public void renderObstacleMap() {
    m_obstaclesFrameBuffer.begin();
    Gdx.gl20.glClearColor(0, 0, 0, 1);
    Gdx.gl20.glClear(Gdx.gl20.GL_COLOR_BUFFER_BIT);

    ByteBuffer buffer = ByteBuffer.allocateDirect(8 * 4);
    buffer.order(ByteOrder.nativeOrder());
    FloatBuffer vertices = buffer.asFloatBuffer();

    m_obstaclesProgram.begin();
    m_obstaclesProgram.setUniformMatrix("u_transform", transform);
    Gdx.gl20.glBindBuffer(GL20.GL_ARRAY_BUFFER, m_vbo);
    Gdx.gl20.glEnableVertexAttribArray(m_genericPositionAttribute);
    Gdx.gl20.glVertexAttribPointer(m_genericPositionAttribute, 2, GL20.GL_FLOAT, false, 8, 0);

    Iterator<GameObject> iterator = controller.getObjectIterator();
    while (iterator.hasNext()) {
        GameObject o = iterator.next();
        if (!o.transparentForLight) {
            // набиваем вершины в буфер
            vertices.position(0);
            vertices.put(o.x); vertices.put(o.y);
            vertices.put(o.x); vertices.put(o.y + o.height);
            vertices.put(o.x + o.width); vertices.put(o.y + o.height);
            vertices.put(o.x + o.width); vertices.put(o.y);

            Gdx.gl20.glBufferData(GL20.GL_ARRAY_BUFFER, buffer.capacity(), buffer, GL20.GL_DYNAMIC_DRAW);
            Gdx.gl20.glDrawArrays(GL20.GL_TRIANGLE_FAN, 0, 4);
        }
    }

    Gdx.gl20.glDisableVertexAttribArray(m_genericPositionAttribute);
    Gdx.gl20.glBindBuffer(GL20.GL_ARRAY_BUFFER, 0);
    m_obstaclesProgram.end();
    m_obstaclesFrameBuffer.end();
}