Index for Section 3G

Alphabetical listing for G

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glPolygonStipple(3G)
NAME
  glPolygonStipple - set the polygon stippling pattern

SYNOPSIS
  void glPolygonStipple(
	  const GLubyte *mask );

PARAMETERS
  mask
      Specifies a pointer to a 32 times 32 stipple pattern that will be
      unpacked from memory in the same way that glDrawPixels() unpacks
      pixels.

DESCRIPTION
  Polygon stippling, like line stippling (see glLineStipple()), masks out
  certain fragments produced by rasterization, creating a pattern. Stippling
  is independent of polygon antialiasing.

  mask is a pointer to a 32 times 32 stipple pattern that is stored in memory
  just like the pixel data supplied to a glDrawPixels() call with height and
  width both equal to 32, a pixel of GL_COLOR_INDEX, and data type of
  GL_BITMAP. That is, the stipple pattern is represented as a 32 times 32
  array of 1-bit color indices packed in unsigned bytes.  glPixelStore()
  parameters like GL_UNPACK_SWAP_BYTES and GL_UNPACK_LSB_FIRST affect the
  assembling of the bits into a stipple pattern. Pixel transfer operations
  (shift, offset, pixel map) are not applied to the stipple image, however.

  To enable and disable polygon stippling, call glEnable() and glDisable()
  with argument GL_POLYGON_STIPPLE. Polygon stippling is initially disabled.
  If it's enabled, a rasterized polygon fragment with window coordinates x[w]
  and y[w] is sent to the next stage of the GL if and only if the (x[w]
  mod32)th bit in the (y[w]mod32)th row of the stipple pattern is 1 (one).
  When polygon stippling is disabled, it is as if the stipple pattern
  consists of all 1's.

ERRORS
  GL_INVALID_OPERATION is generated if glPolygonStipple() is executed between
  the execution of glBegin() and the corresponding execution of glEnd().

ASSOCIATED GETS
       glGetPolygonStipple()
       glIsEnabled() with argument GL_POLYGON_STIPPLE

SEE ALSO
  glDrawPixels(3), glLineStipple(3), glPixelStore(3), glPixelTransfer(3)

Index for Section 3G

Alphabetical listing for G

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