examples: add joystick-input example

Signed-off-by: Lilis Iskandar <lilis@veand.co>

examples/joystick-input/joystick-input.go

@@ -0,0 +1,94 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+var joysticks [16]*sdl.Joystick
+
+func run() (err error) {
+	var window *sdl.Window
+
+	if err = sdl.Init(sdl.INIT_EVERYTHING); err != nil {
+		return
+	}
+	defer sdl.Quit()
+
+	window, err = sdl.CreateWindow("Input", sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED, 800, 600, sdl.WINDOW_SHOWN)
+	if err != nil {
+		return
+	}
+	defer window.Destroy()
+
+	sdl.JoystickEventState(sdl.ENABLE)
+
+	running := true
+	for running {
+		for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
+			switch t := event.(type) {
+			case *sdl.QuitEvent:
+				running = false
+			case *sdl.JoyAxisEvent:
+				fmt.Printf("[%d ms] JoyAxis\ttype:%d\twhich:%c\taxis:%d\tvalue:%d\n",
+					t.Timestamp, t.Type, t.Which, t.Axis, t.Value)
+			case *sdl.JoyBallEvent:
+				fmt.Println("Joystick", t.Which, "trackball moved by", t.XRel, t.YRel)
+			case *sdl.JoyButtonEvent:
+				if t.Type == sdl.PRESSED {
+					fmt.Println("Joystick", t.Which, "button", t.Button, "pressed")
+				} else {
+					fmt.Println("Joystick", t.Which, "button", t.Button, "released")
+				}
+			case *sdl.JoyHatEvent:
+				position := ""
+
+				switch t.Value {
+				case sdl.HAT_LEFTUP:
+					position = "top-left"
+				case sdl.HAT_UP:
+					position = "top"
+				case sdl.HAT_RIGHTUP:
+					position = "top-right"
+				case sdl.HAT_RIGHT:
+					position = "right"
+				case sdl.HAT_RIGHTDOWN:
+					position = "bottom-right"
+				case sdl.HAT_DOWN:
+					position = "bottom"
+				case sdl.HAT_LEFTDOWN:
+					position = "bottom-left"
+				case sdl.HAT_LEFT:
+					position = "left"
+				case sdl.HAT_CENTERED:
+					position = "center"
+				}
+
+				fmt.Println("Joystick", t.Which, "hat", t.Hat, "moved to", position, "position")
+			case *sdl.JoyDeviceAddedEvent:
+				// Open joystick for use
+				joysticks[int(t.Which)] = sdl.JoystickOpen(t.Which)
+				if joysticks[int(t.Which)] != nil {
+					fmt.Println("Joystick", t.Which, "connected")
+				}
+			case *sdl.JoyDeviceRemovedEvent:
+				if joystick := joysticks[int(t.Which)]; joystick != nil {
+					joystick.Close()
+				}
+				fmt.Println("Joystick", t.Which, "disconnected")
+			}
+		}
+
+		sdl.Delay(16)
+	}
+
+	return
+}
+
+func main() {
+	if err := run(); err != nil {
+		os.Exit(1)
+	}
+}