All of you are noobs, if you go to apple.con/macbookpro you can actually look at the specs of each model which you should have done before posting here. The lower end models only have Intel HD, but the higher end models have Intel HD and Nvidia card which are pretty good. The reason they hve two is so you can swith between them, intel for when you aren't somewhere near a charger and the Nvidia when you want to game or having the laptop plugged in.
You can go ahead and suggest to OP "hey, macs are really expensive you should think of getting a Windows PC if your main focus is to run games". Not something like "macs are loving stuff and aren't designed for games, they are designed for media stuff" ( which isn't even true as macs are used a lot in 3D modeling programs such as 3DSMAX and Maya which use OpenGL, same as Blockland and many other games)
The reason why shaders don't work correctly on Mac is because there is somethig missing in the GPU drivers for Mac that shaders require. Badspot can't fix this because its something out of his hands. Maybe contacting Nvidia and/or AMD for a fix (which should be relatively easy) would make shaders work.
To check what's missing, be on a Mac computer load a map with shaders on and press the ~ button and it should show a bunch of stuff for shaders following "On" and "Off", whatever is off is most likely what you need.
I hope I cleared up some stuff.