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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,  glCopyTexSubIm-
     age2D,  glDrawPixels, glReadPixels, glTexImage1D, glTexImage2D, glTexSubIm-
     age1D, 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 components.

     GL_PIXEL_MAP_B_TO_B	   Maps blue components to blue components.

     GL_PIXEL_MAP_A_TO_A	   Maps alpha components to alpha components.

     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 un-
     specified mantissa and exponent sizes.  Floating-point values specified  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 converted 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,  re-
     tain their values in fixed-point format, with an unspecified number of bits
     to  the  right  of  the  binary  point.  Floating-point values specified by
     glPixelMapfv are converted directly to the internal fixed-point  format  of
     these  maps.  Unsigned integer values specified by glPixelMapusv and glPix-
     elMapuiv 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 deter-
     mined  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 ex-
     ecution 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, glRead-
     Pixels, glTexImage1D, glTexImage2D, glTexSubImage1D, glTexSubImage2D

								    GLPIXELMAP()

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=glPixelMapuiv&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

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