java-2d

I need to draw a ring, with given thickness, that looks something like this: The center must be transparent, so that it doesn't cover previously drawn shapes. (or other rings) I've tried something like this: //g is a Graphics2D object g.setColor(Color.RED); g.drawOval(x,y,width,height); g.setColor(Color.WHITE); g.drawOval(x+thickness,y+thickness,width-2*thickness,height-2*thickness); which draws a satisfactory ring, but it covers other shapes; the interior is white, not transparent. How can I modify/rewrite my code so that it doesn't do that? You can create an Area from an Ellipse2D that

I've been playing with animation in Swing on Java 8 and have encountered some strange behaviour: sometimes content of a component suddenly becomes stale after calling repaint() on some other unrelated component. Below is the code, which reproduces this behaviour for me: import javax.swing.*; import java.awt.*; import java.awt.event.MouseEvent; import java.awt.event.MouseAdapter; public class Crosshair extends JPanel { private int currentMouseX = 0; private int currentMouseY = 0; public Crosshair() { addMouseMotionListener(new MouseAdapter() { @Override public void mouseMoved(MouseEvent e) {

Closed. This question is off-topic . It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 3 years ago . I'm supposed to develop a Java game using AWT. I'm stuck with the concept of "collision detection". If you can help me with any tutorials that explain the concept (how it works) or give examples (source code), I'd be grateful. ins0m A strong tutorial on 2d collision detection can be found at metanetsoftware (makes of N) The authors write about the theoretical fundamentals and the challenges. They give you some

I am drawing Java 2D stuff like this: g2.translate( getWidth() / 2, getHeight() / 2 ); g2.rotate( angle ); g2.draw( new Ellipse2D.Double( -1, -1, 1, 1 ) ); Now I want to kow the coordinates of the ellipse on my sceen. Any idea how to get it? So I need the conversion from logical to physical space. Get the AffineTransform from the Graphics2D object and use the transform(src, dst) method to go to screen coordinates (you can do this for any point). If you want the path of the ellipse you can use Ellipse2D.getPathIterator(AffineTransform at) - it returns a PathIterator . This example gets the