glGetMaterialiv

GLGETMATERIAL(3G)					    GLGETMATERIAL(3G)



NAME
       glGetMaterialfv, glGetMaterialiv - return material parameters


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


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
			     integer value.  If the internal value is outside
			     the range [-1,  1],  the  corresponding  integer
			     return  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
			     integer value.  If the internal value is outside
			     the range [-1,  1],  the  corresponding  integer
			     return  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
			     integer value.  If the internal value is outside
			     the range [-1,  1],  the  corresponding  integer
			     return  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 repre-
			     sentable  integer	value.	If the internal value
			     is outside the range [-1, 1.0], the  correspond-
			     ing  integer return value is undefined. The ini-
			     tial 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
			     lighting.)	 Integer values, when requested,  are
			     computed 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(3G)



							    GLGETMATERIAL(3G)