Posted by Demoscene Passivist on Jul 19, 2010; 11:44am
URL: https://forum.jogamp.org/Flipped-texture-tp965264p978276.html

It seems everything is already there, u just have to find it :)

com.jogamp.opengl.util.awt.ImageUtil

public static void flipImageVertically(BufferedImage image)

Flips the supplied BufferedImage vertically. This is often a necessary conversion step to display a Java2D image correctly with OpenGL and vice versa.