glGetMapdv,
glGetMapfv, glGetMapiv
[New
- Windows 95, OEM Service Release 2]
These
functions return evaluator parameters.
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
The symbolic
name of a map. The following are accepted values: 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. The following symbolic names are accepted:
GL_COEFF
The v
parameter returns the control points for the evaluator function.
One-dimensional evaluators return order control points, and two-dimensional
evaluators return uorderxvorder 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. Two-dimensional control points are returned 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
The v
parameter returns the order of the evaluator function. One-dimensional
evaluators return a single value, order. Two-dimensional evaluators
return two values, uorder and vorder.
GL_DOMAIN
The v
parameter returns the linear u and v mapping parameters.
One-dimensional evaluators return two values, u1 and u2, as
specified by glMap1
v
Returns the
requested data.
Remarks
The glGetMap
function returns evaluator parameters. (The glMap1 and glMap2
functions define evaluators.) The target parameter specifies 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 glMap1
If an error
is generated, no change is made to the contents of v.
Error Codes
The following
are the error codes generated and their conditions.
Error
Code |
Condition |
GL_INVALID_ENUM
|
target or query was not an accepted value. |
GL_INVALID_OPERATION
|
glGetMap was called between a call to glBegin and the
corresponding call to glEnd. |
See Also