Currently, the axes for the main and C sticks range from 0-255, with
128 being the mid-point; but this isn't symmetrical: the negative axis
has 128 values not including 0, while the positive axis has 127 values
not including 0.
Normalizing so that the range is 1-255 makes the positive and negative
axes symmetrical. The inability to yield 0 shouldn't be an issue as a
real GC controller cannot yield it anyway.
Tony Gong
c95c43bfb6