Golang Image.XDraw方法代碼示例

// clearCanvas erases all your pencil marks.
func clearCanvas(canvas *xgraphics.Image, win *xwindow.Window) {
	log.Println("Clearing canvas...")
	canvas.For(func(x, y int) xgraphics.BGRA {
		return bg
	})

	canvas.XDraw()
	canvas.XPaint(win.Id)
}

// This is a slightly modified version of xgraphics.XShowExtra that does
// not set any resize constraints on the window (so that it can go
// fullscreen).
func showImage(im *xgraphics.Image, name string, quit bool) *xwindow.Window {
	if len(name) == 0 {
		name = "xgbutil Image Window"
	}
	w, h := im.Rect.Dx(), im.Rect.Dy()

	win, err := xwindow.Generate(im.X)
	if err != nil {
		xgbutil.Logger.Printf("Could not generate new window id: %s", err)
		return nil
	}

	// Create a very simple window with dimensions equal to the image.
	win.Create(im.X.RootWin(), 0, 0, w, h, 0)

	// Make this window close gracefully.
	win.WMGracefulClose(func(w *xwindow.Window) {
		xevent.Detach(w.X, w.Id)
		keybind.Detach(w.X, w.Id)
		mousebind.Detach(w.X, w.Id)
		w.Destroy()

		if quit {
			xevent.Quit(w.X)
		}
	})

	// Set WM_STATE so it is interpreted as a top-level window.
	err = icccm.WmStateSet(im.X, win.Id, &icccm.WmState{
		State: icccm.StateNormal,
	})
	if err != nil { // not a fatal error
		xgbutil.Logger.Printf("Could not set WM_STATE: %s", err)
	}

	// Set _NET_WM_NAME so it looks nice.
	err = ewmh.WmNameSet(im.X, win.Id, name)
	if err != nil { // not a fatal error
		xgbutil.Logger.Printf("Could not set _NET_WM_NAME: %s", err)
	}

	// Paint our image before mapping.
	im.XSurfaceSet(win.Id)
	im.XDraw()
	im.XPaint(win.Id)

	// Now we can map, since we've set all our properties.
	// (The initial map is when the window manager starts managing.)
	win.Map()

	return win
}

// SetRoot sets the given background as the root window background.
func SetRoot(X *xgbutil.XUtil, bg *xgraphics.Image) error {
	root := X.RootWin()
	if err := bg.XSurfaceSet(root); err != nil {
		return err
	}
	bg.XDraw()
	bg.XPaint(root)
	// FIXME: This doesn't set the pixmap persistently. As soon as the program
	// exits, the pixmap is destroyed. Find a way to make it persistent.
	xprop.ChangeProp32(X, root, "_XROOTPMAP_ID", "PIXMAP", uint(bg.Pixmap))
	xprop.ChangeProp32(X, root, "ESETROOT_PMAP_ID", "PIXMAP", uint(bg.Pixmap))
	return nil
}

func (p *piece) Create(act, inact *xgraphics.Image) {
	if act != nil {
		if p.active > 0 {
			xgraphics.FreePixmap(p.X, p.active)
		}
		act.CreatePixmap()
		act.XDraw()

		p.active = act.Pixmap
	}
	if inact != nil {
		if p.inactive > 0 {
			xgraphics.FreePixmap(p.X, p.inactive)
		}
		inact.CreatePixmap()
		inact.XDraw()

		p.inactive = inact.Pixmap
	}
}

// SetImageToBg sets the given image into the background at the proper location
// for the named output to display.
func SetImageToBg(X *xgbutil.XUtil,
	bg *xgraphics.Image,
	img image.Image,
	name string) error {

	output, err := util.GetOutputByName(X, name)
	if err != nil {
		return err
	}
	geom, err := util.OutputRect(X, output)
	if err != nil {
		return err
	}
	if err = bg.CreatePixmap(); err != nil {
		return err
	}
	bg.XDraw()
	draw.Draw(bg, geom, img, img.Bounds().Min, draw.Src)
	return nil
}