func NewWindow(width, height int) (wde.Window, error) {
var err error
w := new(Window)
w.width, w.height = width, height
w.xu, err = xgbutil.NewConn()
if err != nil {
return nil, err
}
w.conn = w.xu.Conn()
screen := w.xu.Screen()
w.win, err = xwindow.Generate(w.xu)
if err != nil {
return nil, err
}
err = w.win.CreateChecked(screen.Root, 600, 500, width, height, 0)
if err != nil {
return nil, err
}
w.win.Listen(AllEventsMask)
err = icccm.WmProtocolsSet(w.xu, w.win.Id, []string{"WM_DELETE_WINDOW"})
if err != nil {
fmt.Println(err)
err = nil
}
w.bufferLck = &sync.Mutex{}
w.buffer = xgraphics.New(w.xu, image.Rect(0, 0, width, height))
w.buffer.XSurfaceSet(w.win.Id)
keyMap, modMap := keybind.MapsGet(w.xu)
keybind.KeyMapSet(w.xu, keyMap)
keybind.ModMapSet(w.xu, modMap)
w.events = make(chan interface{})
w.SetIcon(Gordon)
w.SetIconName("Go")
go w.handleEvents()
return w, nil
}
func main() {
X, err := xgbutil.NewConn()
fatal(err)
// Whenever the mousebind package is used, you must call Initialize.
// Similarly for the keybind package.
keybind.Initialize(X)
mousebind.Initialize(X)
// Easter egg! Use a right click to draw a gopher.
gopherPng, _, err := image.Decode(bytes.NewBuffer(gopher.GopherPng()))
fatal(err)
// Now scale it to a reasonable size.
gopher := xgraphics.Scale(gopherPng, gopherWidth, gopherHeight)
// Create a new xgraphics.Image. It automatically creates an X pixmap for
// you, and handles drawing to windows in the XDraw, XPaint and
// XSurfaceSet functions.
// N.B. An error is possible since X pixmap allocation can fail.
canvas := xgraphics.New(X, image.Rect(0, 0, width, height))
// Color in the background color.
canvas.For(func(x, y int) xgraphics.BGRA {
return bg
})
// Use the convenience function XShowExtra to create and map the
// canvas window.
// XShowExtra will also set the surface window of canvas for us.
// We also use XShowExtra to set the name of the window and to quit the
// main event loop when the window is closed.
win := canvas.XShowExtra("Pointer painting", true)
// Listen for pointer motion events and key press events.
win.Listen(xproto.EventMaskButtonPress | xproto.EventMaskButtonRelease |
xproto.EventMaskKeyPress)
// The mousebind drag function runs three callbacks: one when the drag is
// first started, another at each "step" in the drag, and a final one when
// the drag is done.
// The button sequence (in this case '1') is pressed, the first callback
// is executed. If the first return value is true, the drag continues
// and a pointer grab is initiated with the cursor id specified in the
// second return value (use 0 to keep the cursor unchanged).
// If it's false, the drag stops.
// Note that Drag will automatically compress MotionNotify events.
mousebind.Drag(X, win.Id, win.Id, "1", false,
func(X *xgbutil.XUtil, rx, ry, ex, ey int) (bool, xproto.Cursor) {
drawPencil(canvas, win, ex, ey)
return true, 0
},
func(X *xgbutil.XUtil, rx, ry, ex, ey int) {
drawPencil(canvas, win, ex, ey)
},
func(X *xgbutil.XUtil, rx, ry, ex, ey int) {})
mousebind.Drag(X, win.Id, win.Id, "3", false,
func(X *xgbutil.XUtil, rx, ry, ex, ey int) (bool, xproto.Cursor) {
drawGopher(canvas, gopher, win, ex, ey)
return true, 0
},
func(X *xgbutil.XUtil, rx, ry, ex, ey int) {
drawGopher(canvas, gopher, win, ex, ey)
},
func(X *xgbutil.XUtil, rx, ry, ex, ey int) {})
// Bind to the clear key specified, and just redraw the bg color.
keybind.KeyPressFun(
func(X *xgbutil.XUtil, ev xevent.KeyPressEvent) {
clearCanvas(canvas, win)
}).Connect(X, win.Id, clearKey, false)
// Bind a callback to each key specified in the 'pencils' color map.
// The response is to simply switch the pencil color.
for key, clr := range pencils {
c := clr
keybind.KeyPressFun(
func(X *xgbutil.XUtil, ev xevent.KeyPressEvent) {
log.Printf("Changing pencil color to: %#v", c)
pencil = c
}).Connect(X, win.Id, key, false)
}
// Output some basic directions.
fmt.Println("Use the left or right buttons on your mouse to paint " +
"squares and gophers.")
fmt.Println("Pressing numbers 1, 2, 3, 4, 5 or 6 will switch your pencil " +
"color.")
fmt.Println("Pressing 'c' will clear the canvas.")
xevent.Main(X)
}
func (w *Window) handleEvents() {
const noX int32 = -1
var lastX, lastY int32 = noX, 0
var button wde.Button
downKeys := map[string]bool{}
for {
e, err := w.conn.WaitForEvent()
if err != nil {
fmt.Println("[go.wde X error] ", err)
continue
}
switch e := e.(type) {
case xproto.ButtonPressEvent:
button = button | buttonForDetail(e.Detail)
var bpe wde.MouseDownEvent
bpe.Which = buttonForDetail(e.Detail)
bpe.Where.X = int(e.EventX)
bpe.Where.Y = int(e.EventY)
lastX = int32(e.EventX)
lastY = int32(e.EventY)
w.events <- bpe
case xproto.ButtonReleaseEvent:
button = button & ^buttonForDetail(e.Detail)
var bue wde.MouseUpEvent
bue.Which = buttonForDetail(e.Detail)
bue.Where.X = int(e.EventX)
bue.Where.Y = int(e.EventY)
lastX = int32(e.EventX)
lastY = int32(e.EventY)
w.events <- bue
case xproto.LeaveNotifyEvent:
var wee wde.MouseExitedEvent
wee.Where.X = int(e.EventX)
wee.Where.Y = int(e.EventY)
if lastX != noX {
wee.From.X = int(lastX)
wee.From.Y = int(lastY)
} else {
wee.From.X = wee.Where.X
wee.From.Y = wee.Where.Y
}
lastX = int32(e.EventX)
lastY = int32(e.EventY)
w.events <- wee
case xproto.EnterNotifyEvent:
var wee wde.MouseEnteredEvent
wee.Where.X = int(e.EventX)
wee.Where.Y = int(e.EventY)
if lastX != noX {
wee.From.X = int(lastX)
wee.From.Y = int(lastY)
} else {
wee.From.X = wee.Where.X
wee.From.Y = wee.Where.Y
}
lastX = int32(e.EventX)
lastY = int32(e.EventY)
w.events <- wee
case xproto.MotionNotifyEvent:
var mme wde.MouseMovedEvent
mme.Where.X = int(e.EventX)
mme.Where.Y = int(e.EventY)
if lastX != noX {
mme.From.X = int(lastX)
mme.From.Y = int(lastY)
} else {
mme.From.X = mme.Where.X
mme.From.Y = mme.Where.Y
}
lastX = int32(e.EventX)
lastY = int32(e.EventY)
if button == 0 {
w.events <- mme
} else {
var mde wde.MouseDraggedEvent
mde.MouseMovedEvent = mme
mde.Which = button
w.events <- mde
}
case xproto.KeyPressEvent:
var ke wde.KeyEvent
code := keybind.LookupString(w.xu, e.State, e.Detail)
ke.Key = keyForCode(code)
w.events <- wde.KeyDownEvent(ke)
downKeys[ke.Key] = true
kpe := wde.KeyTypedEvent{
KeyEvent: ke,
Glyph: letterForCode(code),
Chord: wde.ConstructChord(downKeys),
}
w.events <- kpe
case xproto.KeyReleaseEvent:
var ke wde.KeyUpEvent
ke.Key = keyForCode(keybind.LookupString(w.xu, e.State, e.Detail))
delete(downKeys, ke.Key)
w.events <- ke
case xproto.ConfigureNotifyEvent:
var re wde.ResizeEvent
re.Width = int(e.Width)
re.Height = int(e.Height)
if re.Width != w.width || re.Height != w.height {
w.width, w.height = re.Width, re.Height
w.bufferLck.Lock()
w.buffer.Destroy()
w.buffer = xgraphics.New(w.xu, image.Rect(0, 0, re.Width, re.Height))
w.bufferLck.Unlock()
w.events <- re
}
case xproto.ClientMessageEvent:
if icccm.IsDeleteProtocol(w.xu, xevent.ClientMessageEvent{&e}) {
w.events <- wde.CloseEvent{}
}
case xproto.DestroyNotifyEvent:
case xproto.ReparentNotifyEvent:
case xproto.MapNotifyEvent:
case xproto.UnmapNotifyEvent:
case xproto.PropertyNotifyEvent:
default:
fmt.Printf("unhandled event: type %T\n%+v\n", e, e)
}
}
close(w.events)
}