK. Then the idea is to not use clipping at all but instead to make the clipped shape by subtracting areas from each other.
import java.awt.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class SimplePaint02 {
private static final int LINE_THICKNESS = 4;
private static final int LINE_GAP = 10;
private Color lineColor = Color.red;
public static void main(String[] args) {
new SimplePaint02();
}
public SimplePaint02() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
int radius = 75;
#Override
public Dimension getPreferredSize() {
return new Dimension(radius, radius);
}
#Override
public void paintComponent(Graphics g) {
Ellipse2D circle = new Ellipse2D.Float(0, 0, radius, radius);
Area lines = new Area();
int gap = LINE_GAP;
for (int index = 0; index < 10; index++) {
int x1 = index * gap - (LINE_THICKNESS / 2);
int y1 = 0;
int x2 = index * gap + (LINE_THICKNESS / 2);
int y2 = radius;
int width = x2 - x1;
int height = y2 - y1;
Shape lineShape = new Rectangle2D.Double(x1, y1, width, height);
lines.add(new Area(lineShape));
//g3d.fillRect(x1, y1, width, height);
//g2d.drawLine(index * gap, 0, index * gap, getRadius());
}
//g2d.setClip(circle);
Area circleNoLines = new Area(circle);
circleNoLines.subtract(lines);
Area linesCutToCircle = new Area(circle);
linesCutToCircle.subtract(circleNoLines);
//g2d.setTransform(at);
BufferedImage buffer = new BufferedImage(radius * 2, radius * 2, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = buffer.createGraphics();
RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setTransform(AffineTransform.getRotateInstance(Math.toRadians(45), radius / 2, radius / 2));
g2d.setRenderingHints(rh);
g2d.setColor(Color.ORANGE);
g2d.fill(linesCutToCircle);
g2d.setColor(Color.RED);
g2d.fill(circleNoLines);
g2d.dispose();
g.drawImage(buffer, 0, 0, this);
}
}
}
Old code
Part of the problem is that the rendering operations typically do not apply to a Clip, though they will apply to the Shape when it is drawn. I generally solve that by (last) painting the Shape itself. E.G.
A 1.5 pixel BasicStroke is used here for the red circle - smoothing the rough edges produced by the Clip.
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
public class SimplePaint02 {
private static final int LINE_THICKNESS = 4;
private static final int LINE_GAP = 10;
private Color lineColor = Color.red;
public static void main(String[] args) {
new SimplePaint02();
}
public SimplePaint02() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
int radius = 75;
#Override
public Dimension getPreferredSize() {
return new Dimension((int)(1.1*radius), (int)(1.1*radius));
}
#Override
public void paintComponent(Graphics g) {
BufferedImage buffer = new BufferedImage(radius*2, radius*2, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = buffer.createGraphics();
RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
rh.put(RenderingHints.KEY_DITHERING,RenderingHints.VALUE_DITHER_ENABLE);
rh.put(RenderingHints.KEY_COLOR_RENDERING,RenderingHints.VALUE_COLOR_RENDER_QUALITY);
g2d.setRenderingHints(rh);
Ellipse2D circle = new Ellipse2D.Float(0, 0, radius,radius);
Shape clip = g2d.getClip();
g2d.setClip(circle);
AffineTransform at = g2d.getTransform();
g2d.setTransform(AffineTransform.getRotateInstance(Math.toRadians(45),radius / 2, radius / 2));
int gap = LINE_GAP;
g2d.setColor(Color.WHITE);
g2d.fill(circle);
g2d.setColor(lineColor);
//g2d.setStroke(new BasicStroke(LINE_THICKNESS));
for (int index = 0; index < 10; index++) {
int x1 = index*gap-(LINE_THICKNESS/2);
int y1 = 0;
int x2 = index*gap+(LINE_THICKNESS/2);
int y2 = radius;
int width = x2 - x1;
int height = y2 - y1;
g2d.fillRect(x1, y1, width, height);
//g2d.drawLine(index * gap, 0, index * gap, getRadius());
}
g2d.setTransform(at);
g2d.setClip(clip);
g2d.setClip(null);
g2d.setStroke(new BasicStroke(1.5f));
g2d.draw(circle);
g2d.dispose();
g.drawImage(buffer, 0, 0, this);
}
}
}
I used drawPolygon method to draw circle by generating array of most of the points on circumference of circle with proposed radius.
Code:
import java.awt.*;
import java.applet.*;
/*<applet code="OnlyCircle" width=500 height=500>
</applet>*/
public class OnlyCircle extends Applet{
public void paint(Graphics g){
int r=200;//radius
int x1=250;//center x coordinate
int y1=250;//center y coordinate
double x2,y2;
double a=0;
double pi=3.14159;
int count=0;
int i=0;
int f=0;
int[] x22=new int[628319];
int[] y22=new int[628319];
while(a<=2*pi&&i<628319&&f<628319)
{
double k=Math.cos(a);
double l=Math.sin(a);
x2=x1+r*k;
y2=y1+r*l;
x22[i]=(int)x2;
y22[f]=(int)y2;
i++;
f++;
a+=0.00001;
}
int length=x22.length;
g.drawPolygon(x22,y22,length);
}
}
You can enable anti-aliasing:
Graphics2D g2 = (Graphics2D) g;
Map<RenderingHints.Key, Object> hints = new HashMap<RenderingHints.Key, Object>();
hints.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setRenderingHints(hints);
I also suggest you draw to the Graphics object you get from the paintComponent method rather than creating an intermediate BufferedImage.
I want to draw a PARTIALLY transparent image on top of another (Making shadows over things). I am currently using java's Graphics2D class to render, I've been told to set the composite to AlphaComposite, but that only sets it completely transparent.
Can I do this with my current setup? What do I have to do to fix this?
This is the code I was told that would make it partially transparent:
AlphaComposite ac = java.awt.AlphaComposite.getInstance(AlphaComposite.CLEAR, 0.5F);
g.setComposite(ac);
(I am using png images by the way)
Heres your sscce (these are all in different classes but i put them together for simplicity) (I use an image called "Test" in the local folder "Images", you can use whatever for this as long as it is a png Image named the same
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.DisplayMode;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Window;
import javax.swing.ImageIcon;
import com.blazingkin.atrox.ScreenManager;
public class AtroxAdventrum{
public static void main(String[] args) {
new AtroxAdventrum().run();
}
private static DisplayMode modes[] = {
//new DisplayMode(1080,720,32,0),
//new DisplayMode(1080,720,24,0),
//new DisplayMode(1080,720,16,0),
//new DisplayMode(1440,900,32,0),
//new DisplayMode(1440,900,24,0),
//new DisplayMode(1440,900,16,0),
};
private boolean running = true;
public ScreenManager s;
public void stop(){
running = false;
}
public void run(){
try{
init();
gameLoop();
}finally{
s.restoreScreen();
}
}
public void init(){
s = new ScreenManager();
DisplayMode dm = s.findFirstCompatibleMode(modes);
s.setFullScreen(dm);
Window w = s.getFullScreenWindow();
w.setFont(new Font("Arial", Font.PLAIN, 20));
w.setBackground(Color.black);
w.setForeground(Color.white);
}
public void gameLoop(){
long startTime = System.currentTimeMillis();
long cumTime = startTime;
while (running)
{
long timePassed = System.currentTimeMillis() - cumTime;
cumTime += timePassed;
if (limitfps){
try{
Thread.sleep(15);
}catch(Exception e){}
}
update(timePassed);
Graphics2D g = s.getGraphics();
draw(g);
g.dispose();
s.update();
}
}
public void update(long timePassed){
}
public boolean limitfps = false;
public void draw(Graphics2D g){
g.clearRect(0, 0, s.getWidth(), s.getHeight());
AlphaComposite ac = java.awt.AlphaComposite.getInstance(AlphaComposite.CLEAR,0.5F);
g.setComposite(ac);
g.drawImage(new ImageIcon("Images/Test.png").getImage(), 30, 30, 30, 30, null);
}
}
If you run this you will have to alt + tab out and end the process (as it doesnt have anything in this portion of code to do such)
You're using the wrong rule -- don't use AlphaComposite.CLEAR.
The AlphaComposite API states this about CLEAR:
Both the color and the alpha of the destination are cleared (Porter-Duff Clear rule). Neither the source nor the destination is used as input.
So this will make the image disappear. Experiment with other rules. While you were creating your SSCCE, I created mine. See what happens when you comment out the one rule line for the other. For example change this
// int rule = AlphaComposite.CLEAR;
int rule = AlphaComposite.SRC_OVER;
to this:
int rule = AlphaComposite.CLEAR;
// int rule = AlphaComposite.SRC_OVER;
The whole SSCCE:
import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Composite;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Stroke;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class TestAlphaComposite extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private static final Stroke BASIC_STROKE = new BasicStroke(6f);
BufferedImage backgroundImage;
BufferedImage overlayImage;
public TestAlphaComposite() {
backgroundImage = createBackGroundImage();
overlayImage = createOverlayImage();
}
private BufferedImage createBackGroundImage() {
BufferedImage img = new BufferedImage(PREF_W, PREF_H,
BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(BASIC_STROKE);
g2.setColor(Color.blue);
int circleCount = 10;
for (int i = 0; i < circleCount ; i++) {
int x = (i * PREF_W) / (2 * circleCount);
int y = x;
int w = PREF_W - 2 * x;
int h = w;
g2.drawOval(x, y, w, h);
}
g2.dispose();
return img;
}
private BufferedImage createOverlayImage() {
BufferedImage img = new BufferedImage(PREF_W, PREF_H,
BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(BASIC_STROKE);
g2.setColor(Color.red);
int circleCount = 10;
for (int i = 0; i < circleCount + 1; i++) {
int x1 = (i * PREF_W) / (circleCount);
int y1 = 0;
int x2 = PREF_W - x1;
int y2 = PREF_H;
float alpha = (float)i / circleCount;
if (alpha > 1f) {
alpha = 1f;
}
// int rule = AlphaComposite.CLEAR;
int rule = AlphaComposite.SRC_OVER;
Composite comp = AlphaComposite.getInstance(rule , alpha );
g2.setComposite(comp );
g2.drawLine(x1, y1, x2, y2);
}
g2.dispose();
return img;
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (backgroundImage != null) {
g.drawImage(backgroundImage, 0, 0, null);
}
if (overlayImage != null) {
g.drawImage(overlayImage, 0, 0, null);
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("TestAlphaComposite");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new TestAlphaComposite());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
By the way, your SSCCE isn't a true SSCCE. There's no way that any of us can compile or run that code as it has dependencies that we don't have access to, namely "com.blazingkin.atrox.ScreenManager". If you need our help in the future, you'll want to write better complying sscce's.