package main import ( "encoding/binary" "github.com/BurntSushi/xgb" "github.com/BurntSushi/xgb/render" "github.com/BurntSushi/xgb/xproto" "log" "os" "time" "image" _ "image/gif" _ "image/jpeg" _ "image/png" ) func F64ToFixed(f float64) render.Fixed { return render.Fixed(f * 65536) } func FixedToF64(f render.Fixed) float64 { return float64(f) / 65536 } func main() { /* pf, err := os.Create("pprof.out") if err != nil { log.Fatal(err) } pprof.StartCPUProfile(pf) defer pprof.StopCPUProfile() */ // Load a picture from the command line. f, err := os.Open(os.Args[1]) if err != nil { log.Fatalln(err) } defer f.Close() img, name, err := image.Decode(f) if err != nil { log.Fatalln(err) } log.Println("image type is", name) // Miscellaneous X11 initialization. X, err := xgb.NewConn() if err != nil { log.Fatalln(err) } if err := render.Init(X); err != nil { log.Fatalln(err) } setup := xproto.Setup(X) screen := setup.DefaultScreen(X) visual, depth := screen.RootVisual, screen.RootDepth // TODO: We should check that we find it, though we don't /need/ alpha here, // it's just a minor improvement--affects the backpixel value. for _, i := range screen.AllowedDepths { for _, v := range i.Visuals { // TODO: Could/should check other parameters. if i.Depth == 32 && v.Class == xproto.VisualClassTrueColor { visual, depth = v.VisualId, i.Depth break } } } mid, err := xproto.NewColormapId(X) if err != nil { log.Fatalln(err) } _ = xproto.CreateColormap( X, xproto.ColormapAllocNone, mid, screen.Root, visual) wid, err := xproto.NewWindowId(X) if err != nil { log.Fatalln(err) } // Border pixel and colormap are required when depth differs from parent. _ = xproto.CreateWindow(X, depth, wid, screen.Root, 0, 0, 500, 500, 0, xproto.WindowClassInputOutput, visual, xproto.CwBackPixel|xproto.CwBorderPixel|xproto.CwEventMask| xproto.CwColormap, []uint32{0x80808080, 0, xproto.EventMaskStructureNotify | xproto.EventMaskExposure, uint32(mid)}) title := []byte("Image") _ = xproto.ChangeProperty(X, xproto.PropModeReplace, wid, xproto.AtomWmName, xproto.AtomString, 8, uint32(len(title)), title) _ = xproto.MapWindow(X, wid) pformats, err := render.QueryPictFormats(X).Reply() if err != nil { log.Fatalln(err) } // Similar to XRenderFindVisualFormat. // The DefaultScreen is almost certain to be zero. var pformat render.Pictformat for _, pd := range pformats.Screens[X.DefaultScreen].Depths { // This check seems to be slightly extraneous. if pd.Depth != depth { continue } for _, pv := range pd.Visuals { if pv.Visual == visual { pformat = pv.Format } } } // Wrap the window's surface in a picture. pid, err := render.NewPictureId(X) if err != nil { log.Fatalln(err) } render.CreatePicture(X, pid, xproto.Drawable(wid), pformat, 0, []uint32{}) // setup.BitmapFormatScanline{Pad,Unit} and setup.BitmapFormatBitOrder // don't interest us here since we're only using Z format pixmaps. for _, pf := range setup.PixmapFormats { if pf.Depth == 32 { if pf.BitsPerPixel != 32 || pf.ScanlinePad != 32 { log.Fatalln("unsuported X server") } } } pixid, err := xproto.NewPixmapId(X) if err != nil { log.Fatalln(err) } _ = xproto.CreatePixmap(X, 32, pixid, xproto.Drawable(screen.Root), uint16(img.Bounds().Dx()), uint16(img.Bounds().Dy())) var bgraFormat render.Pictformat wanted := render.Directformat{ RedShift: 16, RedMask: 0xff, GreenShift: 8, GreenMask: 0xff, BlueShift: 0, BlueMask: 0xff, AlphaShift: 24, AlphaMask: 0xff, } for _, pf := range pformats.Formats { if pf.Depth == 32 && pf.Direct == wanted { bgraFormat = pf.Id break } } if bgraFormat == 0 { log.Fatalln("ARGB format not found") } // We could also look for the inverse pictformat. var encoding binary.ByteOrder if setup.ImageByteOrder == xproto.ImageOrderMSBFirst { encoding = binary.BigEndian } else { encoding = binary.LittleEndian } pixpicid, err := render.NewPictureId(X) if err != nil { log.Fatalln(err) } render.CreatePicture(X, pixpicid, xproto.Drawable(pixid), bgraFormat, 0, []uint32{}) // Do we really need this? :/ cid, err := xproto.NewGcontextId(X) if err != nil { log.Fatalln(err) } _ = xproto.CreateGC(X, cid, xproto.Drawable(pixid), xproto.GcGraphicsExposures, []uint32{0}) // Load data into the pixmap. Also see xgbutil/xgraphics/xsurface.go. // We're being lazy and resolve the 1<<16 limit of requests by sending // a row at a time. The encoding is also done inefficiently. bounds := img.Bounds() Lstart := time.Now() row := make([]byte, bounds.Dx()*4) for y := bounds.Min.Y; y < bounds.Max.Y; y++ { for x := bounds.Min.X; x < bounds.Max.X; x++ { r, g, b, a := img.At(x, y).RGBA() encoding.PutUint32(row[x*4:], (a>>8)<<24|(r>>8)<<16|(g>>8)<<8|(b>>8)) } _ = xproto.PutImage(X, xproto.ImageFormatZPixmap, xproto.Drawable(pixid), cid, uint16(bounds.Dx()), 1, 0, int16(y), 0, 32, row) } log.Println("uploading took", time.Now().Sub(Lstart)) // TODO: SHM, for an example see https://github.com/BurntSushi/xgb/issues/28 var scale float64 = 1 for { ev, xerr := X.WaitForEvent() if xerr != nil { log.Printf("Error: %s\n", xerr) return } if ev == nil { return } log.Printf("Event: %s\n", ev) switch e := ev.(type) { case xproto.UnmapNotifyEvent: return case xproto.ConfigureNotifyEvent: w, h := e.Width, e.Height scaleX := float64(bounds.Dx()) / float64(w) scaleY := float64(bounds.Dy()) / float64(h) if scaleX < scaleY { scale = scaleY } else { scale = scaleX } _ = render.SetPictureTransform(X, pixpicid, render.Transform{ F64ToFixed(scale), F64ToFixed(0), F64ToFixed(0), F64ToFixed(0), F64ToFixed(scale), F64ToFixed(0), F64ToFixed(0), F64ToFixed(0), F64ToFixed(1), }) _ = render.SetPictureFilter(X, pixpicid, 8, "bilinear", nil) case xproto.ExposeEvent: _ = render.Composite(X, render.PictOpSrc, pixpicid, render.PictureNone, pid, 0, 0, 0, 0, 0 /* dst-x */, 0, /* dst-y */ uint16(float64(img.Bounds().Dx())/scale), uint16(float64(img.Bounds().Dy())/scale)) } } }