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Using paintComponent(Graphics g) on JFrame's glass pane

I am trying to draw on the glass pane part of a JFrame with a marker using g.fillPolygon(xValues, yValues, numPoints) after making the background of the JFrame transparent.

I am using a method to find the location of the cursor and can get the right locations. To force the call of paintComponent(Graphics g) , I am using myGlassPane.repaint() but this deletes the previous part of the segment that I drew.

I am wondering if there is a way to retain what was previously drawn through the paintComponent(Graphics g) method.

I am wondering if there is a way to retain what was previously drawn through the paintComponent(Graphics g) method.

Yes, add whatever you drew before either to a BufferedImage or a List which can allow you to create it...

For example

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