glPointParameter — specify point parameters
void glPointParameterf (GLenum pname, GLfloat param); void glPointParameteri (GLenum pname, GLint param);
Specifies a single-valued point parameter. GL_POINT_SIZE_MIN
, GL_POINT_SIZE_MAX
,
GL_POINT_FADE_THRESHOLD_SIZE
, and GL_POINT_SPRITE_COORD_ORIGIN
are accepted.
Specifies the value that pname will be set to.
void glPointParameterfv (GLenum pname, const GLfloat *params); void glPointParameteriv (GLenum pname, const GLint *params);
Specifies a point parameter. GL_POINT_SIZE_MIN
, GL_POINT_SIZE_MAX
, GL_POINT_DISTANCE_ATTENUATION
,
GL_POINT_FADE_THRESHOLD_SIZE
, and GL_POINT_SPRITE_COORD_ORIGIN
are accepted.
Specifies the value or values to be assigned to pname. GL_POINT_DISTANCE_ATTENUATION
requires an array of three
values. All other parameters accept an array containing only a single value.
The following values are accepted for pname:
params is a single floating-point value that specifies the minimum point size. The default value is 0.0.
params is a single floating-point value that specifies the maximum point size. The default value is 1.0.
params is a single floating-point value that specifies the threshold value to which point sizes are clamped if they exceed the specified value. The default value is 1.0.
params is an array of three floating-point values that specify the coefficients used for scaling the computed point size. The default values are (1, 0, 0).
params is a single enum specifying the point sprite texture coordinate origin, either GL_LOWER_LEFT
or
GL_UPPER_LEFT
. The default value is GL_UPPER_LEFT
.
glPointParameter is available only if the GL version is 1.4 or greater.
GL_POINT_SPRITE_COORD_ORIGIN
is available only if the GL version is 2.0 or greater.
GL_INVALID_VALUE
is generated If the value specified for GL_POINT_SIZE_MIN
, GL_POINT_SIZE_MAX
, or
GL_POINT_FADE_THRESHOLD_SIZE
is less than zero.
GL_INVALID_ENUM
is generated If the value specified for GL_POINT_SPRITE_COORD_ORIGIN
is not
GL_LOWER_LEFT
or GL_UPPER_LEFT
.
If the value for GL_POINT_SIZE_MIN
is greater than GL_POINT_SIZE_MAX
, the point size after clamping is undefined,
but no error is generated.
glGet with argument GL_POINT_SIZE_MIN
glGet with argument GL_POINT_SIZE_MAX
glGet with argument GL_POINT_FADE_THRESHOLD_SIZE
glGet with argument GL_POINT_DISTANCE_ATTENUATION
glGet with argument GL_POINT_SPRITE_COORD_ORIGIN