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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 parame-ters parameters
       ters 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 nega-tive negative
                             tive 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 nega-tive negative
                             tive 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 nega-tive negative
                             tive 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 nega-tive negative
                             tive representable integer 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.) lighting.)
                             ing.)  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)