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 main() {
// Connect to the X server using the DISPLAY environment variable.
X, err := xgbutil.NewConn()
if err != nil {
log.Fatal(err)
}
// Nice names for the modifier keys (same ones used by xmodmap).
// This slice corresponds to the keybind.Modifiers slice (except for
// the last 'Any' modifier element).
nice := []string{
"shift", "lock", "control", "mod1", "mod2", "mod3", "mod4", "mod5",
}
// Whenever one uses the keybind package, Initialize should always be
// called first. In this case, it initializes the key and modifier maps.
keybind.Initialize(X)
// Get the current modifier map.
// The map is actually a table, where rows correspond to modifiers, and
// columns correspond to the keys that activate that modifier.
modMap := keybind.ModMapGet(X)
// The number of keycodes allowed per modifier (i.e., the number of
// columns in the modifier map).
kPerMod := int(modMap.KeycodesPerModifier)
// Get the number of allowable keysyms per keycode.
// This is used to search for a valid keysym for a particular keycode.
symsPerKc := int(keybind.KeyMapGet(X).KeysymsPerKeycode)
// Imitate everything...
fmt.Printf("xmodmap: up to %d keys per modifier, "+
"(keycodes in parentheses):\n\n", kPerMod)
// Iterate through all keyboard modifiers defined in xgb/xproto
// except the 'Any' modifier (which is last).
for mmi := range keybind.Modifiers[:len(keybind.Modifiers)-1] {
niceName := nice[mmi]
keys := make([]string, 0, kPerMod)
// row is the row for the 'mmi' modifier in the modifier mapping table.
row := mmi * kPerMod
// Iterate over each keycode in the modifier map for this modifier.
for _, kc := range modMap.Keycodes[row : row+kPerMod] {
// If this entry doesn't have a keycode (i.e., it's zero), we
// have to skip it.
if kc == 0 {
continue
}
// Look for the first valid keysym in the keyboard map corresponding
// to this keycode. If one can't be found, output "BadKey."
var ksym xproto.Keysym = 0
for column := 0; column < symsPerKc; column++ {
ksym = keybind.KeysymGet(X, kc, byte(column))
if ksym != 0 {
break
}
}
if ksym == 0 {
keys = append(keys, fmt.Sprintf("BadKey (0x%x)", kc))
} else {
keys = append(keys,
fmt.Sprintf("%s (0x%x)", keybind.KeysymToStr(ksym), kc))
}
}
fmt.Printf("%-12s%s\n", niceName, strings.Join(keys, ", "))
}
fmt.Println("")
}