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<STRONG>NAME</STRONG>
<STRONG>glBitmap</STRONG> - draw a bitmap
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glBitmap</STRONG>( GLsizei <EM>width</EM>,
GLsizei <EM>height</EM>,
GLfloat <EM>xorig</EM>,
GLfloat <EM>yorig</EM>,
GLfloat <EM>xmove</EM>,
GLfloat <EM>ymove</EM>,
const GLubyte *<EM>bitmap</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>width</EM>, <EM>height</EM> Specify the pixel width and height of the
bitmap image.
<EM>xorig</EM>, <EM>yorig</EM> 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.
<EM>xmove</EM>, <EM>ymove</EM> Specify the <EM>x</EM> and <EM>y</EM> offsets to be added to the
current raster position after the bitmap is
drawn.
<EM>bitmap</EM> Specifies the address of the bitmap image.
<STRONG>DESCRIPTION</STRONG>
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.
<STRONG>glBitmap</STRONG> 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 <EM>x</EM> and <EM>y</EM> 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
<STRONG>glDrawPixels</STRONG> command, with <EM>width</EM> and <EM>height</EM> corresponding to
the width and height arguments of that command, and with
<EM>type</EM> set to <STRONG>GL_BITMAP</STRONG> and <EM>format</EM> set to <STRONG>GL_COLOR_INDEX</STRONG>.
Modes specified using <STRONG>glPixelStore</STRONG> affect the interpretation
of bitmap image data; modes specified using <STRONG>glPixelTransfer</STRONG>
do not.
If the current raster position is invalid, <STRONG>glBitmap</STRONG> is
ignored. Otherwise, the lower left corner of the bitmap
image is positioned at the window coordinates
x = | x - x |
w r o
y = | y - y |
w r o
where (x ,y ) is the raster position and (x ,y ) is the
bitmap o<STRONG>r</STRONG>ig<STRONG>i</STRONG>n. Fragments are then generate<STRONG>d</STRONG> f<STRONG>o</STRONG>r each pixel
corresponding to a 1 (one) in the bitmap image. These
fragments are generated using the current raster <EM>z</EM>
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 <EM>x</EM> and <EM>y</EM> coordinates of
the current raster position are offset by <EM>xmove</EM> and <EM>ymove</EM>.
No change is made to the <EM>z</EM> coordinate of the current raster
position, or to the current raster color, texture
coordinates, or index.
<STRONG>NOTES</STRONG>
To set a valid raster position outside the viewport, first
set a valid raster position inside the viewport, then call
<STRONG>glBitmap</STRONG> with NULL as the <EM>bitmap</EM> parameter and with <EM>xmove</EM>
and <EM>ymove</EM> set to the offsets of the new raster position.
This technique is useful when panning an image around the
viewport.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>width</EM> or <EM>height</EM> is
negative.
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glBitmap</STRONG> is executed
between the execution of <STRONG>glBegin</STRONG> and the corresponding
execution of <STRONG>glEnd</STRONG>.
<STRONG>ASSOCIATED</STRONG> <STRONG>GETS</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_CURRENT_RASTER_POSITION</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_CURRENT_RASTER_COLOR</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_CURRENT_RASTER_INDEX</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_CURRENT_RASTER_TEXTURE_COORDS</STRONG>
<STRONG>glGet</STRONG> with argument <STRONG>GL_CURRENT_RASTER_POSITION_VALID</STRONG>
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>glDrawPixels</STRONG>, <STRONG>glPixelStore</STRONG>, <STRONG>glPixelTransfer</STRONG>, <STRONG>glRasterPos</STRONG>
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