XDrawRectangle(), XDrawRectangles(), XRectangle() - draw rectangles and rectangles structure
XDrawRectangle (Display *display, Drawable d, GC gc,
int x, int y, unsigned int width,
unsigned int height)
XDrawRectangles (Display *display, Drawable d, GC gc,
XRectangle rectangles[ ], int nrectangles)
The XDrawRectangle(3) and XDrawRectangles(3) functions draw the outlines of the specified rectangle or rectangles as if a five-point PolyLine protocol request were specified for each rectangle:
[x,y] [x+width,y] [x+width,y+height] [x,y+height] [x,y]
For the specified rectangle or rectangles, these functions do not draw a pixel more than once. XDrawRectangles(3) draws the rectangles in the order listed in the array. If rectangles intersect, the intersecting pixels are drawn multiple times.
Both functions use these GC components: function, plane-mask, line-width, line-style, cap-style, join-style, fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask. They also use these GC mode-dependent components: foreground, background, tile, stipple, tile-stipple-x-origin, tile-stipple-y-origin, dash-offset, and dash-list.
XDrawRectangle(3) and XDrawRectangles(3) can generate BadDrawable, BadGC, and BadMatch errors.
The XRectangle structure contains:
typedef struct {
short x, y;
unsigned short width, height;
} XRectangle;
All x and y members are signed integers. The width and height members are 16-bit unsigned integers. You should be careful not to generate coordinates and sizes out of the 16-bit ranges, because the protocol only has 16-bit fields for these values.
Xlib