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GLPOLYGONMODE(3G)                                                                          GLPOLYGONMODE(3G)



NAME
       glPolygonMode - select a polygon rasterization mode


C SPECIFICATION
       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 poly-gons polygons
       gons mode applies to: front-facing polygons (GL_FRONT), back-facing polygons (GL_BACK),  or  both  (-GL_FRONT_AND_BACK). (GL_FRONT_AND_BACK).
       GL_FRONT_AND_BACK).   The polygon mode affects only the final rasterization of polygons.  In particu-lar, particular,
       lar, 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  con-nected connected
                     nected  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.

EXAMPLES
       To  draw  a  surface  with  filled  back-facing  polygons  and  outlined  front-facing polygons, call
       glPolygonMode(GL_FRONT, GL_LINE);

NOTES
       Vertices are marked as boundary or nonboundary with an edge flag.  Edge flags  are  generated  inter-nally internally
       nally 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

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




                                                                                           GLPOLYGONMODE(3G)