The forum is for discussion, once something gets worthy of future implementation it should go to the issue tracker, see

here. It's because topics in the forum tend to scroll away into oblivion soon, and we easily forget what was where - there's a lot of noise on the forums.

Linear distribution isn't very suitable for depth mapping because it doesn't reflect the changing detail of what you see with distance. If you have a resolution of 10m, it's 10m in front of you, and it's 10m also 1km away. Clearly you'd need the closer objects to have a better resolution, while the distant ones can have less values from the available range. Basically, you want the precision to be tied to the screen size of the objects, since you are doing post-process effects on the screen.

Since the projected screen size of objects is proportional to the reciprocal of geometry depth (1/depth), a function that maps the available range best is the one that has its derivative proportional to 1/depth. That function is the logarithm, and that's what we are using.