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GLRASTERPOS(3G)                                                                              GLRASTERPOS(3G)



NAME
       glRasterPos2d,  glRasterPos2f,  glRasterPos2i, glRasterPos2s, glRasterPos3d, glRasterPos3f, glRaster-Pos3i, glRasterPos3i,
       Pos3i, glRasterPos3s, glRasterPos4d,  glRasterPos4f,  glRasterPos4i,  glRasterPos4s,  glRasterPos2dv,
       glRasterPos2fv,   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 )


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, glDrawPixels, 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 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 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 dis-tance distance
       tance 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 asso-ciated associated
       ciated  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 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 posi-tion position
       tion are ignored (that is, they do not result in changes to GL state).

       Calling  glDrawElements,  or  glDrawRangeElements may leave the current color or index indeterminate.
       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.

       When the GL_ARB_imaging extension is supported, there are distinct  raster  texture  coordinates  for
       each texture unit. Each texture unit's current raster texture coordinates are updated by glRasterPos.

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(3G),  glCopyPixels(3G), glDrawArrays(3G), glDrawElements(3G), glDrawRangeElements(3G), glDrawPixels(3G), glTexCoord(3G),
       glTexGen(3G), glVertex(3G)




                                                                                             GLRASTERPOS(3G)