Manpages - XDrawRectangle.3

XDrawRectangle, XDrawRectangles, XRectangle - draw rectangles and rectangles structure

int XDrawRectangle ( Display */display/ , Drawable d , GC gc , int x , int y , unsigned int width , unsigned int height );

int XDrawRectangles ( Display */display/ , Drawable d , GC gc , XRectangle rectangles [ ] , int nrectangles );

1. Specifies the drawable.
2. Specifies the connection to the X server.
3. Specifies the GC.
4. Specifies the number of rectangles in the array.
5. Specifies an array of rectangles.
6. 
   
7. Specify the width and height, which specify the dimensions of the rectangle.
8. 
   
9. Specify the x and y coordinates, which specify the upper-left corner of the rectangle.

The XDrawRectangle and XDrawRectangles 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 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 and XDrawRectangles 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.

BadDrawable

A value for a Drawable argument does not name a defined Window or Pixmap.

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.

XDrawArc(3), XDrawLine(3), XDrawPoint(3)
Xlib - C Language X Interface