They worked really well.
Then I saw a blog post that mentioned Minetest is available for the Raspberry Pi and needs OpenGL.
Minetest is an open source game similar to Minecraft, but not Minecraft. You get the full survival, crafting, making, night, day, mobs and mods, massive worlds and full network play experience.
But again, it's not Minecraft. You cannot use network play between Minetest and Minecraft.
So after a quick apt-get install minetest I had version 4.10 installed on the Pi3.
No messing with .deb files compiling from source. The latest version is 4.13 if you want to roll your own.
Then went into raspi-config and enabled OpenGL.
I also changed the memory split to give 256MB to the GPU. Not sure if it needs that much but thought it would be a good idea.
Rebooted and selected Minetest from the Games menu. It works!
Here is a video of it running on the Raspberry Pi 3.
In the video the effects are all on. It's running full screen 1280x1024 and is really smooth.
If you watch the video you'll see that every so often the screen goes to a lovely rainbow pattern. This I believe is an indicator of a power/heat issue. Let's just say Minetest with the current OpenGL drivers give the GPU a complete work out and at about 80deg C rather than tipping over it protects itself. A quick blow on the GPU and it all works again.
Minetest runs really well on the Raspberry Pi already. More optimisation is expected in the OpenGL drivers which should make it even better and hopefully help with the heat/power problem.
For me I've just spent £1.50 on a fan to put on top of the heat sink I bought and the PiParty. The Pimoroni Ninja Coupe Case I have my Pi3 in has an opening for a heat sink so I splashed out the £1.00 to get one. Form the £2.50 is |a small price to pay for the full on Minetest experience on the Raspberry Pi 3 and I expect it will enable other OpenGL heavy programs to run better and for longer as well.
Additional Points
I had local network play working between the Raspberry Pi and a Windows 10 laptop. Strangely with all effects enabled the Raspberry Pi graphics were better.
Had Windows 10 start the server with Pi as a Client and vice versa so both options worked.
I connected to some public Minetest servers and again worked perfectly.
The article that kicked all this off for me has lots of additional useful information. So much so here it is again, http://www.ocsmag.com/2016/04/04/mining-for-education/
Time to have fun again!