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GLGETMAP()							      GLGETMAP()

NAME
     glGetMapdv, glGetMapfv, glGetMapiv - return evaluator parameters

C SPECIFICATION
     void glGetMapdv( GLenum target,
		      GLenum query,
		      GLdouble *v )
     void glGetMapfv( GLenum target,
		      GLenum query,
		      GLfloat *v )
     void glGetMapiv( GLenum target,
		      GLenum query,
		      GLint *v )

     delim $$

PARAMETERS
     target  Specifies	the  symbolic  name  of  a  map.   Accepted  values  are
	     GL_MAP1_COLOR_4, GL_MAP1_INDEX, GL_MAP1_NORMAL, GL_MAP1_TEXTURE_CO-
	     ORD_1,	 GL_MAP1_TEXTURE_COORD_2,	GL_MAP1_TEXTURE_COORD_3,
	     GL_MAP1_TEXTURE_COORD_4,	  GL_MAP1_VERTEX_3,    GL_MAP1_VERTEX_4,
	     GL_MAP2_COLOR_4, GL_MAP2_INDEX, GL_MAP2_NORMAL, GL_MAP2_TEXTURE_CO-
	     ORD_1,	 GL_MAP2_TEXTURE_COORD_2,	GL_MAP2_TEXTURE_COORD_3,
	     GL_MAP2_TEXTURE_COORD_4, GL_MAP2_VERTEX_3, and GL_MAP2_VERTEX_4.

     query   Specifies	which  parameter  to  return.	Symbolic names GL_COEFF,
	     GL_ORDER, and GL_DOMAIN are accepted.

     v	     Returns the requested data.

DESCRIPTION
     glMap1 and glMap2 define evaluators.  glGetMap  returns  evaluator  parame-
     ters.   target  chooses  a  map,  query selects a specific parameter, and v
     points to storage where the values will be returned.

     The acceptable values for the target parameter are described in the  glMap1
     and glMap2 reference pages.

     query can assume the following values:

     GL_COEFF	    v  returns	the  control  points for the evaluator function.
		    One-dimensional evaluators return  $order$	control  points,
		    and  two-dimensional evaluators return $uorder times vorder$
		    control points.  Each control point consists  of  one,  two,
		    three,  or four integer, single-precision floating-point, or
		    double-precision floating-point  values,  depending  on  the
		    type  of the evaluator.  The GL returns two-dimensional con-
		    trol points in row-major order,  incrementing  the	$uorder$
		    index  quickly and the $vorder$ index after each row.  Inte-
		    ger values, when requested, are computed by rounding the in-
		    ternal floating-point values to the nearest integer values.

     GL_ORDER	    v returns the order of the evaluator  function.   One-dimen-
		    sional  evaluators	return a single value, $order$. The ini-
		    tial value is 1.  Two-dimensional evaluators return two val-
		    ues, $uorder$ and $vorder$. The initial value is 1,1.

     GL_DOMAIN	    v returns the linear $u$ and $v$ mapping  parameters.   One-
		    dimensional  evaluators return two values, $u1$ and $u2$, as
		    specified by glMap1.  Two-dimensional evaluators return four
		    values ($u1$, $u2$, $v1$, and $v2$) as specified by  glMap2.
		    Integer values, when requested, are computed by rounding the
		    internal  floating-point  values to the nearest integer val-
		    ues.

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

ERRORS
     GL_INVALID_ENUM is generated if either target or query is not  an	accepted
     value.

     GL_INVALID_OPERATION  is generated if glGetMap is executed between the exe-
     cution of glBegin and the corresponding execution of glEnd.

SEE ALSO
     glEvalCoord, glMap1, glMap2

								      GLGETMAP()

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