Index for Section 3G

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glLineStipple(3G)
NAME
  glLineStipple - specify the line stipple pattern

SYNOPSIS
  void glLineStipple(
	  GLint factor,
	  GLushort pattern );

PARAMETERS
  factor
      Specifies a multiplier for each bit in the line stipple pattern. If
      factor is 3, for example, 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() 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 significant bit.

  Antialiased lines are treated as a sequence of 1 times 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(3), glPolygonStipple(3)

Index for Section 3G

Alphabetical listing for G

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