NAME
glGetMapdv, glGetMapfv, glGetMapiv
- return evaluator parameters
C SPECIFICATION
void ggllGGeettMMaappddvv(
GLenum _t_a_r_g_e_t,
GLenum _q_u_e_r_y,
GLdouble _*_v )
void ggllGGeettMMaappffvv(
GLenum _t_a_r_g_e_t,
GLenum _q_u_e_r_y,
GLfloat _*_v )
void ggllGGeettMMaappiivv(
GLenum _t_a_r_g_e_t,
GLenum _q_u_e_r_y,
GLint _*_v )
delim $$
PARAMETERS
-
_t_a_r_g_e_t
-
Specifies the symbolic name of a map.
Accepted values are
GGLL__MMAAPP11__CCOOLLOORR__44,
GGLL__MMAAPP11__IINNDDEEXX,
GGLL__MMAAPP11__NNOORRMMAALL,
GGLL__MMAAPP11__TTEEXXTTUURREE__CCOOOORRDD__11,
GGLL__MMAAPP11__TTEEXXTTUURREE__CCOOOORRDD__22,
GGLL__MMAAPP11__TTEEXXTTUURREE__CCOOOORRDD__33,
GGLL__MMAAPP11__TTEEXXTTUURREE__CCOOOORRDD__44,
GGLL__MMAAPP11__VVEERRTTEEXX__33,
GGLL__MMAAPP11__VVEERRTTEEXX__44,
GGLL__MMAAPP22__CCOOLLOORR__44,
GGLL__MMAAPP22__IINNDDEEXX,
GGLL__MMAAPP22__NNOORRMMAALL,
GGLL__MMAAPP22__TTEEXXTTUURREE__CCOOOORRDD__11,
GGLL__MMAAPP22__TTEEXXTTUURREE__CCOOOORRDD__22,
GGLL__MMAAPP22__TTEEXXTTUURREE__CCOOOORRDD__33,
GGLL__MMAAPP22__TTEEXXTTUURREE__CCOOOORRDD__44,
GGLL__MMAAPP22__VVEERRTTEEXX__33, and
GGLL__MMAAPP22__VVEERRTTEEXX__44.
-
_q_u_e_r_y
-
Specifies which parameter to return.
Symbolic names
GGLL__CCOOEEFFFF,
GGLL__OORRDDEERR, and
GGLL__DDOOMMAAIINN are accepted.
-
_v
-
Returns the requested data.
DESCRIPTION
ggllMMaapp11 and ggllMMaapp22 define evaluators.
ggllGGeettMMaapp returns evaluator parameters.
_t_a_r_g_e_t chooses a map,
_q_u_e_r_y selects a specific parameter,
and _v points to storage where the values will be returned.
The acceptable values for the _t_a_r_g_e_t parameter are described
in the ggllMMaapp11 and ggllMMaapp22 reference pages.
_q_u_e_r_y can assume the following values:
-
GGLL__CCOOEEFFFF
-
_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 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.
-
GGLL__OORRDDEERR
-
_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.
-
GGLL__DDOOMMAAIINN
-
_v returns the linear $u$ and $v$ mapping parameters.
One-dimensional evaluators return two values,
$u1$ and $u2$,
as specified by ggllMMaapp11.
Two-dimensional evaluators return four values
($u1$, $u2$, $v1$, and $v2$)
as specified by ggllMMaapp22.
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
GGLL__IINNVVAALLIIDD__EENNUUMM is generated if either _t_a_r_g_e_t or _q_u_e_r_y is not
an accepted value.
GGLL__IINNVVAALLIIDD__OOPPEERRAATTIIOONN is generated if ggllGGeettMMaapp
is executed between the execution of ggllBBeeggiinn
and the corresponding execution of ggllEEnndd.
SEE ALSO
ggllEEvvaallCCoooorrdd((33GG)),
ggllMMaapp11((33GG)),
ggllMMaapp22((33GG))