glGetMap(3G)glGetMap(3G)NAME
glGetMap, glGetMapdv, glGetMapfv, glGetMapiv - return evaluator parame‐
ters
SYNOPSIS
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
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_VERTEX_4. Spec‐
ifies which parameter to return. Symbolic names GL_COEFF, GL_ORDER, and
GL_DOMAIN are accepted. Returns the requested data.
DESCRIPTIONglMap1() 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: v returns the control points for
the evaluator function. One-dimensional evaluators return order control
points, and two-dimensional evaluators return uorder times vorder con‐
trol 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 val‐
ues, when requested, are computed by rounding the internal floating-
point values to the nearest integer values. 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. v returns the
linear u and v mapping parameters. One-dimensional evaluators return
two values, u1 and u2, as specified by glMap1(). Two-dimensional evalu‐
ators 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
accepted value.
GL_INVALID_OPERATION is generated if glGetMap() is executed between the
execution of glBegin() and the corresponding execution of glEnd().
SEE ALSOglEvalCoord(3), glMap1(3), glMap2(3)glGetMap(3G)