Fog Computation
Fog will affect pixel’s color. Fog equation in OpenGL is (for RGBA mode)
- C = f * Ci + (1 - f) Cf
- f is fog factor : [0,1], represented on i740 by 8 bits using 0.8 fixed point
- Ci is incoming pixel color, Cf is fog color
- if f = 1.0, then Fog is ‘clear’ and Pixel value is unchanged.
PROBLEM!! How do we represent 1.0 in 0.8 fixed format? ( 255 does not equal 1.0!!)