2003-2004 Silicon Graphics, Inc.
glPointParameter 3G
glPointParameter glPointParameterf glPointParameterx glPointParameterfv glPointParameterxv specify parameters for point rasterization

## C Specification

void `glPointParameterf` GLenum pname GLfloat param void `glPointParameterx` GLenum pname GLfixed param

## Parameters

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.

## C Specification

void `glPointParameterfv` GLenum pname const GLfloat * params void `glPointParameterxv` GLenum pname const GLfixed * params

## Parameters

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.

## Description

`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`.

## Notes

If the point size lower bound is greater than the upper bound, then the point size after clamping is undefined.

## Errors

`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`.

## Associated Gets

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`

## See Also

glEnable, glGet, glLight, glLightModel

## Copyright

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/.