@Override
	public void paintIcon(Component c, Graphics g, int x, int y) {

		Graphics2D g2d = (Graphics2D) g;
		g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

		try {
			g2d.translate(x, y);
			g2d.setColor(color);
			g2d.fill(shape);
		}
		finally {
			g2d.translate(-x, -y);
		}
	}
A basic arrow that points to the right, with padding on the sides and above.
Ghidra/Framework/Help/src/main/java/help/HelpRightArrowIcon.java