3 possibilities:
1st: he didn't read it
go read it!
2nd: he did read the thread, but just doesn't know much about it
3rd: he doesn't understand. Me, having had problems understanding the word UP would accept this...
Okay, i give it a try though i'm walking on VERY thin ice here:
MTex (or Megatexel) is a million texels (textures-pixels) your video card has to draw for one screen. The more the worse. As a display setting of 1024x768 makes 786432 pixels, a higher value than 0.78 prooves, that your card has to draw more texels than what will be visible in the final screen. The reasons for this are many, where some are connected to the quality of the displayed screen (e.g. high resolution or multi-layered textures) and others to the discussed vis-problems, where your video-card 'thinks', it must draw texels, but which will later be covered by texels of nearer brushes. For these, it's an important aim of mapping to keep these unneccessary drawn texels as few as possible, e.g. by making HINT brushes or using textures in a higher scale.
As far as I understand, a brush-side completely covered with a texture of a 4x4 texture makes 16 texels, but also if it was so far away, that it is just visible in 1 pixel. Giving this brush-side the same texture, but scaled to half its size, this would make 64 texels (8x8).
64 texels for one pixel is maybe more than neccessary, so you can:
scale the texture up (i've learned this word
) to reduce the texels or
tell the videocard that it don't have to draw them.
Now the easy part:
FPS are frames per second, the amount of screens your videocard draws in one second: the higher the better
If something is wrong, post correction a.s.a.p.!