C SPECIFICATION
       void GLAPIENTRY glEvalCoord1d( GLdouble u )
       void GLAPIENTRY glEvalCoord1f( GLfloat u )
       void GLAPIENTRY glEvalCoord2d( GLdouble u,
                                      GLdouble v )
       void GLAPIENTRY glEvalCoord2f( GLfloat u,
                                      GLfloat v )

PARAMETERS
       u  Specifies  a value that is the domain coordinate u to the basis func‐
          tion defined in a previous glMap1 or glMap2 command.

       v  Specifies a value that is the domain coordinate v to the basis  func‐
          tion  defined  in  a  previous  glMap2 command.  This argument is not
          present in a glEvalCoord1 command.

C SPECIFICATION
       void GLAPIENTRY glEvalCoord1dv( const GLdouble *u )
       void GLAPIENTRY glEvalCoord1fv( const GLfloat *u )
       void GLAPIENTRY glEvalCoord2dv( const GLdouble *u )
       void GLAPIENTRY glEvalCoord2fv( const GLfloat *u )

PARAMETERS
       u      Specifies a pointer to an array containing either one or two  do‐
              main coordinates.  The first coordinate is u.  The second coordi‐
              nate is v, which is present only in glEvalCoord2 versions.

DESCRIPTION
       glEvalCoord1 evaluates  enabled  one-dimensional  maps  at  argument  u.
       glEvalCoord2  does  the  same  for two-dimensional maps using two domain
       values, u and v.  To define a map, call glMap1 and glMap2; to enable and
       disable it, call glEnable and glDisable.

       When  one  of  the glEvalCoord commands is issued, all currently enabled
       maps of the indicated dimension are evaluated.  Then, for  each  enabled
       map,  it  is as if the corresponding GL command had been issued with the
       computed value.  That is, if GL_MAP1_INDEX or GL_MAP2_INDEX is  enabled,
       a  glIndex  command is simulated.  If GL_MAP1_COLOR_4 or GL_MAP2_COLOR_4
       is enabled, a  glColor  command  is  simulated.   If  GL_MAP1_NORMAL  or
       GL_MAP2_NORMAL  is  enabled,  a normal vector is produced, and if any of
       GL_MAP1_TEXTURE_COORD_1,                        GL_MAP1_TEXTURE_COORD_2,
       GL_MAP1_TEXTURE_COORD_3,                        GL_MAP1_TEXTURE_COORD_4,
       GL_MAP2_TEXTURE_COORD_1,                        GL_MAP2_TEXTURE_COORD_2,
       GL_MAP2_TEXTURE_COORD_3,  or GL_MAP2_TEXTURE_COORD_4 is enabled, then an
       appropriate glTexCoord command is simulated.

       For color, color index, normal, and  texture  coordinates  the  GL  uses
       evaluated  values  instead  of current values for those evaluations that
       are enabled, and current values otherwise, However, the evaluated values
       do not update the current values.  Thus, if glVertex commands are inter‐
       spersed with glEvalCoord commands, the color, normal, and texture  coor‐
       dinates  associated  with  the glVertex commands are not affected by the
       with argument GL_AUTO_NORMAL, glEvalCoord2 generates surface normals an‐
       alytically, regardless of the contents or enabling of the GL_MAP2_NORMAL
       map.  Let

                                       m=__×__

       Then the generated normal n is
                                       n=_____

       If automatic normal generation is disabled, the corresponding normal map
       GL_MAP2_NORMAL, if enabled, is used to produce a normal.  If neither au‐
       tomatic normal generation nor a normal map is enabled, no normal is gen‐
       erated for glEvalCoord2 commands.

ASSOCIATED GETS
       glIsEnabled with argument GL_MAP1_VERTEX_3
       glIsEnabled with argument GL_MAP1_VERTEX_4
       glIsEnabled with argument GL_MAP1_INDEX
       glIsEnabled with argument GL_MAP1_COLOR_4
       glIsEnabled with argument GL_MAP1_NORMAL
       glIsEnabled with argument GL_MAP1_TEXTURE_COORD_1
       glIsEnabled with argument GL_MAP1_TEXTURE_COORD_2
       glIsEnabled with argument GL_MAP1_TEXTURE_COORD_3
       glIsEnabled with argument GL_MAP1_TEXTURE_COORD_4
       glIsEnabled with argument GL_MAP2_VERTEX_3
       glIsEnabled with argument GL_MAP2_VERTEX_4
       glIsEnabled with argument GL_MAP2_INDEX
       glIsEnabled with argument GL_MAP2_COLOR_4
       glIsEnabled with argument GL_MAP2_NORMAL
       glIsEnabled with argument GL_MAP2_TEXTURE_COORD_1
       glIsEnabled with argument GL_MAP2_TEXTURE_COORD_2
       glIsEnabled with argument GL_MAP2_TEXTURE_COORD_3
       glIsEnabled with argument GL_MAP2_TEXTURE_COORD_4
       glIsEnabled with argument GL_AUTO_NORMAL
       glGetMap

SEE ALSO
       glBegin,  glColor,  glEnable,  glEvalMesh, glEvalPoint, glIndex, glMap1,
       glMap2, glMapGrid, glNormal, glTexCoord, glVertex

                                                                GLEVALCOORD(3G)