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GLBITMAP(3G)				  OpenGL Manual 			     GLBITMAP(3G)

NAME
       glBitmap - draw a bitmap

C SPECIFICATION
       void glBitmap(GLsizei width, GLsizei height, GLfloat xorig, GLfloat yorig, GLfloat xmove,
		     GLfloat ymove, const GLubyte * bitmap);

PARAMETERS
       width, height
	   Specify the pixel width and height of the bitmap image.

       xorig, yorig
	   Specify the location of the origin in the bitmap image. The origin is measured from
	   the lower left corner of the bitmap, with right and up being the positive axes.

       xmove, ymove
	   Specify the x and y offsets to be added to the current raster position after the
	   bitmap is drawn.

       bitmap
	   Specifies the address of the bitmap image.

DESCRIPTION
       A bitmap is a binary image. When drawn, the bitmap is positioned relative to the current
       raster position, and frame buffer pixels corresponding to 1's in the bitmap are written
       using the current raster color or index. Frame buffer pixels corresponding to 0's in the
       bitmap are not modified.

       glBitmap takes seven arguments. The first pair specifies the width and height of the
       bitmap image. The second pair specifies the location of the bitmap origin relative to the
       lower left corner of the bitmap image. The third pair of arguments specifies x and y
       offsets to be added to the current raster position after the bitmap has been drawn. The
       final argument is a pointer to the bitmap image itself.

       If a non-zero named buffer object is bound to the GL_PIXEL_UNPACK_BUFFER target (see
       glBindBuffer()) while a bitmap image is specified, bitmap is treated as a byte offset into
       the buffer object's data store.

       The bitmap image is interpreted like image data for the glDrawPixels() command, with width
       and height corresponding to the width and height arguments of that command, and with type
       set to GL_BITMAP and format set to GL_COLOR_INDEX. Modes specified using glPixelStore()
       affect the interpretation of bitmap image data; modes specified using glPixelTransfer() do
       not.

       If the current raster position is invalid, glBitmap is ignored. Otherwise, the lower left
       corner of the bitmap image is positioned at the window coordinates

       x w = x r - x o

       y w = y r - y o

       where x r y r is the raster position and x o y o is the bitmap origin. Fragments are then
       generated for each pixel corresponding to a 1 (one) in the bitmap image. These fragments
       are generated using the current raster z coordinate, color or color index, and current
       raster texture coordinates. They are then treated just as if they had been generated by a
       point, line, or polygon, including texture mapping, fogging, and all per-fragment
       operations such as alpha and depth testing.

       After the bitmap has been drawn, the x and y coordinates of the current raster position
       are offset by xmove and ymove. No change is made to the z coordinate of the current raster
       position, or to the current raster color, texture coordinates, or index.

NOTES
       To set a valid raster position outside the viewport, first set a valid raster position
       inside the viewport, then call glBitmap with NULL as the bitmap parameter and with xmove
       and ymove set to the offsets of the new raster position. This technique is useful when
       panning an image around the viewport.

ERRORS
       GL_INVALID_VALUE is generated if width or height is negative.

       GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
       GL_PIXEL_UNPACK_BUFFER target and the buffer object's data store is currently mapped.

       GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
       GL_PIXEL_UNPACK_BUFFER target and the data would be unpacked from the buffer object such
       that the memory reads required would exceed the data store size.

       GL_INVALID_OPERATION is generated if glBitmap 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_COLOR

       glGet() with argument GL_CURRENT_RASTER_SECONDARY_COLOR

       glGet() with argument GL_CURRENT_RASTER_DISTANCE

       glGet() with argument GL_CURRENT_RASTER_INDEX

       glGet() with argument GL_CURRENT_RASTER_TEXTURE_COORDS

       glGet() with argument GL_CURRENT_RASTER_POSITION_VALID

       glGet() with argument GL_PIXEL_UNPACK_BUFFER_BINDING

SEE ALSO
       glBindBuffer(), glDrawPixels(), glPixelStore(), glPixelTransfer(), glRasterPos(),
       glWindowPos()

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI
       Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.

AUTHORS
       opengl.org

opengl.org				    06/10/2014				     GLBITMAP(3G)
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