Defines constants that describe the fog mode.
typedef enum D3DFOGMODE { D3DFOG_NONE = 0, D3DFOG_EXP = 1, D3DFOG_EXP2 = 2, D3DFOG_LINEAR = 3, D3DFOG_FORCE_DWORD = 0x7fffffff, } D3DFOGMODE, *LPD3DFOGMODE;
Fog effect intensifies exponentially, according to the following formula.
Fog effect intensifies exponentially with the square of the distance, according to the following formula.
Fog effect intensifies linearly between the start and end points, according to the following formula.
This is the only fog mode currently supported.
The values in this enumerated type are used by the D3DRS_FOGTABLEMODE and D3DRS_FOGVERTEXMODE render states.
Fog can be considered a measure of visibility—the lower the fog value produced by a fog equation, the less visible an object is.