private void initFramebuffer(){
        int fb = 0;
        gl.glGenFramebuffers(1, ID_BUFFER);
        fb = ID_BUFFER.get(0);
        gl.glBindFramebuffer(GL_FRAMEBUFFER, fb);

        // The texture we're going to render to
        int renderedTexture;
        gl.glGenTextures(1, ID_BUFFER);
        renderedTexture = ID_BUFFER.get(0);

        // "Bind" the newly created texture : all future texture functions will modify this texture
        gl.glBindTexture(GL_TEXTURE_2D, renderedTexture);

        // Give an empty image to OpenGL ( the last "0" )
        gl.glTexImage2D(GL_TEXTURE_2D, 0,GL_RGBA, 512, 512, 0, GL_RGBA, GL_UNSIGNED_BYTE, null);

        // Poor filtering. Needed !
        gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

        // The depth buffer
//      int depthrenderbuffer;
//      gl.glGenRenderbuffers(1, ID_BUFFER);
//      depthrenderbuffer = ID_BUFFER.get(0);
//      gl.glBindRenderbuffer(GL_RENDERBUFFER, depthrenderbuffer);
//      gl.glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT32, 512, 512);
//      gl.glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthrenderbuffer);

        // Set "renderedTexture" as our colour attachement #0
        gl.glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, renderedTexture, 0);

        // Set the list of draw buffers.
        IntBuffer db = IntBuffer.allocate(1);
        db.put(GL_COLOR_ATTACHMENT0);
        gl.glDrawBuffers(1, db); // "1" is the size of DrawBuffers

        if(gl.glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
            return;

        gl.glBindTexture(GL_TEXTURE_2D, 0);
        gl.glBindFramebuffer(GL_FRAMEBUFFER, 0);

        this.frameBuffer = fb;
        this.renderedTexture = renderedTexture;
    }

    public void display(GLAutoDrawable drawable) {
        this.gl = drawable.getGL().getGL4();
        this.gl.glBindTexture(GL_TEXTURE_2D, 0);
        this.gl.glBindFramebuffer(GL_FRAMEBUFFER, this.frameBuffer);
        this.gl.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        callback.render(this); // Render Stuff, with the FrameBuffer bound (for tests I render to the left half of the screen)

        this.gl.glBindFramebuffer(GL_FRAMEBUFFER, 0);

        this.gl.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        callback.render(this); //Render Stuff again, this time onscreen on the left half
        [...] // Render rendererdTexture to the right half of the screen
    }