PointCloud from velodyne in rviz

Hello all! I am trying to add a velodyne sensor (VLP-16) to an UAV (the iris model in px4). I know that there are more questions on it but as far as I understood them, I don't have their issues. I can see the sensor in Gazebo, it's frame is connected to the fixed frame (see tf tree image below), it is receiving messages, the status is ok in Rviz but I cannot see anything. I already made the [question to the px4](https://github.com/PX4/sitl_gazebo/issues/159) people but thought someone here might know what am I missing. So in my urdf I have Here is the tf tree (the parent is base_link and unicorn is on the bottom left):  And here is Rviz  The launch is their posix_sitl.launch plus robot and joint publisher: Here is what the gazebo looks like