Data commit

Task/Joystick-position/Go/joystick-position.go

@@ -0,0 +1,103 @@
+package main
+
+import (
+    "fmt"
+    "github.com/nsf/termbox-go"
+    "github.com/simulatedsimian/joystick"
+    "log"
+    "os"
+    "strconv"
+    "time"
+)
+
+func printAt(x, y int, s string) {
+    for _, r := range s {
+        termbox.SetCell(x, y, r, termbox.ColorDefault, termbox.ColorDefault)
+        x++
+    }
+}
+
+func readJoystick(js joystick.Joystick, hidden bool) {
+    jinfo, err := js.Read()
+    check(err)
+
+    w, h := termbox.Size()
+    tbcd := termbox.ColorDefault
+    termbox.Clear(tbcd, tbcd)
+    printAt(1, h-1, "q - quit")
+    if hidden {
+        printAt(11, h-1, "s - show buttons:")
+    } else {
+        bs := ""
+        printAt(11, h-1, "h - hide buttons:")
+        for button := 0; button < js.ButtonCount(); button++ {
+            if jinfo.Buttons&(1<<uint32(button)) != 0 {
+                // Buttons assumed to be numbered from 1, not 0.
+                bs += fmt.Sprintf(" %X", button+1)
+            }
+        }
+        printAt(28, h-1, bs)
+    }
+
+    // Map axis values in range -32767 to +32768 to termbox co-ordinates.
+    x := int(float64((jinfo.AxisData[0]+32767)*(w-1)) / 65535)
+    y := int(float64((jinfo.AxisData[1]+32767)*(h-2)) / 65535)
+    printAt(x, y, "+") // display crosshair
+    termbox.Flush()
+}
+
+func check(err error) {
+    if err != nil {
+        log.Fatal(err)
+    }
+}
+
+func main() {
+    // Under Linux the id is used to construct the joystick device name.
+    // For example: id 0 will open device: "/dev/input/js0"
+    // Under Windows the id is the actual numeric id of the joystick.
+    jsid := 0
+    // Optionally pass joystick id to be used as a command line argument.
+    if len(os.Args) > 1 {
+        i, err := strconv.Atoi(os.Args[1])
+        check(err)
+        jsid = i
+    }
+
+    js, jserr := joystick.Open(jsid)
+    check(jserr)
+
+    err := termbox.Init()
+    check(err)
+    defer termbox.Close()
+
+    eventQueue := make(chan termbox.Event)
+    go func() {
+        for {
+            eventQueue <- termbox.PollEvent()
+        }
+    }()
+
+    ticker := time.NewTicker(time.Millisecond * 40)
+    hidden := false // Controls whether button display hidden or not.
+
+    for doQuit := false; !doQuit; {
+        select {
+        case ev := <-eventQueue:
+            if ev.Type == termbox.EventKey {
+                if ev.Ch == 'q' {
+                    doQuit = true
+                } else if ev.Ch == 'h' {
+                    hidden = true
+                } else if ev.Ch == 's' {
+                    hidden = false
+                }
+            }
+            if ev.Type == termbox.EventResize {
+                termbox.Flush()
+            }
+        case <-ticker.C:
+            readJoystick(js, hidden)
+        }
+    }
+}