Query: xdrawlines
OS: hpux
Section: 3
Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar
XDrawLines() XDrawLines()
Name
XDrawLines - draw multiple connected lines.
Synopsis
XDrawLines(display, drawable, gc, points, npoints, mode)
Display *display;
Drawable drawable;
GC gc;
XPoint *points;
int npoints;
int mode;
Arguments
display Specifies a connection to an X server; returned from XOpenDisplay().
drawable Specifies the drawable.
gc Specifies the graphics context.
points Specifies a pointer to an array of points.
npoints Specifies the number of points in the array.
mode Specifies the coordinate mode. Pass either CoordModeOrigin or CoordModePrevious.
Description
XDrawLines() draws a series of lines joined end-to-end.
It draws lines connecting each point in the list (points array) to the next point in the list. The lines are drawn in the order listed in
the points array. For any given line, no pixel is drawn more than once. If thin (zero line width) lines intersect, pixels will be drawn
multiple times. If the first and last points coincide, the first and last lines will join correctly. If wide lines intersect, the inter-
secting pixels are drawn only once, as though the entire multiline request were a single filled shape.
There is a limit to the number of lines that can be drawn in a single call, which varies according to the server. To determine how many
lines you can draw in a single call, find out your server's maximum request size using XMaxRequestSize(). Subtract three and divide by
two, and this is the maximum number of lines you can draw in a single XDrawLines() call.
The mode argument may have two values:
o CoordModeOrigin indicates that all points are relative to the drawable's origin.
o CoordModePrevious indicates that all points after the first are relative to the previous point. (The first point is always relative to
the drawable's origin.)
XDrawLines() uses the following components of the specified graphics context to draw multiple connected lines in the specified drawable:
function, plane_mask, line_width, line_style, cap_style, join_style, fill_style, subwindow_mode, clip_x_origin, clip_y_ origin, and
clip_mask. This function also uses these graphics context mode-dependent components: foreground, background, tile, stipple, ts_x_origin,
ts_y_origin, dash_offset, and dashes.
For more information, see Volume One, Chapter 6, Drawing Graphics and Text, and Chapter 5, The Graphics Context.
Structures
typedef struct {
short x, y;
} XPoint;
Errors
BadDrawable
Specified drawable is invalid.
BadGC Specified GC is invalid, or does not match the depth of drawable.
BadMatch Specified drawable is an InputOnly window.
BadValue Invalid coordinate_mode.
See Also
XClearArea(), XClearWindow(), XCopyArea(), XCopyPlane(), XDraw, XDrawArc(), XDrawArcs(), XDrawFilled(), XDrawLine(), XDrawPoint(), XDraw-
Points(), XDrawRectangle(), XDrawRectangles(), XDrawSegments(), XFillArc(), XFillArcs(), XFillPolygon(), XFillRectangle(), XFillRectan-
gles().
Xlib - Drawing Primitives XDrawLines()