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<STRONG>NAME</STRONG>
<STRONG>glPolygonStipple</STRONG> - set the polygon stippling pattern
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glPolygonStipple</STRONG>( const GLubyte *<EM>mask</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>mask</EM> Specifies a pointer to a 32x32 stipple pattern that
will be unpacked from memory in the same way that
<STRONG>glDrawPixels</STRONG> unpacks pixels.
<STRONG>DESCRIPTION</STRONG>
Polygon stippling, like line stippling (see <STRONG>glLineStipple</STRONG>),
masks out certain fragments produced by rasterization,
creating a pattern. Stippling is independent of polygon
antialiasing.
<EM>mask</EM> is a pointer to a 32x32 stipple pattern that is stored
in memory just like the pixel data supplied to a
<STRONG>glDrawPixels</STRONG> call with <EM>height</EM> and <EM>width</EM> both equal to 32, a
pixel format of <STRONG>GL_COLOR_INDEX</STRONG>, and data type of <STRONG>GL_BITMAP</STRONG>.
That is, the stipple pattern is represented as a 32x32 array
of 1-bit color indices packed in unsigned bytes.
<STRONG>glPixelStore</STRONG> parameters like <STRONG>GL_UNPACK_SWAP_BYTES</STRONG> and
<STRONG>GL_UNPACK_LSB_FIRST</STRONG> affect the assembling of the bits into a
stipple pattern. Pixel transfer operations (shift, offset,
pixel map) are not applied to the stipple image, however.
To enable and disable polygon stippling, call <STRONG>glEnable</STRONG> and
<STRONG>glDisable</STRONG> with argument <STRONG>GL_POLYGON_STIPPLE</STRONG>. Polygon
stippling is initially disabled. If it's enabled, a
rasterized polygon fragment with window coordinates x and
y is sent to the next stage of the GL if and only ifwthe
(<STRONG>x</STRONG> mod 32)th bit in the (y mod 32)th row of the stipple
pa<STRONG>t</STRONG>tern is 1 (one). When p<STRONG>o</STRONG>lygon stippling is disabled, it
is as if the stipple pattern consists of all 1's.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glPolygonStipple</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>glGetPolygonStipple</STRONG>
<STRONG>glIsEnabled</STRONG> with argument <STRONG>GL_POLYGON_STIPPLE</STRONG>
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>glDrawPixels</STRONG>, <STRONG>glLineStipple</STRONG>, <STRONG>glPixelStore</STRONG>, <STRONG>glPixelTransfer</STRONG>
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