Swing components have no width or height until they’ve been rendered. This occurs if you call pack() or setVisible(true) on a root container. Consider placing your x y int initialization code in the componentResized method of a ComponentListener that is added to your JPanel. e.g., import java.awt.event.*; import java.awt.*; import javax.swing.*; public class TestLinePanel { … Read more
Have them draw directly in a BufferedImage by way of it’s Graphics2D object which you can get via getGraphics(). Then use ImageIO.write(…) to output the image to whatever file type you desire (and that’s supported). The ImageIO API should help you with this: ImageIO API. The other issue you’ll have is where are they supposed … Read more
This is a relatively simple concept (no offense). To start with, don’t mix your code with JApplet and JFrame. If you want to use your application in these two mediums, separate the logic into a separate component (like JPanel) which you can easily add to either. You really shouldn’t add a top level container to … Read more
Precedence matters… In your second example, you’re apply a rotation AFTER you’ve drawn everything. This is not how graphics works. You need to apply the transformation first, then everything that follows will use that transformation. public class TestRotateImage { public static void main(String[] args) { new TestRotateImage(); } public TestRotateImage() { EventQueue.invokeLater(new Runnable() { @Override … Read more
The order of your transformation matters. Basically your example code is saying “rotate the image by 90 degrees AND then translate it….” So, using your code (rotate, then translate) produces… Switching the order (translate then rotate) produces … import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; import java.awt.image.BufferedImage; import java.io.File; import … Read more
As always, the Internet to the rescue. So, this is some code which I hobbled together from other resources/post/blogs which will return a new image which is sized so it will contain the rotated image public BufferedImage rotateImageByDegrees(BufferedImage img, double angle) { double rads = Math.toRadians(angle); double sin = Math.abs(Math.sin(rads)), cos = Math.abs(Math.cos(rads)); int w … Read more
The drawString method does not handle new-lines. You’ll have to split the string on new-line characters yourself and draw the lines one by one with a proper vertical offset: void drawString(Graphics g, String text, int x, int y) { for (String line : text.split(“\n”)) g.drawString(line, x, y += g.getFontMetrics().getHeight()); } Here is a complete example … Read more
Have a look through this source which behaves in a more predictable manner, and also includes a nice tweak to the chopper image (animated). 😉 import java.awt.*; import java.awt.event.*; import java.awt.geom.*; import java.awt.image.BufferedImage; import java.net.URL; import java.io.IOException; import javax.imageio.ImageIO; import javax.swing.*; public class MainFrame { public MainFrame() { JFrame f = new JFrame(“Helicopter Background Test”); … Read more
I would use a function similar to this: public void RotateRectangle(Graphics g, Rectangle r, float angle) { using (Matrix m = new Matrix()) { m.RotateAt(angle, new PointF(r.Left + (r.Width / 2), r.Top + (r.Height / 2))); g.Transform = m; g.DrawRectangle(Pens.Black, r); g.ResetTransform(); } } It uses a matrix to perform the rotation at a certain … Read more
For images you have to use drawImage method of Graphics2D with the relative AffineTransform. For shape you can rotate Graphics2D itself: public void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2d = (Graphics2D)g; g2d.setColor(Color.WHITE); Rectangle rect2 = new Rectangle(100, 100, 20, 20); g2d.rotate(Math.toRadians(45)); g2d.draw(rect2); g2d.fill(rect2); } And btw, you should override paintComponent method instead of paint. Citing … Read more