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<STRONG>NAME</STRONG>
<STRONG>glLineWidth</STRONG> - specify the width of rasterized lines
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glLineWidth</STRONG>( GLfloat <EM>width</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>width</EM> Specifies the width of rasterized lines. The initial
value is 1.
<STRONG>DESCRIPTION</STRONG>
<STRONG>glLineWidth</STRONG> specifies the rasterized width of both aliased
and antialiased lines. Using a line width other than 1 has
different effects, depending on whether line antialiasing is
enabled. To enable and disable line antialiasing, call
<STRONG>glEnable</STRONG> and <STRONG>glDisable</STRONG> with argument <STRONG>GL_LINE_SMOOTH</STRONG>. Line
antialiasing is initially disabled.
If line antialiasing is disabled, the actual width is
determined by rounding the supplied width to the nearest
integer. (If the rounding results in the value 0, it is as
if the line width were 1.) If
| DELTA x | >= | DELTA y |,
<EM>i</EM> pixels are filled in each column that is rasterized, where
<EM>i</EM> is the rounded value of <EM>width</EM>. Otherwise, <EM>i</EM> pixels are
filled in each row that is rasterized.
If antialiasing is enabled, line rasterization produces a
fragment for each pixel square that intersects the region
lying within the rectangle having width equal to the current
line width, length equal to the actual length of the line,
and centered on the mathematical line segment. The coverage
value for each fragment is the window coordinate area of the
intersection of the rectangular region with the
corresponding pixel square. This value is saved and used in
the final rasterization step.
Not all widths can be supported when line antialiasing is
enabled. If an unsupported width is requested, the nearest
supported width is used. Only width 1 is guaranteed to be
supported; others depend on the implementation. To query
the range of supported widths and the size difference
between supported widths within the range, call <STRONG>glGet</STRONG> with
arguments <STRONG>GL_LINE_WIDTH_RANGE</STRONG> and <STRONG>GL_LINE_WIDTH_GRANULARITY</STRONG>.
<STRONG>NOTES</STRONG>
The line width specified by <STRONG>glLineWidth</STRONG> is always returned
when <STRONG>GL_LINE_WIDTH</STRONG> is queried. Clamping and rounding for
aliased and antialiased lines have no effect on the
specified value.
Nonantialiased line width 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 lines, rounded to the nearest integer value.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>width</EM> is less than or equal
to 0.
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glLineWidth</STRONG> is executed
between the execution of <STRONG>glBegin</STRONG> and the corresponding
execution of <STRONG>glEnd</STRONG>.
<STRONG>ASSOCIATED</STRONG> <STRONG>GETS</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_LINE_WIDTH</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_LINE_WIDTH_RANGE</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_LINE_WIDTH_GRANULARITY</STRONG>
<STRONG>glIsEnabled</STRONG> with argument <STRONG>GL_LINE_SMOOTH</STRONG>
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>glEnable</STRONG>
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