GLPOINTSIZE(3G) 														   GLPOINTSIZE(3G)

NAME

       glPointSize - specify the diameter of rasterized points

C SPECIFICATION

       void glPointSize( GLfloat size )

PARAMETERS

       size  Specifies the diameter of rasterized points.  The initial value is 1.

DESCRIPTION

       glPointSize  specifies  the  rasterized	diameter  of  both  aliased and antialiased points.  Using a point size other than 1 has different
       effects, depending on whether point antialiasing is enabled.  To enable and disable point antialiasing, call glEnable  and  glDisable  with
       argument GL_POINT_SMOOTH. Point antialiasing is initially disabled.

       If  point  antialiasing	is disabled, the actual size is determined by rounding the supplied size to the nearest integer.  (If the rounding
       results in the value 0, it is as if the point size were 1.)  If the rounded size is odd, then the center point (x, y) of the pixel fragment
       that represents the point is computed as

								 ( |_xw_|+.5, |_yw_|+.5)

       where  w subscripts indicate window coordinates.  All pixels that lie within the square grid of the rounded size centered at (x, y) make up
       the fragment.  If the size is even, the center point is

								 ( |_xw+.5_|, |_yw+.5_|)

       and the rasterized fragment's centers are the half-integer window coordinates within the square of the rounded size  centered  at  (x,  y).
       All  pixel fragments produced in rasterizing a nonantialiased point are assigned the same associated data, that of the vertex corresponding
       to the point.

       If antialiasing is enabled, then point rasterization produces a fragment for each pixel square that intersects the region lying within  the
       circle  having  diameter equal to the current point size and centered at the point's (xw, yw).  The coverage value for each fragment is the
       window coordinate area of the intersection of the circular region with the corresponding pixel square.  This value is saved and used in the
       final rasterization step.  The data associated with each fragment is the data associated with the point being rasterized.

       Not  all  sizes are supported when point antialiasing is enabled.  If an unsupported size is requested, the nearest supported size is used.
       Only size 1 is guaranteed to be supported; others depend on the implementation.	To query the range of supported sizes and the size differ-
       ence  between  supported sizes within the range, call glGet with arguments GL_SMOOTH_POINT_SIZE_RANGE and GL_SMOOTH_POINT_SIZE_GRANULARITY.
       For  aliased  points,  query  the  supported  ranges  and  granularity  with   glGet   with   arguments	 GL_ALIASED_POINT_SIZE_RANGE   and
       GL_ALIASED_POINT_SIZE_GRANULARITY.

NOTES

       The  point  size  specified  by	glPointSize  is  always  returned  when  GL_POINT_SIZE	is queried.  Clamping and rounding for aliased and
       antialiased points have no effect on the specified value.

       A non-antialiased point size may be clamped to an implementation-dependent maximum.  Although this maximum cannot be queried, it must be no
       less than the maximum value for antialiased points, rounded to the nearest integer value.

       GL_POINT_SIZE_RANGE  and GL_POINT_SIZE_GRANULARITY are deprecated in GL versions 1.2 and greater.  Their functionality has been replaced by
       GL_SMOOTH_POINT_SIZE_RANGE and GL_SMOOTH_POINT_SIZE_GRANULARITY.

ERRORS

       GL_INVALID_VALUE is generated if size is less than or equal to 0.

       GL_INVALID_OPERATION is generated if glPointSize is executed between the execution of glBegin and the corresponding execution of glEnd.

ASSOCIATED GETS

       glGet with argument GL_POINT_SIZE
       glGet with argument GL_ALIASED_POINT_SIZE_RANGE
       glGet with argument GL_ALIASED_POINT_SIZE_GRANULARITY
       glGet with argument GL_SMOOTH_POINT_SIZE_RANGE
       glGet with argument GL_SMOOTH_POINT_SIZE_GRANULARITY
       glIsEnabled with argument GL_POINT_SMOOTH

SEE ALSO

       glEnable(3G)

																   GLPOINTSIZE(3G)