glPointParameter — specify parameters for point rasterization
void glPointParameterf( | GLenum pname, |
GLfloat param); |
void glPointParameterx( | GLenum pname, |
GLfixed param); |
pname
Specifies the single-valued parameter to be updated.
Can be either
GL_POINT_SIZE_MIN,
GL_POINT_SIZE_MAX, or
GL_POINT_FADE_THRESHOLD_SIZE.
param
Specifies the value that the parameter will be set to.
void glPointParameterfv( | GLenum pname, |
const GLfloat * params); |
void glPointParameterxv( | GLenum pname, |
const GLfixed * params); |
pname
Specifies the parameter to be updated.
Can be either
GL_POINT_SIZE_MIN,
GL_POINT_SIZE_MAX,
GL_POINT_FADE_THRESHOLD_SIZE, or
GL_POINT_DISTANCE_ATTENUATION.
params
Specifies a pointer to the value or values that
pname
will be set to.
glPointParameter
assigns values to point parameters.
glPointParameter
takes two arguments.
pname,
specifies which of several parameters will be modified.
params,
specifies what value or values will be assigned to the
specified parameter.
The parameters that can be specified using
glPointParameter,
and their interpretations are as follows:
GL_POINT_SIZE_MIN
param specifies,
or params
points to the lower bound to which
the derived point size is clamped.
GL_POINT_SIZE_MAX
param specifies,
or params
points to the upper bound to which
the derived point size is clamped.
GL_POINT_FADE_THRESHOLD_SIZE
param specifies,
or params
points to the point fade threshold.
GL_POINT_DISTANCE_ATTENUATION
params
points to the distance attenuation function coefficients
a,
b, and
c.
If the point size lower bound is greater than the upper bound, then the point size after clamping is undefined.
GL_INVALID_ENUM is generated if
pname
is not an accepted value.
GL_INVALID_VALUE is generated
if assigned values for
GL_POINT_SIZE_MIN,
GL_POINT_SIZE_MAX, or
GL_POINT_FADE_THRESHOLD_SIZE
are less then zero.
glGet
with argument GL_POINT_DISTANCE_ATTENUATION
glGet
with argument GL_POINT_FADE_THRESHOLD_SIZE
glGet
with argument GL_POINT_SIZE_MAX
glGet
with argument GL_POINT_SIZE_MIN
Copyright © 2003-2004 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.