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GLRASTERPOS()							   GLRASTERPOS()

NAME
     glRasterPos2d,  glRasterPos2f, glRasterPos2i, glRasterPos2s, glRasterPos3d,
     glRasterPos3f, glRasterPos3i, glRasterPos3s, glRasterPos4d,  glRasterPos4f,
     glRasterPos4i,  glRasterPos4s,  glRasterPos2dv,  glRasterPos2fv,  glRaster-
     Pos2iv,  glRasterPos2sv,  glRasterPos3dv,	glRasterPos3fv,  glRasterPos3iv,
     glRasterPos3sv,  glRasterPos4dv,  glRasterPos4fv, glRasterPos4iv, glRaster-
     Pos4sv - 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  op-
     erations.	It  is maintained with subpixel accuracy.  See glBitmap, glDraw-
     Pixels, 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  $w$  explic-
     itly.   glRasterPos3  specifies object coordinate $x$, $y$, and $z$ explic-
     itly, 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 modelview and
     projection matrices and passed to the clipping stage.  If the vertex is not
     culled, then it is projected and scaled to window coordinates, 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 associated 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_CURRENT_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 vari-
     able 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 gen-
     eration functions (see glTexGen).	Finally, the distance from the origin of
     the eye coordinate system to the vertex as transformed  by  only  the  mod-
     elview 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_CURRENT_RASTER_INDEX is  always  1;  in
     color  index  mode, the current raster RGBA color always maintains its ini-
     tial 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  result  in
     changes to GL state).

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

     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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