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GLPIXELMAP()							  GLPIXELMAP()

NAME
       glPixelMapfv, glPixelMapuiv, glPixelMapusv - set	up pixel transfer maps

C SPECIFICATION
       void glPixelMapfv( GLenum map,
			  GLsizei mapsize,
			  const	GLfloat	*values	)
       void glPixelMapuiv( GLenum map,
			   GLsizei mapsize,
			   const GLuint	*values	)
       void glPixelMapusv( GLenum map,
			   GLsizei mapsize,
			   const GLushort *values )

       delim $$

PARAMETERS
       map	Specifies a symbolic map name.	Must be	one of the following:
		GL_PIXEL_MAP_I_TO_I, GL_PIXEL_MAP_S_TO_S, GL_PIXEL_MAP_I_TO_R,
		GL_PIXEL_MAP_I_TO_G, GL_PIXEL_MAP_I_TO_B, GL_PIXEL_MAP_I_TO_A,
		GL_PIXEL_MAP_R_TO_R, GL_PIXEL_MAP_G_TO_G, GL_PIXEL_MAP_B_TO_B,
		or GL_PIXEL_MAP_A_TO_A.

       mapsize	Specifies the size of the map being defined.

       values	Specifies an array of mapsize values.

DESCRIPTION
       glPixelMap  sets	 up translation	tables,	or maps, used by glCopyPixels,
       glCopyTexImage1D,  glCopyTexImage2D,  glCopyTexSubImage1D,   glCopyTex-
       SubImage2D, glDrawPixels, glReadPixels, glTexImage1D, glTexImage2D, gl-
       TexSubImage1D,  and  glTexSubImage2D.   Use  of these maps is described
       completely in the glPixelTransfer reference page,  and  partly  in  the
       reference  pages	 for  the  pixel and texture image commands.  Only the
       specification of	the maps is described in this reference	page.

       map is a	symbolic map name, indicating one of ten maps to set.  mapsize
       specifies the number of entries in the map, and values is a pointer  to
       an array	of mapsize map values.

       The ten maps are	as follows:

       GL_PIXEL_MAP_I_TO_I	     Maps color	indices	to color indices.

       GL_PIXEL_MAP_S_TO_S	     Maps stencil indices to stencil indices.

       GL_PIXEL_MAP_I_TO_R	     Maps color	indices	to red components.

       GL_PIXEL_MAP_I_TO_G	     Maps color	indices	to green components.

       GL_PIXEL_MAP_I_TO_B	     Maps color	indices	to blue	components.

       GL_PIXEL_MAP_I_TO_A	     Maps color	indices	to alpha components.

       GL_PIXEL_MAP_R_TO_R	     Maps red components to red	components.

       GL_PIXEL_MAP_G_TO_G	     Maps  green  components  to  green	compo-
				     nents.

       GL_PIXEL_MAP_B_TO_B	     Maps blue components to blue components.

       GL_PIXEL_MAP_A_TO_A	     Maps alpha	 components  to	 alpha	compo-
				     nents.

       The  entries  in	 a  map	can be specified as single-precision floating-
       point numbers, unsigned short  integers,	 or  unsigned  long  integers.
       Maps that store color component values (all but GL_PIXEL_MAP_I_TO_I and
       GL_PIXEL_MAP_S_TO_S) retain their values	in floating-point format, with
       unspecified  mantissa and exponent sizes.  Floating-point values	speci-
       fied by glPixelMapfv are	converted directly to the  internal  floating-
       point  format of	these maps, then clamped to the	range [0,1].  Unsigned
       integer values specified	by glPixelMapusv and  glPixelMapuiv  are  con-
       verted  linearly	 such  that  the largest representable integer maps to
       1.0, and	0 maps to 0.0.

       Maps that store indices,	GL_PIXEL_MAP_I_TO_I  and  GL_PIXEL_MAP_S_TO_S,
       retain  their  values in	fixed-point format, with an unspecified	number
       of bits to the right of the binary point.  Floating-point values	speci-
       fied by glPixelMapfv are	converted directly to the internal fixed-point
       format of these maps.  Unsigned integer values specified	by  glPixelMa-
       pusv  and  glPixelMapuiv	 specify  integer  values, with	all 0's	to the
       right of	the binary point.

       The following table shows the initial sizes and values for each of  the
       maps.   Maps  that  are indexed by either color or stencil indices must
       have mapsize = $2 sup n$	for some $n$ or	 the  results  are  undefined.
       The  maximum  allowable size for	each map depends on the	implementation
       and   can   be	determined   by	  calling    glGet    with    argument
       GL_MAX_PIXEL_MAP_TABLE.	 The single maximum applies to all maps; it is
       at least	32.
+---------------------+----------------+----------------+--------------+---------------+
|	  map	      |	 lookup	index  |  lookup value	| initial size | initial value |
+---------------------+----------------+----------------+--------------+---------------+
| GL_PIXEL_MAP_I_TO_I |	 color index   |  color	index	|      1       |       0       |
| GL_PIXEL_MAP_S_TO_S |	stencil	index  | stencil index	|      1       |       0       |
| GL_PIXEL_MAP_I_TO_R |	 color index   |       R	|      1       |       0       |
| GL_PIXEL_MAP_I_TO_G |	 color index   |       G	|      1       |       0       |
| GL_PIXEL_MAP_I_TO_B |	 color index   |       B	|      1       |       0       |
| GL_PIXEL_MAP_I_TO_A |	 color index   |       A	|      1       |       0       |
| GL_PIXEL_MAP_R_TO_R |	      R	       |       R	|      1       |       0       |
| GL_PIXEL_MAP_G_TO_G |	      G	       |       G	|      1       |       0       |
| GL_PIXEL_MAP_B_TO_B |	      B	       |       B	|      1       |       0       |
| GL_PIXEL_MAP_A_TO_A |	      A	       |       A	|      1       |       0       |
+---------------------+----------------+----------------+--------------+---------------+

ERRORS
       GL_INVALID_ENUM is generated if map is not an accepted value.

       GL_INVALID_VALUE	is generated if	mapsize	is less	 than  one  or	larger
       than GL_MAX_PIXEL_MAP_TABLE.

       GL_INVALID_VALUE	  is   generated   if	map   is  GL_PIXEL_MAP_I_TO_I,
       GL_PIXEL_MAP_S_TO_S,	GL_PIXEL_MAP_I_TO_R,	  GL_PIXEL_MAP_I_TO_G,
       GL_PIXEL_MAP_I_TO_B, or GL_PIXEL_MAP_I_TO_A, and	mapsize	is not a power
       of two.

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

ASSOCIATED GETS
       glGetPixelMap
       glGet with argument GL_PIXEL_MAP_I_TO_I_SIZE
       glGet with argument GL_PIXEL_MAP_S_TO_S_SIZE
       glGet with argument GL_PIXEL_MAP_I_TO_R_SIZE
       glGet with argument GL_PIXEL_MAP_I_TO_G_SIZE
       glGet with argument GL_PIXEL_MAP_I_TO_B_SIZE
       glGet with argument GL_PIXEL_MAP_I_TO_A_SIZE
       glGet with argument GL_PIXEL_MAP_R_TO_R_SIZE
       glGet with argument GL_PIXEL_MAP_G_TO_G_SIZE
       glGet with argument GL_PIXEL_MAP_B_TO_B_SIZE
       glGet with argument GL_PIXEL_MAP_A_TO_A_SIZE
       glGet with argument GL_MAX_PIXEL_MAP_TABLE

SEE ALSO
       glCopyPixels,  glCopyTexImage1D,	glCopyTexImage2D, glCopyTexSubImage1D,
       glCopyTexSubImage2D,   glDrawPixels,   glPixelStore,   glPixelTransfer,
       glReadPixels,  glTexImage1D, glTexImage2D, glTexSubImage1D, glTexSubIm-
       age2D

								  GLPIXELMAP()

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