EZ
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12.12 Fog

Fog uses the current blending factor to blends the current fog color with the current color and use the result to color the current vertex. Fog is enabled and disabled with EZ_Enable(EZ_FOG) and EZ_Disable(EZ_FOG). It is disabled by default.

Blending factor is computed by one of the following equations, depending on the current fogMode.

fogMode blending factor
EZ_LINEAR
EZ_EXP
EZ_EXP2

where is the the z-coor of the vertex in the normalized screen space, fogStart fogEnd , fogDensity are state attributes.

If fog is enabled, the color of a vertex is computed using the formula

void EZ_Fogfv(int attrName, float *values);

This function sets the fog state attributes. Attribute is one of

EZ_FOG_MODE, EZ_FOG_START, EZ_FOG_END, EZ_FOG_DENSITY, EZ_FOG_COLOR,EZ_FOG_INDEX+

If attrName is EZ_FOG_MODE, the attribute value must be one of EZ_LINEAR, EZ_EXP and EZ_EXP2. is EZ_FOG_START or EZ_FOG_END, the attribute value must be a floating point number in . If attrName is EZ_FOG_INTENSITY, the value must be a positive floating point number. If attrName is EZ_FOG_COLOR, the values must be RGB tripple, i.e., three floating point numbers in that specify the RGB intensity of the fog color.


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