*nix Documentation Project
·  Home
 +   man pages
·  Linux HOWTOs
·  FreeBSD Tips
·  *niX Forums

  man pages->IRIX man pages -> OpenGL/glbitmap (3)              


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

NAME    [Toc]    [Back]

     glBitmap -	draw a bitmap

C SPECIFICATION    [Toc]    [Back]

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

PARAMETERS    [Toc]    [Back]

     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    [Toc]    [Back]

     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.

     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  = |	x  - x	|
				  w	 r    o

									Page 1

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

				 y  = |	y  - y	|
				  w	 r    o

     where (x ,y ) is the raster position and (x ,y ) is the bitmap origin.
	     r	r				o  o
     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    [Toc]    [Back]

     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    [Toc]    [Back]

     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    [Toc]    [Back]

     glGet with	argument GL_CURRENT_RASTER_POSITION
     glGet with	argument GL_CURRENT_RASTER_COLOR
     glGet with	argument GL_CURRENT_RASTER_DISTANCE
     glGet with	argument GL_CURRENT_RASTER_INDEX

SEE ALSO    [Toc]    [Back]

     glDrawPixels, glPixelStore, glPixelTransfer, glRasterPos

									PPPPaaaaggggeeee 2222
[ Back ]
 Similar pages
Name OS Title
ufmGetBitmap IRIX get a character bitmap
ufmGetTransformedBitmap IRIX get a transformed character bitmap
bitmap Linux Define a new bitmap from a Tcl script
ufmFreeBitmap IRIX free a character bitmap
MrmFetchBitmapLiteral HP-UX Fetches a bitmap literal from a hierarchy
ipaint IRIX Paint using bitmap images as brushes
pbm IRIX portable bitmap file format
MrmFetchBitmapLiteral IRIX Fetches a bitmap literal from a hierarchy
MrmFetchBitmapLiteral Tru64 Fetches a bitmap literal from a hierarchy
pbm FreeBSD portable bitmap file format
Copyright © 2004-2005 DeniX Solutions SRL
newsletter delivery service