XDrawLine(3X) XDrawLine(3X)
NAME
XDrawLine, XDrawLines, XDrawSegments - draw lines and
polygons
SYNOPSIS
XDrawLine(display, d, gc, x1, y1, x2, y2)
Display *display;
Drawable d;
GC gc;
int x1, y1, x2, y2;
XDrawLines(display, d, gc, points, npoints, mode)
Display *display;
Drawable d;
GC gc;
XPoint *points;
int npoints;
int mode;
XDrawSegments(display, d, gc, segments, nsegments)
Display *display;
Drawable d;
GC gc;
XSegment *segments;
int nsegments;
ARGUMENTS
d Specifies the drawable.
display Specifies the connection to the X server.
gc Specifies the GC.
mode Specifies the coordinate mode. You can pass
CoordModeOrigin or CoordModePrevious.
npoints Specifies the number of points in the array.
nsegments Specifies the number of segments in the
array.
points Specifies a pointer to an array of points.
segments Specifies a pointer to an array of segments.
x1
y1
x2
y2 Specify the points (x1, y1) and (x2, y2) to
be connected.
DESCRIPTION
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XDrawLine(3X) XDrawLine(3X)
The XDrawLine function uses the components of the
specified GC to draw a line between the specified set
of points (x1, y1) and (x2, y2). It does not perform
joining at coincident endpoints. For any given line,
XDrawLine does not draw a pixel more than once. If
lines intersect, the intersecting pixels are drawn
multiple times.
The XDrawLines function uses the components of the
specified GC to draw npoints-1 lines between each pair
of points (point[i], point[i+1]) in the array of XPoint
structures. It draws the lines in the order listed in
the array. The lines join correctly at all
intermediate points, and if the first and last points
coincide, the first and last lines also join correctly.
For any given line, XDrawLines does not draw a pixel
more than once. If thin (zero line-width) lines
intersect, the intersecting pixels are drawn multiple
times. If wide lines intersect, the intersecting
pixels are drawn only once, as though the entire
PolyLine protocol request were a single, filled shape.
CoordModeOrigin treats all coordinates as relative to
the origin, and CoordModePrevious treats all
coordinates after the first as relative to the previous
point.
The XDrawSegments function draws multiple, unconnected
lines. For each segment, XDrawSegments draws a line
between (x1, y1) and (x2, y2). It draws the lines in
the order listed in the array of XSegment structures
and does not perform joining at coincident endpoints.
For any given line, XDrawSegments does not draw a pixel
more than once. If lines intersect, the intersecting
pixels are drawn multiple times.
All three functions use these GC components: function,
plane-mask, line-width, line-style, cap-style, fill-
style, subwindow-mode, clip-x-origin, clip-y-origin,
and clip-mask. The XDrawLines function also uses the
join-style GC component. All three functions also use
these GC mode-dependent components: foreground,
background, tile, stipple, tile-stipple-x-origin,
tile-stipple-y-origin, dash-offset, and dash-list.
XDrawLine, XDrawLines, and XDrawSegments can generate
BadDrawable, BadGC, and BadMatch errors. XDrawLines
can also generate a BadValue error.
DIAGNOSTICS
BadDrawable
A value for a Drawable argument does not name
a defined Window or Pixmap.
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XDrawLine(3X) XDrawLine(3X)
BadGC A value for a GContext argument does not name
a defined GContext.
BadMatch An InputOnly window is used as a Drawable.
BadMatch Some argument or pair of arguments has the
correct type and range but fails to match in
some other way required by the request.
BadValue Some numeric value falls outside the range of
values accepted by the request. Unless a
specific range is specified for an argument,
the full range defined by the argument's type
is accepted. Any argument defined as a set
of alternatives can generate this error.
SEE ALSO
XDrawArc(3X11), XDrawPoint(3X11), XDrawRectangle(3X11)
Xlib Programming Manual
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