void glMapGrid1d
|
( |
GLint un
, GLdouble u1
, GLdouble u2
); |
void glMapGrid1f
|
( |
GLint un
, GLfloat u1
, GLfloat u2
); |
void glMapGrid2d
|
( |
GLint un
, GLdouble u1
, GLdouble u2
, GLint vn
, GLdouble v1
, GLdouble v2
); |
void glMapGrid2f
|
( |
GLint un
, GLfloat u1
, GLfloat u2
, GLint vn
, GLfloat v1
, GLfloat v2
); |
glMapGrid1d
|
( |
un
,
u1
,
u2
) →
None
|
glMapGrid1f
|
( |
un
,
u1
,
u2
) →
None
|
glMapGrid2d
|
( |
un
,
u1
,
u2
,
vn
,
v1
,
v2
) →
None
|
glMapGrid2f
|
( |
un
,
u1
,
u2
,
vn
,
v1
,
v2
) →
None
|
(glMapGrid2 only).
(glMapGrid2 only).
glMapGrid and glEvalMesh are used together to efficiently generate and evaluate a series of evenly-spaced map domain values. glEvalMesh steps through the integer domain of a one- or two-dimensional grid, whose range is the domain of the evaluation maps specified by glMap1 and glMap2.
glMapGrid1 and glMapGrid2 specify the linear grid mappings between the i (or i and j) integer grid coordinates, to the u (or u and v) floating-point evaluation map coordinates. See glMap1 and glMap2 for details of how u and v coordinates are evaluated.
glMapGrid1 specifies a single linear mapping such that integer grid coordinate 0 maps exactly to u1, and integer grid coordinate un maps exactly to u2. All other integer grid coordinates i are mapped so that
glMapGrid2 specifies two such linear mappings. One maps integer grid coordinate i=0 exactly to u1, and integer grid coordinate i=un exactly to u2. The other maps integer grid coordinate j=0 exactly to v1, and integer grid coordinate j=vn exactly to v2. Other integer grid coordinates i and j are mapped such that
The mappings specified by glMapGrid are used identically by glEvalMesh and glEvalPoint.
GL_INVALID_VALUE is generated if either un or vn is not positive.
GL_INVALID_OPERATION is generated if glMapGrid is executed between the execution of glBegin and the corresponding execution of glEnd.
glGet with argument GL_MAP1_GRID_DOMAIN
glGet with argument GL_MAP2_GRID_DOMAIN
glGet with argument GL_MAP1_GRID_SEGMENTS
glGet with argument GL_MAP2_GRID_SEGMENTS