glLineWidth(3G)		       OpenGL Reference		       glLineWidth(3G)



NAME
     glLineWidth - specify the width of	rasterized lines


C SPECIFICATION
     void glLineWidth( GLfloat width )


PARAMETERS
     width  Specifies the width	of rasterized lines.  The default is 1.0.


DESCRIPTION
     glLineWidth specifies the rasterized width	of both	aliased	and
     antialiased lines.	 Using a line width other than 1.0 has different
     effects, depending	on whether line	antialiasing is	enabled.  Line
     antialiasing is controlled	by calling glEnable and	glDisable with
     argument GL_LINE_SMOOTH.

     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
     |Wx| > |Wy|, i pixels are filled in each column that is rasterized, where
     i is the rounded value of width.  Otherwise, i 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	1.0 is guaranteed to be	supported; others depend on the
     implementation.  The range	of supported widths and	the size difference
     between supported widths within the range can be queried by calling glGet
     with arguments GL_LINE_WIDTH_RANGE	and GL_LINE_WIDTH_GRANULARITY.

NOTES
     The line width specified by glLineWidth is	always returned	when
     GL_LINE_WIDTH is queried.	Clamping and rounding for aliased and
     antialiased lines have no effect on the specified value.

     Non-antialiased 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.





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glLineWidth(3G)		       OpenGL Reference		       glLineWidth(3G)



ERRORS
     GL_INVALID_VALUE is generated if width is less than or equal to zero.

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

ASSOCIATED GETS
     glGet with	argument GL_LINE_WIDTH
     glGet with	argument GL_LINE_WIDTH_RANGE
     glGet with	argument GL_LINE_WIDTH_GRANULARITY
     glIsEnabled with argument GL_LINE_SMOOTH


SEE ALSO
     glBlendFunc, glEnable, glHint








































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