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GLRASTERPOS()							 GLRASTERPOS()

NAME
       glRasterPos2d,  glRasterPos2f,  glRasterPos2i, glRasterPos2s, glRaster-
       Pos3d,  glRasterPos3f,  glRasterPos3i,  glRasterPos3s,	glRasterPos4d,
       glRasterPos4f,  glRasterPos4i, glRasterPos4s, glRasterPos2dv, glRaster-
       Pos2fv, glRasterPos2iv, glRasterPos2sv, glRasterPos3dv, glRasterPos3fv,
       glRasterPos3iv,	 glRasterPos3sv,    glRasterPos4dv,    glRasterPos4fv,
       glRasterPos4iv,	glRasterPos4sv - specify the raster position for pixel
       operations

C SPECIFICATION
       void glRasterPos2d( GLdouble x,
			   GLdouble y )
       void glRasterPos2f( GLfloat x,
			   GLfloat y )
       void glRasterPos2i( GLint x,
			   GLint y )
       void glRasterPos2s( GLshort x,
			   GLshort y )
       void glRasterPos3d( GLdouble x,
			   GLdouble y,
			   GLdouble z )
       void glRasterPos3f( GLfloat x,
			   GLfloat y,
			   GLfloat z )
       void glRasterPos3i( GLint x,
			   GLint y,
			   GLint z )
       void glRasterPos3s( GLshort x,
			   GLshort y,
			   GLshort z )
       void glRasterPos4d( GLdouble x,
			   GLdouble y,
			   GLdouble z,
			   GLdouble w )
       void glRasterPos4f( GLfloat x,
			   GLfloat y,
			   GLfloat z,
			   GLfloat w )
       void glRasterPos4i( GLint x,
			   GLint y,
			   GLint z,
			   GLint w )
       void glRasterPos4s( GLshort x,
			   GLshort y,
			   GLshort z,
			   GLshort w )

       delim $$

PARAMETERS
       x, y, z,	w
		Specify	the $x$, $y$, $z$,  and	 $w$  object  coordinates  (if
		present) for the raster	position.

C SPECIFICATION
       void glRasterPos2dv( const GLdouble *v )
       void glRasterPos2fv( const GLfloat *v )
       void glRasterPos2iv( const GLint	*v )
       void glRasterPos2sv( const GLshort *v )
       void glRasterPos3dv( const GLdouble *v )
       void glRasterPos3fv( const GLfloat *v )
       void glRasterPos3iv( const GLint	*v )
       void glRasterPos3sv( const GLshort *v )
       void glRasterPos4dv( const GLdouble *v )
       void glRasterPos4fv( const GLfloat *v )
       void glRasterPos4iv( const GLint	*v )
       void glRasterPos4sv( const GLshort *v )

PARAMETERS
       v      Specifies	a pointer to an	array of two, three, or	four elements,
	      specifying $x$, $y$, $z$,	and $w$	coordinates, respectively.

DESCRIPTION
       The  GL	maintains a 3D position	in window coordinates.	This position,
       called the raster position, is used to position pixel and bitmap	 write
       operations. It is maintained with subpixel accuracy.  See glBitmap, gl-
       DrawPixels, and glCopyPixels.

       The  current raster position consists of	three window coordinates ($x$,
       $y$, $z$), a clip coordinate value ($w$), an eye	coordinate distance, a
       valid bit, and associated color data and	texture	coordinates.  The  $w$
       coordinate is a clip coordinate,	because	$w$ is not projected to	window
       coordinates.   glRasterPos4 specifies object coordinates	$x$, $y$, $z$,
       and $w$ explicitly.  glRasterPos3 specifies object coordinate $x$, $y$,
       and $z$ explicitly, while $w$ is	implicitly  set	 to  1.	  glRasterPos2
       uses  the  argument values for $x$ and $y$ while	implicitly setting $z$
       and $w$ to 0 and	1.

       The object coordinates presented	by glRasterPos are treated  just  like
       those  of  a glVertex command: They are transformed by the current mod-
       elview and projection matrices and passed to the	 clipping  stage.   If
       the vertex is not culled, then it is projected and scaled to window co-
       ordinates,  which  become  the  new  current  raster  position, and the
       GL_CURRENT_RASTER_POSITION_VALID	flag is	set.  If the vertex is culled,
       then the	valid bit is cleared and the current raster position and asso-
       ciated color and	texture	coordinates are	undefined.

       The current raster position also	includes some  associated  color  data
       and   texture  coordinates.   If	 lighting  is  enabled,	 then  GL_CUR-
       RENT_RASTER_COLOR (in RGBA mode)	or GL_CURRENT_RASTER_INDEX  (in	 color
       index  mode)  is	 set to	the color produced by the lighting calculation
       (see glLight, glLightModel, and
       glShadeModel).  If lighting is disabled,	current	color (in  RGBA	 mode,
       state  variable	GL_CURRENT_COLOR) or color index (in color index mode,
       state variable GL_CURRENT_INDEX)	is used	to update the  current	raster
       color.

       Likewise,  GL_CURRENT_RASTER_TEXTURE_COORDS is updated as a function of
       GL_CURRENT_TEXTURE_COORDS, based	on the texture matrix and the  texture
       generation  functions  (see  glTexGen).	Finally, the distance from the
       origin of the eye coordinate system to the  vertex  as  transformed  by
       only the	modelview matrix replaces GL_CURRENT_RASTER_DISTANCE.

       Initially,  the	current	 raster	 position is (0, 0, 0, 1), the current
       raster distance is 0, the valid bit is set, the associated  RGBA	 color
       is  (1,	1,  1, 1), the associated color	index is 1, and	the associated
       texture	coordinates  are  (0,  0,  0,  1).   In	 RGBA  mode,   GL_CUR-
       RENT_RASTER_INDEX  is always 1; in color	index mode, the	current	raster
       RGBA color always maintains its initial value.

NOTES
       The raster position is modified both by glRasterPos and by glBitmap.

       When the	raster position	coordinates are	invalid, drawing commands that
       are based on the	raster position	are ignored (that is, they do not  re-
       sult in changes to GL state).

       Calling	glDrawElements may leave the current color or index indetermi-
       nate.  If glRasterPos is	executed while the current color or  index  is
       indeterminate, the current raster color or current raster index remains
       indeterminate.

       To  set a valid raster position outside the viewport, first set a valid
       raster position,	then call glBitmap with	NULL as	the bitmap parameter.

ERRORS
       GL_INVALID_OPERATION is generated if glRasterPos	 is  executed  between
       the execution of	glBegin	and the	corresponding execution	of glEnd.

ASSOCIATED GETS
       glGet with argument GL_CURRENT_RASTER_POSITION
       glGet with argument GL_CURRENT_RASTER_POSITION_VALID
       glGet with argument GL_CURRENT_RASTER_DISTANCE
       glGet with argument GL_CURRENT_RASTER_COLOR
       glGet with argument GL_CURRENT_RASTER_INDEX
       glGet with argument GL_CURRENT_RASTER_TEXTURE_COORDS

SEE ALSO
       glBitmap, glCopyPixels, glDrawElements, glDrawPixels, glLight, glLight-
       Model, glShadeModel, glTexCoord,	glTexGen, glVertex

								 GLRASTERPOS()

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