glBitmap(3G)		       OpenGL Reference			  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 ones in the bitmap are written using the current raster
     color or index.  Frame buffer pixels corresponding	to zeros in the	bitmap
     are not modified.

     glBitmap takes seven arguments.  The first	pair specify the width and
     height of the bitmap image.  The second pair specify the location of the
     bitmap origin relative to the lower left corner of	the bitmap image.  The
     third pair	of arguments specify 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.

     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.





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glBitmap(3G)		       OpenGL Reference			  glBitmap(3G)



     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

				 xw = |	xr - xo	|

				 yw = |	yr - yo	|

     where (xr,yr) is the raster position and (xo,yo) is the bitmap origin.
     Fragments are then	generated for each pixel corresponding to a 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, index, or texture coordinates.

ERRORS
     GL_INVALID_VALUE is generated if width or height is negative.

     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_INDEX
     glGet with	argument GL_CURRENT_RASTER_TEXTURE_COORDS
     glGet with	argument GL_CURRENT_RASTER_POSITION_VALID


SEE ALSO
     glDrawPixels, glRasterPos,	glPixelStore, glPixelTransfer


















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