float x0,y0;
	private void cerc(GL2 gl, float raza) {
		float x,y;
		gl.glBegin(GL2.GL_LINE_LOOP);
		for (float unghi = 0; unghi < 2* Math.PI; unghi += 0.1f) {
			x= x0 + raza * (float)Math.cos(unghi);
			y= y0 + raza * (float)Math.sin(unghi);
			gl.glColor3d(Math.random(), Math.random(), Math.random());
			gl.glVertex2f(x, y);
		}
		gl.glEnd();
		x0 += 0.005f;
		y0 += 0.001f;
	}