Microsoft DirectX 8.1 (C++)

D3DLIGHT8

Defines a set of lighting properties.

typedef struct _D3DLIGHT8 {
    D3DLIGHTTYPE    Type;
    D3DCOLORVALUE   Diffuse;
    D3DCOLORVALUE   Specular;
    D3DCOLORVALUE   Ambient;
    D3DVECTOR       Position;
    D3DVECTOR       Direction;
    float           Range;
    float           Falloff;
    float           Attenuation0;
    float           Attenuation1;
    float           Attenuation2;
    float           Theta;
    float           Phi;
} D3DLIGHT8;

Members

Type: Type of the light source. This value is one of the members of the D3DLIGHTTYPE enumerated type.
Diffuse: Diffuse color emitted by the light. This member is a D3DCOLORVALUE structure.
Specular: Specular color emitted by the light. This member is a D3DCOLORVALUE structure.
Ambient: Ambient color emitted by the light. This member is a D3DCOLORVALUE structure.
Position: Position of the light in world space, specified by a D3DVECTOR structure. This member has no meaning for directional lights and is ignored in that case.
Direction: Direction that the light is pointing in world space, specified by a D3DVECTOR structure. This member only has meaning only for directional and spotlights. This vector need not be normalized, but it should have a nonzero length.
Range: Distance beyond which the light has no effect. The maximum allowable value for this member is the square root of FLT_MAX. This member does not affect directional lights.
Falloff: Decrease in illumination between a spotlight's inner cone (the angle specified by Theta) and the outer edge of the outer cone (the angle specified by Phi). The effect of falloff on the lighting is subtle. Furthermore, a small performance penalty is incurred by shaping the falloff curve. For these reasons, most developers set this value to 1.0.
Attenuation0, Attenuation1, and Attenuation2: Values specifying how the light intensity changes over distance. Attenuation values are ignored for directional lights. These members represent attenuation constants. For information on attenuation, see Light Position, Range, and Attenuation. Valid values for these members range from 0.0 to infinity. For non-directional lights, all three attenuation values should not be set to 0.0 at the same time.
Theta: Angle, in radians, of a spotlight's inner cone—that is, the fully illuminated spotlight cone. This value must be in the range from 0 through the value specified by Phi.
Phi: Angle, in radians, defining the outer edge of the spotlight's outer cone. Points outside this cone are not lit by the spotlight. This value must be between 0 and pi.

Requirements

Header: Declared in D3d8types.h.

D3DLIGHT8

Members

Requirements

See Also