On a past cruise, the stateroom TV provides all sorts of plug ins on the back for various connections. Ship provided TV is supplied from RG-6 with Type F Connectors, as it should, for the long wiring requirements.
In an effort to watch content from a laptop computer (with hdmi output) and with the proper external monitor cable is possible hardware-wise. However the Cruise line's TV remote is spartan and lacks the capability to switch the TV over to HDMI input.
For the next cruise, I plan to carry a smart remote, such as the Logitech Harmony, in order to hopefully allow the connectivity to work.
Your experiences with computer to stateroom TV will be most welcome.
Thanks and Happy Cruising.