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GLPOLYGONOFFSET(3G)                              OpenGL 3.3                              GLPOLYGONOFFSET(3G)



NAME
       glPolygonOffset - set the scale and units used to calculate depth values

C SPECIFICATION
       void glPolygonOffset(GLfloat factor, GLfloat units);

PARAMETERS
       factor
           Specifies a scale factor that is used to create a variable depth offset for each polygon. The
           initial value is 0.

       units
           Is multiplied by an implementation-specific value to create a constant depth offset. The initial
           value is 0.

DESCRIPTION
       When GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, or GL_POLYGON_OFFSET_POINT is enabled, each
       fragment's depth value will be offset after it is interpolated from the depth values of the
       appropriate vertices. The value of the offset is factor x DZ + r x units, where DZ is a measurement
       of the change in depth relative to the screen area of the polygon, and r is the smallest value that
       is guaranteed to produce a resolvable offset for a given implementation. The offset is added before
       the depth test is performed and before the value is written into the depth buffer.


       glPolygonOffset is useful for rendering hidden-line images, for applying decals to surfaces, and for
       rendering solids with highlighted edges.

ASSOCIATED GETS
       glIsEnabled() with argument GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, or
       GL_POLYGON_OFFSET_POINT.


       glGet() with argument GL_POLYGON_OFFSET_FACTOR or GL_POLYGON_OFFSET_UNITS.

SEE ALSO
       glDepthFunc(), glEnable(), glGet(), glIsEnabled()


COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software
       B License. For details, see http://oss.sgi.com/projects/FreeB/.



OpenGL 3.3                                       03/08/2011                              GLPOLYGONOFFSET(3G)