Improve example/gamepad

example/gamepad/main.go

@@ -15,6 +15,7 @@
 package main
 
 import (
+	"fmt"
 	"github.com/hajimehoshi/ebiten"
 	"github.com/hajimehoshi/ebiten/ebitenutil"
 	"log"
@@ -28,13 +29,29 @@ const (
 )
 
 func update(screen *ebiten.Image) error {
-	pressed := []string{}
+	const gamepadID = 0
-	for b := ebiten.GamepadButton(0); b < 16; b++ {
+	axes := []string{}
-		if ebiten.IsGamepadButtonPressed(0, b) {
+	pressedButtons := []string{}
-			pressed = append(pressed, strconv.Itoa(int(b)))
+
+	maxAxis := ebiten.GamepadAxisNum(gamepadID)
+	for a := 0; a < maxAxis; a++ {
+		v := ebiten.GamepadAxis(gamepadID, a)
+		axes = append(axes, fmt.Sprintf("%d: %0.6f", a, v))
+	}
+
+	maxButton := ebiten.GamepadButton(ebiten.GamepadButtonNum(gamepadID))
+	for b := ebiten.GamepadButton(gamepadID); b < maxButton; b++ {
+		if ebiten.IsGamepadButtonPressed(gamepadID, b) {
+			pressedButtons = append(pressedButtons, strconv.Itoa(int(b)))
 		}
 	}
-	str := "Pressed Keys: " + strings.Join(pressed, ", ")
+
+	str := `Gamepad
+  Axes:
+    {{.Axes}}
+  Pressed Buttons: {{.Buttons}}`
+	str = strings.Replace(str, "{{.Axes}}", strings.Join(axes, "\n    "), -1)
+	str = strings.Replace(str, "{{.Buttons}}", strings.Join(pressedButtons, ", "), -1)
 	ebitenutil.DebugPrint(screen, str)
 	return nil
 }

gamecontext.go

@@ -36,12 +36,22 @@ func IsMouseButtonPressed(mouseButton MouseButton) bool {
 	return ui.IsMouseButtonPressed(ui.MouseButton(mouseButton))
 }
 
-func GamepadAxis(j int, dir int) float64 {
+// TODO: docs
-	return ui.GamepadAxis(j, dir)
+
+func GamepadAxisNum(id int) int {
+	return ui.GamepadAxisNum(id)
 }
 
-func IsGamepadButtonPressed(j int, button GamepadButton) bool {
+func GamepadAxis(id int, axis int) float64 {
-	return ui.IsGamepadButtonPressed(j, ui.GamepadButton(button))
+	return ui.GamepadAxis(id, axis)
+}
+
+func GamepadButtonNum(id int) int {
+	return ui.GamepadButtonNum(id)
+}
+
+func IsGamepadButtonPressed(id int, button GamepadButton) bool {
+	return ui.IsGamepadButtonPressed(id, ui.GamepadButton(button))
 }
 
 // NewImage returns an empty image.

internal/ui/input.go

@@ -26,18 +26,32 @@ func IsMouseButtonPressed(button MouseButton) bool {
 	return currentInput.mouseButtonPressed[button]
 }
 
-func GamepadAxis(j int, dir int) float64 {
+func GamepadAxisNum(id int) int {
-	if len(currentInput.gamepads) <= j {
+	if len(currentInput.gamepads) <= id {
 		return 0
 	}
-	return currentInput.gamepads[j].axes[dir]
+	return currentInput.gamepads[id].axisNum
 }
 
-func IsGamepadButtonPressed(j int, button GamepadButton) bool {
+func GamepadAxis(id int, axis int) float64 {
-	if len(currentInput.gamepads) <= j {
+	if len(currentInput.gamepads) <= id {
+		return 0
+	}
+	return currentInput.gamepads[id].axes[axis]
+}
+
+func GamepadButtonNum(id int) int {
+	if len(currentInput.gamepads) <= id {
+		return 0
+	}
+	return currentInput.gamepads[id].buttonNum
+}
+
+func IsGamepadButtonPressed(id int, button GamepadButton) bool {
+	if len(currentInput.gamepads) <= id {
 		return false
 	}
-	return currentInput.gamepads[j].buttonPressed[button]
+	return currentInput.gamepads[id].buttonPressed[button]
 }
 
 var currentInput input
@@ -51,6 +65,8 @@ type input struct {
 }
 
 type gamePad struct {
-	axes          [2]float64
+	axisNum       int
+	axes          [16]float64
+	buttonNum     int
 	buttonPressed [256]bool
 }

internal/ui/input_glfw.go

@@ -45,6 +45,7 @@ func (i *input) update(window *glfw.Window, scale int) error {
 		if err != nil {
 			return err
 		}
+		i.gamepads[j].axisNum = len(axes32)
 		for a := 0; a < len(i.gamepads[j].axes); a++ {
 			if len(axes32) <= a {
 				i.gamepads[j].axes[a] = 0
@@ -56,6 +57,7 @@ func (i *input) update(window *glfw.Window, scale int) error {
 		if err != nil {
 			return err
 		}
+		i.gamepads[j].buttonNum = len(buttons)
 		for b := 0; b < len(i.gamepads[j].buttonPressed); b++ {
 			if len(buttons) <= b {
 				i.gamepads[j].buttonPressed[b] = false