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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_TEX-
	       TURE_COORD_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_TEX-
	       TURE_COORD_1, GL_MAP2_TEXTURE_COORD_2, GL_MAP2_TEXTURE_COORD_3,
	       GL_MAP2_TEXTURE_COORD_4,	  GL_MAP2_VERTEX_3,  and  GL_MAP2_VER-
	       TEX_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 para-
       meters.	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  con-
		      sists of one, two, three,	or four	integer, single-preci-
		      sion  floating-point, or double-precision	floating-point
		      values, depending	on the type of the evaluator.  The  GL
		      returns  two-dimensional control points in row-major or-
		      der, incrementing	the $uorder$  index  quickly  and  the
		      $vorder$ index after each	row.  Integer values, when re-
		      quested, are computed by rounding	the internal floating-
		      point values to the nearest integer values.

       GL_ORDER	      v	 returns the order of the evaluator function.  One-di-
		      mensional	evaluators return a single value, $order$. The
		      initial value is 1.  Two-dimensional  evaluators	return
		      two  values, $uorder$ 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  evalua-
		      tors  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 values.

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  ac-
       cepted value.

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

SEE ALSO
       glEvalCoord, glMap1, glMap2

								    GLGETMAP()

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