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glPointParameter — specify point parameters
void glPointParameterf( | GLenum | pname, |
| GLfloat | param); |
void glPointParameteri( | GLenum | pname, |
| GLint | param); |
pname
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.
param
Specifies the value that pname will be set to.
void glPointParameterfv( | GLenum | pname, |
| const GLfloat * | params); |
void glPointParameteriv( | GLenum | pname, |
| const GLint * | params); |
pname
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.
params
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:
GL_POINT_SIZE_MIN
params is a single floating-point value that specifies the minimum point size. The default value is 0.0.
GL_POINT_SIZE_MAX
params is a single floating-point value that specifies the maximum point size. The default value is 1.0.
GL_POINT_FADE_THRESHOLD_SIZE
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.
GL_POINT_DISTANCE_ATTENUATION
params is an array of three floating-point values that specify the
coefficients used for scaling the computed point size. The default values
are
GL_POINT_SPRITE_COORD_ORIGIN
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
Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.