Index for Section 3G

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glPolygonMode(3G)
NAME
  glPolygonMode - select a polygon rasterization mode

SYNOPSIS
  void glPolygonMode(
	  GLenum face,
	  GLenum mode );

PARAMETERS
  face
      Specifies the polygons that mode applies to. Must be GL_FRONT for
      front-facing polygons, GL_BACK for back-facing polygons, or
      GL_FRONT_AND_BACK for front- and back-facing polygons.

  mode
      Specifies how polygons will be rasterized. Accepted values are
      GL_POINT, GL_LINE, and GL_FILL. The initial value is GL_FILL for both
      front- and back-facing polygons.

DESCRIPTION
  glPolygonMode() controls the interpretation of polygons for rasterization.
  face describes which polygons mode applies to: front-facing polygons
  (GL_FRONT), back-facing polygons (GL_BACK), or both (GL_FRONT_AND_BACK).
  The polygon mode affects only the final rasterization of polygons.  In
  particular, a polygon's vertices are lit and the polygon is clipped and
  possibly culled before these modes are applied.

  Three modes are defined and can be specified in mode:

  GL_POINT
      Polygon vertices that are marked as the start of a boundary edge are
      drawn as points. Point attributes such as GL_POINT_SIZE and
      GL_POINT_SMOOTH control the rasterization of the points. Polygon
      rasterization attributes other than GL_POLYGON_MODE have no effect.

  GL_LINE
      Boundary edges of the polygon are drawn as line segments. They are
      treated as connected line segments for line stippling; the line stipple
      counter and pattern are not reset between segments (see
      glLineStipple()). Line attributes such as GL_LINE_WIDTH and
      GL_LINE_SMOOTH control the rasterization of the lines. Polygon
      rasterization attributes other than GL_POLYGON_MODE have no effect.

  GL_FILL
      The interior of the polygon is filled. Polygon attributes such as
      GL_POLYGON_STIPPLE and GL_POLYGON_SMOOTH control the rasterization of
      the polygon.

NOTES
  Vertices are marked as boundary or nonboundary with an edge option.  Edge
  options are generated internally by the GL when it decomposes polygons;
  they can be set explicitly using glEdgeFlag().

ERRORS
  GL_INVALID_ENUM is generated if either face or mode is not an accepted
  value.

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

ASSOCIATED GETS
  glGet() with argument GL_POLYGON_MODE

EXAMPLES
  To draw a surface with filled back-facing polygons and outlined front-
  facing polygons, call

       glPolygonMode(GL_FRONT, GL_LINE);

SEE ALSO
  glBegin(3), glEdgeFlag(3), glLineStipple(3), glLineWidth(3),
  glPointSize(3), glPolygonStipple(3)

Index for Section 3G

Alphabetical listing for G

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