gb.setPaint(new GradientPaint(0, INSET, topColoring, 0, buttonHeight, bottomColoring, false));
// Paint the first layer
gb.fillRoundRect(INSET, INSET, buttonWidth, buttonHeight, arc, arc);
gb.setColor(Color.darkGray);
gb.drawRoundRect(INSET, INSET, buttonWidth, buttonHeight, arc, arc);
// set up paint data fields for second layer
int highlightHeight = buttonHeight - (HIGHLIGHT_INSET * 2);
int highlightWidth = buttonWidth - (HIGHLIGHT_INSET * 2);
int highlightArc = highlightHeight;