AT&T UNIX™PC Unix System V Users Manual - tenox

WRASTOP ( 3T ) ( AT&T UNIX PC only ) WRASTOP ( 3T )
NAME
wrastop - pixel raster operations for bitmap displays
SYNOPSIS
#include
int wrastop(w, srcbase, srcwidth, dstbase, dstwidth,
srcx, srcy, dstx, dsty, width, height,
srcop, dstop, pattern)
int w;
unsigned short *srcbase, *dstbase, *pattern;
unsigned short srcwidth, dstwidth;
unsigned short srcx, srcy, dstx, dsty;
char srcop, dstop;
DESCRIPTION
The wrastop routine provides user programs with direct access to
a window 's pixel data. This "raster operation" is controlled by
the arguments which include both source and destination operators:
/* rastop source operators * /
#define SRCSRC 0 /* source * /
#define SRCPAT 1 /* pattern */
#define SRCAND 2 /* source and pattern * /
#define SRCOR 3 /* source or pattern * /
#define SRCXOR 4 /* source xor pattern * /
/* rastop destination operators * /
#define DSTSRC 0 /* srcop(src) * /
#define DSTAND 1 /* srcop(src) and dst * J
#define DSTOR 2 /* srcop( src) or dst * /
#define DSTXOR 3 /* srcop(src) xor dst * /
#define DSTCAM 4 /* not(srcop) and dst */
W is the window identifier for the window to be accessed (see
tam(3T) for more information on window identifiers). The
srcbase and dstbase arguments determine the memory addresses
of the source and destination planes. Srcbase and dstbase may
point to the address of the first short of an arbitrarily-sized array
of shorts. Each row of pixels consists of srcwidth (or dstwidth )
number of bytes from this array. Thus, the first pixel row exists
from srcbase to ((char *)srcbase) + srcwidth . Within each short,
the least significant bit is the left-most when displayed on the
screen.
Alternatively, srcbase and/or dstbase may contain 0, in which
case the source or destination is assumed to be the window
specified by the first arg to the call. The caller need not supply
any value for the srcwidth if srcbase is 0, nor dstwidth if dstbase
is zero. It is therefore possible to perform raster operations from
user space to user space, user space to screen, screen to user space,
or screen to screen.
The srcx, srcy, dstx , and dsty parameters contain pixel addresses
within the specified pixel plane. 0,0 is always the upper-left-hand
corner of the display. Note that raster operations are completely
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