Section: Misc. Reference Manual Pages (3G)
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- set the polygon stippling pattern
const GLubyte *mask )
Specifies a pointer to a $32 ~times~ 32$ stipple pattern that will be unpacked
from memory in the same way that glDrawPixels unpacks pixels.
like line stippling
masks out certain fragments produced by rasterization,
creating a pattern.
Stippling is independent of polygon antialiasing.
mask is a pointer to a $32 ~times~ 32$ stipple pattern that is stored
in memory just like the pixel data supplied to a glDrawPixels
both equal to 32, a pixel
of GL_COLOR_INDEX, and data type
the stipple pattern is represented as a $32 ~times~ 32$ array
of 1-bit color indices packed in unsigned bytes.
glPixelStore parameters like GL_UNPACK_SWAP_BYTES
and GL_UNPACK_LSB_FIRST affect the assembling of the bits into a
Pixel transfer operations
(shift, offset, pixel map)
are not applied to the stipple image,
To enable and disable polygon stippling, call
glEnable and glDisable
with argument GL_POLYGON_STIPPLE. Polygon stippling is initially
disabled. If it's enabled,
a rasterized polygon fragment with window coordinates $x sub w$ and $y sub w$
is sent to the next stage of the GL if and only if the
($x sub w~roman mod~32$)th bit in the ($y sub w~roman mod~32$)th row
of the stipple pattern is 1 (one).
When polygon stippling is disabled, it is as if the stipple pattern
consists of all 1's.
GL_INVALID_OPERATION is generated if glPolygonStipple
is executed between the execution of glBegin
and the corresponding execution of glEnd.
glIsEnabled with argument GL_POLYGON_STIPPLE
- C SPECIFICATION
- ASSOCIATED GETS
- SEE ALSO
linux.jgfs.net manual pages