Golang XUtil.Screen方法代碼示例

// checkCompatibility reads info in the X setup info struct and emits
// messages to stderr if they don't correspond to values that xgraphics
// supports.
// The idea is that in the future, we'll support more values.
// The real reason for checkCompatibility is to make debugging easier. Without
// it, if the values weren't what we'd expect, we'd see garbled images in the
// best case, and probably BadLength errors in the worst case.
func checkCompatibility(X *xgbutil.XUtil) {
	s := X.Setup()
	scrn := X.Screen()
	failed := false

	if s.ImageByteOrder != xproto.ImageOrderLSBFirst {
		log.Printf("Your X server uses MSB image byte order. Unfortunately, " +
			"xgraphics currently requires LSB image byte order. You may see " +
			"weird things. Please report this.")
		failed = true
	}
	if s.BitmapFormatBitOrder != xproto.ImageOrderLSBFirst {
		log.Printf("Your X server uses MSB bitmap bit order. Unfortunately, " +
			"xgraphics currently requires LSB bitmap bit order. If you " +
			"aren't using X bitmaps, you should be able to proceed normally. " +
			"Please report this.")
		failed = true
	}
	if s.BitmapFormatScanlineUnit != 32 {
		log.Printf("xgraphics expects that the scanline unit is set to 32, "+
			"but your X server has it set to '%d'. "+
			"Namely, xgraphics hasn't been tested on other values. Things "+
			"may still work. Particularly, if you aren't using X bitmaps, "+
			"you should be completely unaffected. Please report this.",
			s.BitmapFormatScanlineUnit)
		failed = true
	}
	if scrn.RootDepth != 24 {
		log.Printf("xgraphics expects that the root window has a depth of 24, "+
			"but yours has depth '%d'. Its possible things will still work "+
			"if your value is 32, but will be unlikely to work with values "+
			"less than 24. Please report this.", scrn.RootDepth)
		failed = true
	}

	// Look for the default format for pixmaps and make sure bits per pixel
	// is 32.
	format := xgraphics.GetFormat(X, scrn.RootDepth)
	if format.BitsPerPixel != 32 {
		log.Printf("xgraphics expects that the bits per pixel for the root "+
			"window depth is 32. On your system, the root depth is %d and "+
			"the bits per pixel is %d. Things will most certainly not work. "+
			"Please report this.",
			scrn.RootDepth, format.BitsPerPixel)
		failed = true
	}

	// Give instructions on reporting the issue.
	if failed {
		log.Printf("Please report the aforementioned error message(s) at " +
			"https://github.com/BurntSushi/xgbutil. Please also include the " +
			"entire output of the `xdpyinfo` command in your report. Thanks!")
	} else {
		log.Printf("No compatibility issues detected.")
	}
}

func getVisualDepth(X *xgbutil.XUtil, vid xproto.Visualid) byte {
	for _, dinfo := range X.Screen().AllowedDepths {
		for _, vis := range dinfo.Visuals {
			if vis.VisualId == vid {
				return dinfo.Depth
			}
		}
	}
	panic(fmt.Sprintf("Could not find depth for visual %d", vid))
}

func newParent(X *xgbutil.XUtil, cid xproto.Window) (*Parent, error) {
	parent, err := xwindow.Generate(X)
	if err != nil {
		logger.Error.Printf("Could not create a parent window for client "+
			"with id '%d' because: %s", cid, err)
		logger.Error.Fatalf("In a state where no new windows can be created. " +
			"Unfortunately, we must exit.")
	}

	// clientAttrs, err := xproto.GetWindowAttributes(X.Conn(), cid).Reply()
	// if err != nil {
	// return nil, fmt.Errorf("Could not get window attributes: %s", err)
	// }

	// visual := clientAttrs.Visual
	// vdepth := getVisualDepth(X, visual)
	visual := X.Screen().RootVisual
	vdepth := X.Screen().RootDepth
	// logger.Debug.Printf("Visualid: %x, Depth: %d", visual, vdepth)
	err = xproto.CreateWindowChecked(X.Conn(),
		vdepth, parent.Id, X.RootWin(),
		0, 0, 1, 1, 0, xproto.WindowClassInputOutput, visual,
		xproto.CwEventMask,
		[]uint32{
			xproto.EventMaskSubstructureRedirect |
				xproto.EventMaskButtonPress |
				xproto.EventMaskButtonRelease |
				xproto.EventMaskFocusChange,
		}).Check()
	if err != nil {
		return nil, fmt.Errorf("Could not create window: %s", err)
	}

	err = xproto.ReparentWindowChecked(X.Conn(),
		cid, parent.Id, 0, 0).Check()
	if err != nil {
		return nil, fmt.Errorf("Could not reparent window: %s", err)
	}

	return &Parent{
		Window:      parent,
		MoveState:   &MoveState{},
		ResizeState: &ResizeState{},
		isMapped:    false,
	}, nil
}

// getVisualInfo searches SetupInfo for a VisualInfo value matching
// the depth provided.
// XXX: This isn't used (yet).
func getVisualInfo(X *xgbutil.XUtil, depth byte,
	visualid xproto.Visualid) *xproto.VisualInfo {

	for _, depthInfo := range X.Screen().AllowedDepths {
		fmt.Printf("%#v\n", depthInfo)
		// fmt.Printf("%#v\n", depthInfo.Visuals)
		fmt.Println("------------")
		if depthInfo.Depth == depth {
			for _, visual := range depthInfo.Visuals {
				if visual.VisualId == visualid {
					return &visual
				}
			}
		}
	}
	return nil
}