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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 )

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_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_TEXTURE_COORD_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
       parameters.  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 x 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 control points in row-major order,
                      incrementing the uorder index quickly and the vorder
                      index after each row.  Integer values, when requested,
                      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-
                      dimensional 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, u 1 and u 2,
                      as specified by glMap1.  Two-dimensional evaluators
                      return four values (u 1, u 2, v 1, and v 2) 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
       accepted 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()