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Swing layering - transparent component ignores underlying AWT element

First, to get it out of the way, I absolutely NEED to use heavyweight AWT component with a swing application. I need features from both of them.
The task is simple - render a heavyweight AWT Canvas (or any other element), render OpenGL scene directly onto it, then display Swing buttons above it for the UI.
My problem is that it works half-way.
I don't seem to have problems with Z-ordering. I am using jLayeredPanes for it, and I can move Canvas between layers and it actually works, popping on top or below other elements.
The problems are with transparency.
The thing is, Swing elements have Opaque parameter, and when it's set to false (non-opaque) - it should basically be transparent and you should see the next element below it. In my case, however, the AWT Canvas gets ignored, and you instead only see the next underlying SWING element.
Here are a couple of screenshots. They are taken from a standalone test project of mine. The canvas is stretched to the size of the frame, and in the upper left there is a JLayeredPane dummy element that is a simplified version of the menu.
On the first screenshot, the JLayeredPane's Opaque setting is set to true, and you can see that it's background property is set to Blue color.
On the second screenshot, everything is exactly the same but Opaque is set to false. Instead of displaying whatever is on the Canvas - what gets drawn in empty grey jFrame background.
Lastly, on the third screenshot I have put Canvas into a jPanel instead of leaving it on its own. As you can see, the Panel's orange color is seen through the transparent jLayeredPane, but the Canvas is yet again hidden.
Here's the code for the Frame layout. I would not post my rendering/context code right now
frame = new JFrame("AWT test");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.setPreferredSize(new Dimension(width, height));
canvas = new Canvas();
canvas.setSize(width,height);
//this part exists only in the third example
JPanel p = new JPanel();
p.setSize(width,height);
p.setBackground(Color.orange);
p.add(canvas);
// third example end
JLayeredPane pane = new JLayeredPane();
JLayeredPane paneMenu = new JLayeredPane();
JButton button = new JButton();
button.setSize(20,20);
paneMenu.setSize(200,200);
paneMenu.add(button, new Integer(1));
paneMenu.setBackground(Color.BLUE);
paneMenu.setOpaque(false); //True for the first example
pane.add(p, new Integer(1)); // canvas for the first two examples
pane.add(paneMenu, new Integer(2));
pane.setOpaque(false);
frame.add(pane);
frame.pack();
frame.setVisible(true);
frame.transferFocus();
Could anyone please explain me what is going on and how to do what I need to do.
I will repeat again - I have to use heavyweight component as render target. I am aware of solutions like JOGL's GLPanel which is a lightweight Swing-compatible component. But I tried that method and the performance is really slow, because instead of directly rendering onto it as a context target - it reads FrameBuffer from memory, flips it, and then paints it as BufferedImage. This path is not fitting for the limited resources of an embedded system that I'll be running on.
c0der said: Please post minimal reproducible example
Errrrm.... Didn't I?
Here, you can have it in complete java class form if you want, but I literally changed some variables for constants.
import javax.swing.*;
import java.awt.*;
public class Main
{
public static void main(String[] args)
{
JFrame frame = new JFrame("AWT test");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.setPreferredSize(new Dimension(500, 500));
Canvas canvas = new Canvas();
canvas.setSize(500,500);
canvas.setBackground(Color.RED);
//this part exists only in the third example
JPanel p = new JPanel();
p.setSize(500,500);
p.setBackground(Color.orange);
p.add(canvas);
// third example end
JLayeredPane pane = new JLayeredPane();
JLayeredPane paneMenu = new JLayeredPane();
JButton button = new JButton();
button.setSize(20,20);
paneMenu.setSize(200,200);
paneMenu.add(button, new Integer(1));
paneMenu.setBackground(Color.BLUE);
paneMenu.setOpaque(false); //True for the first example
pane.add(p, new Integer(1)); // canvas for the first two examples
pane.add(paneMenu, new Integer(2));
pane.setOpaque(false);
frame.add(pane);
frame.pack();
frame.setVisible(true);
frame.transferFocus();
}
}
A little update:
I initially suspected that because Swing elements delegate all their drawing to the underlying heavyweight element (In my case JFrame), then what happens is that the frame generates a single frameBuffer for itself and then displays on top of Canvas. Canvas itself is not handled in this generation and thus the frame "covers" over the canvas.
That doesn't seem to be the case. I tried making the JFrame undecorated, all panels non-opaque, and display the picture. The result - canvas is still "cut", and through the hole you can see the underlying IDE menu.
This makes me think that somewhere during Drawing, the Canvas itself detects that it is obscured by another element, and that it doesn't need to draw that area. So it "optimizes" itself and doesn't update these pixels.
Maybe I'm wrong. But here's another screenshot. This is the same example as before, but I took out 3d rendering and simply trying to display Canvas with background set to Red.

Once again, going to reply to my own question.
It turned out that I need to do
setComponentMixingCutoutShape(paneMenu, new Rectangle());
for the menu pane that lies underneath the button. That essentially tells java not to cut out the element from the heavyweight underlying component.

Is there a different way to draw on a JPanel?

So, I have been having trouble drawing multiple objects on a JFrame, and I know I need to use Layout managers, so I decided to test it with one object before I do multiple, however when I run this code:
fps = 30;
panel = new JPanel();
frame = new JFrame();
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.setSize(400,400);
frame.addKeyListener(new key());
running = true;
update = true;
ball = new Ball(0,0,1);
//panel.setBackground(Color.BLACK);
panel.add(ball);
panel.setVisible(true);
frame.add(panel, BorderLayout.CENTER);
frame.requestFocus();
frame.setVisible(true);
startTime = System.currentTimeMillis();
nothing draws (There is more to the code, i just didnt want to inlcude all of it). However, when I remove the comment and set the background to black, the JFrame turns black. So why is it that it wont draw my Ball object (which i know works) but will change the background? Is there a specific way you need to draw on a JPanel?

panel = new JPanel();
By default a JPanel uses a FlowLayout which respects the size of any component you add to the panel.
ball = new Ball(0,0,1);
I have no idea what the code in your Ball class looks like, but I would guess the preferred size is (0, 0).
You need to override the getPreferredSize() method of your Ball class to return the size of the Ball so that your layout manager can do its job.
Read the section from the Swing tutorial on Custom Painting for more information and working examples.
I know I need to use Layout managers,
The problem with a layout manager in this case is that the layout manager will control the position of the Ball which may or may not be what you want. If you want balls in random positions, then you will need to use a null layout. Then you will need to use the setSize() and setLocation() methods to control each Ball component.
Another option is to do custom painting of all your Balls. In this case you would add an object that you want to paint to an ArrayList. Then the custom painting code would iterate through the object in the list and paint them individually. See Playing With Shapes for ideas on this approach.

JPanel Format Problems

I have a 2 JPanels, 1 a button Panel and one a Graphic Panel. I would like the button panel to situated right below the graphic panel but the button panel cuts off the Graphics Panel in the middle. I've been trying the box layout which seems from discussions seems like the best format for what I am trying to do. Can anyone please give me some advice on my formatting problem.
JFrame canvas = new JFrame("Baseball Strike K");
JFrame canvas = new JFrame ("GraphicBoard");
canvas.setVisible(true);
canvas.setSize(1000,1000);
canvas.setDefaultCloseOperation(EXIT_ON_CLOSE);
//create two panels
//add them to contentPane
//set Layout
JPanel buttonPanel = createButtons();
JPanel mainPanel = new Graphic(); //extends JPanel and writes the paint method
mainPanel.setSize(1000, 1000);
Container content = canvas.getContentPane();
content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
content.add(mainPanel);
content.add(buttonPanel);

mainPanel.setSize(1000, 1000);
The job of the layout manager is to determine the size of the component, so you would never invoke the setSize() method of a components.
Instead you give hints to the layout manager on what the size should be. You would do this by overriding the getPreferredSize() method to return an appropriate value. Also, I would pick a more reasonable size (1000, 1000) is a little big to display on most screens. If you really want your painting area this large then I would add the paint panel to a JScrollPane and then add the scrollpane to the frame.
Try getting your code to work using a BoxLayout. Then I would suggest a better layout manager would be to use a BorderLayout. Then you add the paint panel to the CENTER and the buttons to the SOUTH. Now as you resize the frame the paint panel will be adjusted in size.
canvas.setVisible(true);
Also, the placement of that line of code is wrong. You should add all your components to the frame first, before making the frame visible.

Resize JPanel within JScrollPane - never smaller than viewport

I've created a JPanel and JScrollPane like so:
JPanel panel = new JPanel();
panel.setPreferredSize(5000, 5000);
JScrollPane scrollPane = new JScrollPane(panel, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPanel.getViewport().setBackground(Color.GRAY); //panel is white
I will be using event handlers to dynamically resize the panel. The problem is, sometimes the panel is smaller than the viewport. I'd set the panel's size like this:
panel.setPreferredSize(10, 10); //Just an example
but the panel will never be smaller than the viewport. I tried using
panel.setSize(10, 10);
and i saw a gray flicker (the viewport's background showing through), which indicated that the panel was being sized to what i wanted it to be, but then grew to the viewport's size. How can i stop this?

To control the sizing the view inside a JViewport, let it implement the Scrollable interface. Without, it's always forced to the size of the viewport.

Java: Adding panel inside another at run time to fit visible area

In my application I want to show generated graph, using JUNG. It produces JPanel object as output. So, i though it would be just a matter of adding a component to panel. But the graph is drawn outside of its parent panel. Screenshot:
How do I restrict the graph to be only inside the visible area?
The code I use to add graph to panel is this (the border was for me to see panel borders, though it doesnt show for some reason):
Layout<Object, String> layout = new CircleLayout<Object, String> (graphProvider.getGraph());
layout.setSize(panel.getMarketGraphPane().getPreferredSize());
BasicVisualizationServer<Object,String> graphPanel = new BasicVisualizationServer<Object,String>(layout);
graphPanel.setBorder(new EtchedBorder());
graphPanel.setSize(panel.getMarketGraphPane().getPreferredSize());
panel.getMarketGraphPane().add(graphPanel, BorderLayout.CENTER);
panel.getMarketGraphPane().revalidate();

too little informations for the actual image
1 depends
what Size returns (generated graph, by using JUNG), are you set there setSize(int, int) too,
if is graph resiziable,
2) remove
layout.setSize(panel.getMarketGraphPane().getPreferredSize());
and
graphPanel.setSize(panel.getMarketGraphPane().getPreferredSize());
you can't to setSize for Object placed to the BorderLayout.CENTER, and I think that is possible directly put (generated graph, using JUNG. It produces JPanel object) to the BorderLayout.CENTER area, try that maybe your twice setSize generated some mess
and then you can call only
panel.add(graphPanel, BorderLayout.CENTER);
panel.revalidate();
panel.repaint();
3) another two choises (without clean-up setSize)
call pack(); to the Top-Level Container, notice carefully with LCD/LED monitors bounds
put that to the JScrollPane

use GraphZoomScrollPane to add zoom-able graph scrollpane container for VisualizationViewer object as follows:
GraphZoomScrollPane pane = new GraphZoomScrollPane(visualizationViewer);
JPanel panel = new JPanel();
BorderLayout panelMapLayout = new BorderLayout();
panel.setLayout(panelMapLayout);
panel.add(pane, BorderLayout.CENTER);