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GLLINESTIPPLE(3G)                                                                          GLLINESTIPPLE(3G)



NAME
       glLineStipple - specify the line stipple pattern


C SPECIFICATION
       void glLineStipple( GLint factor,
                           GLushort pattern )


PARAMETERS
       factor   Specifies  a multiplier for each bit in the line stipple pattern.  If factor is 3, for exam-ple, example,
                ple, each bit in the pattern is used three times before the next bit in the pattern is used.
                factor is clamped to the range [1, 256] and defaults to 1.

       pattern  Specifies  a  16-bit  integer whose bit pattern determines which fragments of a line will be
                drawn when the line is rasterized.  Bit zero is used first; the default pattern is all  1's.

DESCRIPTION
       Line  stippling  masks  out  certain fragments produced by rasterization; those fragments will not be
       drawn.  The masking is achieved by using three parameters: the 16-bit line stipple  pattern  pattern,
       the repeat count factor, and an integer stipple counter s.

       Counter  s  is  reset  to  0  whenever glBegin is called, and before each line segment of a glBegin(-GL_LINES)/glEnd glBegin(GL_LINES)/glEnd
       GL_LINES)/glEnd sequence is generated.  It is incremented after each fragment of a unit width aliased
       line segment is generated, or after each i fragments of an i width line segment are generated.  The i
       fragments associated with count s are masked out if

                                          pattern bit (s / factor) mod 16

       is 0, otherwise these fragments are sent to the frame buffer.  Bit zero of pattern is the least  sig-nificant significant
       nificant bit.

       Antialiased  lines  are  treated  as  a  sequence  of 1 * width rectangles for purposes of stippling.
       Whether rectagle s is rasterized or not depends on the fragment rule  described  for  aliased  lines,
       counting rectangles rather than groups of fragments.

       To  enable  and  disable  line  stippling, call glEnable and glDisable with argument GL_LINE_STIPPLE.
       When enabled, the line stipple pattern is applied as described above.  When disabled, it is as if the
       pattern were all 1's.  Initially, line stippling is disabled.

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

ASSOCIATED GETS
       glGet with argument GL_LINE_STIPPLE_PATTERN
       glGet with argument GL_LINE_STIPPLE_REPEAT
       glIsEnabled with argument GL_LINE_STIPPLE

SEE ALSO
       glLineWidth(3G), glPolygonStipple(3G)




                                                                                           GLLINESTIPPLE(3G)