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GLGETMATERIAL()						       GLGETMATERIAL()

NAME
       glGetMaterialfv,	glGetMaterialiv	- return material parameters

C SPECIFICATION
       void glGetMaterialfv( GLenum face,
			     GLenum pname,
			     GLfloat *params )
       void glGetMaterialiv( GLenum face,
			     GLenum pname,
			     GLint *params )

       delim $$

PARAMETERS
       face    Specifies   which  of  the  two	materials  is  being  queried.
	       GL_FRONT	or GL_BACK are accepted, representing  the  front  and
	       back materials, respectively.

       pname   Specifies   the	material  parameter  to	 return.   GL_AMBIENT,
	       GL_DIFFUSE,   GL_SPECULAR,   GL_EMISSION,   GL_SHININESS,   and
	       GL_COLOR_INDEXES	are accepted.

       params  Returns the requested data.

DESCRIPTION
       glGetMaterial  returns in params	the value or values of parameter pname
       of material face. Six parameters	are defined:

       GL_AMBIENT	     params returns  four  integer  or	floating-point
			     values  representing  the	ambient	reflectance of
			     the material.  Integer  values,  when  requested,
			     are  linearly  mapped from	the internal floating-
			     point representation such that 1.0	 maps  to  the
			     most  positive  representable  integer value, and
			     -1.0 maps to the most negative representable  in-
			     teger  value.   If	 the internal value is outside
			     the range [-1, 1],	the corresponding integer  re-
			     turn  value  is  undefined.  The initial value is
			     (0.2, 0.2,	0.2, 1.0)

       GL_DIFFUSE	     params returns  four  integer  or	floating-point
			     values  representing  the	diffuse	reflectance of
			     the material.  Integer  values,  when  requested,
			     are  linearly  mapped from	the internal floating-
			     point representation such that 1.0	 maps  to  the
			     most  positive  representable  integer value, and
			     -1.0 maps to the most negative representable  in-
			     teger  value.   If	 the internal value is outside
			     the range [-1, 1],	the corresponding integer  re-
			     turn  value  is  undefined.  The initial value is
			     (0.8, 0.8,	0.8, 1.0).

       GL_SPECULAR	     params returns  four  integer  or	floating-point
			     values  representing  the specular	reflectance of
			     the material.  Integer  values,  when  requested,
			     are  linearly  mapped from	the internal floating-
			     point representation such that 1.0	 maps  to  the
			     most  positive  representable  integer value, and
			     -1.0 maps to the most negative representable  in-
			     teger  value.   If	 the internal value is outside
			     the range [-1, 1],	the corresponding integer  re-
			     turn value	is undefined. The initial value	is (0,
			     0,	0, 1).

       GL_EMISSION	     params  returns  four  integer  or	floating-point
			     values representing the emitted  light  intensity
			     of	the material.  Integer values, when requested,
			     are  linearly  mapped from	the internal floating-
			     point representation such that 1.0	 maps  to  the
			     most  positive  representable  integer value, and
			     -1.0 maps to the most negative representable  in-
			     teger  value.   If	 the internal value is outside
			     the range [-1, 1.0],  the	corresponding  integer
			     return  value  is undefined. The initial value is
			     (0, 0, 0, 1).

       GL_SHININESS	     params  returns  one  integer  or	floating-point
			     value  representing  the specular exponent	of the
			     material.	Integer	values,	 when  requested,  are
			     computed  by rounding the internal	floating-point
			     value to the nearest integer value.  The  initial
			     value is 0.

       GL_COLOR_INDEXES	     params  returns  three  integer or	floating-point
			     values representing  the  ambient,	 diffuse,  and
			     specular  indices of the material.	 These indices
			     are used only for color index lighting.  (All the
			     other parameters are used only  for  RGBA	light-
			     ing.)   Integer  values, when requested, are com-
			     puted by  rounding	 the  internal	floating-point
			     values to the nearest integer values.

NOTES
       If an error is generated, no change is made to the contents of params.

ERRORS
       GL_INVALID_ENUM is generated if face or pname is	not an accepted	value.

       GL_INVALID_OPERATION  is	generated if glGetMaterial is executed between
       the execution of	glBegin	and the	corresponding execution	of glEnd.

SEE ALSO
       glMaterial

							       GLGETMATERIAL()

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