mobile/ebitenmobileview: Implement Android gamepad buttons

This is still work in progress.

Updates #1083

cmd/ebitenmobile/gobind.go

@@ -334,49 +334,57 @@ const viewJava = `// Code generated by ebitenmobile. DO NOT EDIT.
 package {{.JavaPkg}}.{{.PrefixLower}};
 
 import android.content.Context;
+import android.hardware.input.InputManager;
 import android.os.Handler;
 import android.os.Looper;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.KeyEvent;
+import android.view.InputDevice;
 import android.view.MotionEvent;
 import android.view.ViewGroup;
 
 import {{.JavaPkg}}.ebitenmobileview.Ebitenmobileview;
 
-public class EbitenView extends ViewGroup {
+public class EbitenView extends ViewGroup implements InputManager.InputDeviceListener {
     private double getDeviceScale() {
-        if (deviceScale_ == 0.0) {
+        if (this.deviceScale == 0.0) {
-            deviceScale_ = getResources().getDisplayMetrics().density;
+            this.deviceScale = getResources().getDisplayMetrics().density;
         }
-        return deviceScale_;
+        return this.deviceScale;
     }
 
     private double pxToDp(double x) {
         return x / getDeviceScale();
     }
 
-    private double deviceScale_ = 0.0;
+    private double deviceScale = 0.0;
 
     public EbitenView(Context context) {
         super(context);
-        initialize();
+        initialize(context);
     }
 
     public EbitenView(Context context, AttributeSet attrs) {
         super(context, attrs);
-        initialize();
+        initialize(context);
     }
 
-    private void initialize() {
+    private void initialize(Context context) {
-        ebitenSurfaceView_ = new EbitenSurfaceView(getContext());
+        this.ebitenSurfaceView = new EbitenSurfaceView(getContext());
         LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
-        addView(ebitenSurfaceView_, params);
+        addView(this.ebitenSurfaceView, params);
+
+        this.inputManager = (InputManager)context.getSystemService(Context.INPUT_SERVICE);
+        this.inputManager.registerInputDeviceListener(this, null);
+        for (int id : this.inputManager.getInputDeviceIds()) {
+            this.onInputDeviceAdded(id);
+        }
     }
 
     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
-        ebitenSurfaceView_.layout(0, 0, right - left, bottom - top);
+        this.ebitenSurfaceView.layout(0, 0, right - left, bottom - top);
         double widthInDp = pxToDp(right - left);
         double heightInDp = pxToDp(bottom - top);
         Ebitenmobileview.layout(widthInDp, heightInDp);
@@ -384,13 +392,13 @@ public class EbitenView extends ViewGroup {
 
     @Override
     public boolean onKeyDown(int keyCode, KeyEvent event) {
-        Ebitenmobileview.onKeyDownOnAndroid(keyCode, event.getUnicodeChar());
+        Ebitenmobileview.onKeyDownOnAndroid(keyCode, event.getUnicodeChar(), event.getSource(), event.getDeviceId());
         return true;
     }
 
     @Override
     public boolean onKeyUp(int keyCode, KeyEvent event) {
-        Ebitenmobileview.onKeyUpOnAndroid(keyCode);
+        Ebitenmobileview.onKeyUpOnAndroid(keyCode, event.getSource(), event.getDeviceId());
         return true;
     }
 
@@ -405,11 +413,82 @@ public class EbitenView extends ViewGroup {
         return true;
     }
 
+    // The order must be the same as mobile/ebitenmobileview/input_android.go.
+    static int[] gamepadButtons = {
+        KeyEvent.KEYCODE_BUTTON_A,
+        KeyEvent.KEYCODE_BUTTON_B,
+        KeyEvent.KEYCODE_BUTTON_C,
+        KeyEvent.KEYCODE_BUTTON_X,
+        KeyEvent.KEYCODE_BUTTON_Y,
+        KeyEvent.KEYCODE_BUTTON_Z,
+        KeyEvent.KEYCODE_BUTTON_L1,
+        KeyEvent.KEYCODE_BUTTON_R1,
+        KeyEvent.KEYCODE_BUTTON_L2,
+        KeyEvent.KEYCODE_BUTTON_R2,
+        KeyEvent.KEYCODE_BUTTON_THUMBL,
+        KeyEvent.KEYCODE_BUTTON_THUMBR,
+        KeyEvent.KEYCODE_BUTTON_START,
+        KeyEvent.KEYCODE_BUTTON_SELECT,
+        KeyEvent.KEYCODE_BUTTON_MODE,
+        KeyEvent.KEYCODE_BUTTON_1,
+        KeyEvent.KEYCODE_BUTTON_2,
+        KeyEvent.KEYCODE_BUTTON_3,
+        KeyEvent.KEYCODE_BUTTON_4,
+        KeyEvent.KEYCODE_BUTTON_5,
+        KeyEvent.KEYCODE_BUTTON_6,
+        KeyEvent.KEYCODE_BUTTON_7,
+        KeyEvent.KEYCODE_BUTTON_8,
+        KeyEvent.KEYCODE_BUTTON_9,
+        KeyEvent.KEYCODE_BUTTON_10,
+        KeyEvent.KEYCODE_BUTTON_11,
+        KeyEvent.KEYCODE_BUTTON_12,
+        KeyEvent.KEYCODE_BUTTON_13,
+        KeyEvent.KEYCODE_BUTTON_14,
+        KeyEvent.KEYCODE_BUTTON_15,
+        KeyEvent.KEYCODE_BUTTON_16,
+    };
+
+    @Override
+    public void onInputDeviceAdded(int deviceId) {
+        InputDevice inputDevice = this.inputManager.getInputDevice(deviceId);
+        int sources = inputDevice.getSources();
+        if ((sources & InputDevice.SOURCE_GAMEPAD) != InputDevice.SOURCE_GAMEPAD &&
+            (sources & InputDevice.SOURCE_JOYSTICK) != InputDevice.SOURCE_JOYSTICK) {
+            return;
+        }
+        boolean[] keyExistences = inputDevice.hasKeys(gamepadButtons);
+        int buttonNum = gamepadButtons.length - 1;
+        for (int i = gamepadButtons.length - 1; i >= 0; i--) {
+            if (keyExistences[i]) {
+                break;
+            }
+            buttonNum--;
+        }
+        Ebitenmobileview.onGamepadAdded(deviceId, inputDevice.getName(), buttonNum);
+    }
+
+    @Override
+    public void onInputDeviceChanged(int deviceId) {
+        // Do nothing.
+    }
+
+    @Override
+    public void onInputDeviceRemoved(int deviceId) {
+        InputDevice inputDevice = this.inputManager.getInputDevice(deviceId);
+        int sources = inputDevice.getSources();
+        if ((sources & InputDevice.SOURCE_GAMEPAD) != InputDevice.SOURCE_GAMEPAD &&
+            (sources & InputDevice.SOURCE_JOYSTICK) != InputDevice.SOURCE_JOYSTICK) {
+            return;
+        }
+        Ebitenmobileview.onGamepadRemoved(deviceId);
+    }
+
     // suspendGame suspends the game.
     // It is recommended to call this when the application is being suspended e.g.,
     // Activity's onPause is called.
     public void suspendGame() {
-        ebitenSurfaceView_.onPause();
+        this.inputManager.unregisterInputDeviceListener(this);
+        this.ebitenSurfaceView.onPause();
         Ebitenmobileview.suspend();
     }
 
@@ -417,7 +496,8 @@ public class EbitenView extends ViewGroup {
     // It is recommended to call this when the application is being resumed e.g.,
     // Activity's onResume is called.
     public void resumeGame() {
-        ebitenSurfaceView_.onResume();
+        this.inputManager.registerInputDeviceListener(this, null);
+        this.ebitenSurfaceView.onResume();
         Ebitenmobileview.resume();
     }
 
@@ -427,7 +507,8 @@ public class EbitenView extends ViewGroup {
         Log.e("Go", e.toString());
     }
 
-    private EbitenSurfaceView ebitenSurfaceView_;
+    private EbitenSurfaceView ebitenSurfaceView;
+    private InputManager inputManager;
 }
 `
 
@@ -440,6 +521,7 @@ import android.opengl.GLSurfaceView;
 import android.os.Handler;
 import android.os.Looper;
 import android.util.AttributeSet;
+import android.util.Log;
 
 import javax.microedition.khronos.egl.EGLConfig;
 import javax.microedition.khronos.opengles.GL10;
@@ -499,7 +581,5 @@ class EbitenSurfaceView extends GLSurfaceView {
     private void onErrorOnGameUpdate(Exception e) {
         ((EbitenView)getParent()).onErrorOnGameUpdate(e);
     }
-
-    private double deviceScale_ = 0.0;
 }
 `

internal/driver/gamepadbutton.go

@@ -50,3 +50,5 @@ const (
 	GamepadButton30
 	GamepadButton31
 )
+
+const GamepadButtonNum = 32

internal/uidriver/mobile/input.go

@@ -26,12 +26,13 @@ type pos struct {
 }
 
 type Input struct {
-	cursorX int
+	cursorX  int
-	cursorY int
+	cursorY  int
-	keys    map[driver.Key]struct{}
+	keys     map[driver.Key]struct{}
-	runes   []rune
+	runes    []rune
-	touches map[int]pos
+	touches  map[int]pos
-	ui      *UserInterface
+	gamepads []Gamepad
+	ui       *UserInterface
 }
 
 func (i *Input) CursorPosition() (x, y int) {
@@ -41,30 +42,78 @@ func (i *Input) CursorPosition() (x, y int) {
 }
 
 func (i *Input) GamepadIDs() []int {
-	return nil
+	i.ui.m.RLock()
+	defer i.ui.m.RUnlock()
+
+	ids := make([]int, 0, len(i.gamepads))
+	for _, g := range i.gamepads {
+		ids = append(ids, g.ID)
+	}
+	return ids
 }
 
 func (i *Input) GamepadSDLID(id int) string {
+	i.ui.m.RLock()
+	defer i.ui.m.RUnlock()
+
+	for _, g := range i.gamepads {
+		if g.ID != id {
+			continue
+		}
+		return g.SDLID
+	}
 	return ""
 }
 
 func (i *Input) GamepadName(id int) string {
+	i.ui.m.RLock()
+	defer i.ui.m.RUnlock()
+
+	for _, g := range i.gamepads {
+		if g.ID != id {
+			continue
+		}
+		return g.Name
+	}
 	return ""
 }
 
 func (i *Input) GamepadAxisNum(id int) int {
+	// TODO: Implement this
 	return 0
 }
 
 func (i *Input) GamepadAxis(id int, axis int) float64 {
+	// TODO: Implement this
 	return 0
 }
 
 func (i *Input) GamepadButtonNum(id int) int {
+	i.ui.m.RLock()
+	defer i.ui.m.RUnlock()
+
+	for _, g := range i.gamepads {
+		if g.ID != id {
+			continue
+		}
+		return g.ButtonNum
+	}
 	return 0
 }
 
 func (i *Input) IsGamepadButtonPressed(id int, button driver.GamepadButton) bool {
+	i.ui.m.RLock()
+	defer i.ui.m.RUnlock()
+
+	for _, g := range i.gamepads {
+		if g.ID != id {
+			continue
+		}
+		if g.ButtonNum <= int(button) {
+			return false
+		}
+		return g.Buttons[button]
+	}
 	return false
 }
 
@@ -118,7 +167,7 @@ func (i *Input) IsMouseButtonPressed(key driver.MouseButton) bool {
 	return false
 }
 
-func (i *Input) update(keys map[driver.Key]struct{}, runes []rune, touches []*Touch) {
+func (i *Input) update(keys map[driver.Key]struct{}, runes []rune, touches []*Touch, gamepads []Gamepad) {
 	i.ui.m.Lock()
 	defer i.ui.m.Unlock()
 
@@ -137,6 +186,9 @@ func (i *Input) update(keys map[driver.Key]struct{}, runes []rune, touches []*To
 			Y: t.Y,
 		}
 	}
+
+	i.gamepads = make([]Gamepad, len(gamepads))
+	copy(i.gamepads, gamepads)
 }
 
 func (i *Input) ResetForFrame() {

internal/uidriver/mobile/ui.go

@@ -229,7 +229,7 @@ func (u *UserInterface) appMain(a app.App) {
 			for _, t := range touches {
 				ts = append(ts, t)
 			}
-			u.input.update(keys, runes, ts)
+			u.input.update(keys, runes, ts, nil)
 		}
 	}
 }
@@ -451,6 +451,14 @@ type Touch struct {
 	Y  int
 }
 
-func (u *UserInterface) UpdateInput(keys map[driver.Key]struct{}, runes []rune, touches []*Touch) {
+type Gamepad struct {
-	u.input.update(keys, runes, touches)
+	ID        int
+	SDLID     string
+	Name      string
+	Buttons   [driver.GamepadButtonNum]bool
+	ButtonNum int
+}
+
+func (u *UserInterface) UpdateInput(keys map[driver.Key]struct{}, runes []rune, touches []*Touch, gamepads []Gamepad) {
+	u.input.update(keys, runes, touches, gamepads)
 }

mobile/ebitenmobileview/input.go

@@ -27,9 +27,10 @@ type position struct {
 }
 
 var (
-	keys    = map[driver.Key]struct{}{}
+	keys     = map[driver.Key]struct{}{}
-	runes   []rune
+	runes    []rune
-	touches = map[int]position{}
+	touches  = map[int]position{}
+	gamepads = map[int]*mobile.Gamepad{}
 )
 
 func updateInput() {
@@ -41,5 +42,11 @@ func updateInput() {
 			Y:  position.y,
 		})
 	}
-	mobile.Get().UpdateInput(keys, runes, ts)
+
+	gs := make([]mobile.Gamepad, 0, len(gamepads))
+	for _, g := range gamepads {
+		gs = append(gs, *g)
+	}
+
+	mobile.Get().UpdateInput(keys, runes, ts, gs)
 }

mobile/ebitenmobileview/input_android.go

@@ -16,8 +16,111 @@ package ebitenmobileview
 
 import (
 	"unicode"
+
+	"github.com/hajimehoshi/ebiten/internal/driver"
+	"github.com/hajimehoshi/ebiten/internal/uidriver/mobile"
 )
 
+// https://developer.android.com/reference/android/view/KeyEvent
+const (
+	keycodeButtonA      = 0x00000060
+	keycodeButtonB      = 0x00000061
+	keycodeButtonC      = 0x00000062
+	keycodeButtonX      = 0x00000063
+	keycodeButtonY      = 0x00000064
+	keycodeButtonZ      = 0x00000065
+	keycodeButtonL1     = 0x00000066
+	keycodeButtonR1     = 0x00000067
+	keycodeButtonL2     = 0x00000068
+	keycodeButtonR2     = 0x00000069
+	keycodeButtonThumbl = 0x0000006a
+	keycodeButtonThumbr = 0x0000006b
+	keycodeButtonStart  = 0x0000006c
+	keycodeButtonSelect = 0x0000006d
+	keycodeButtonMode   = 0x0000006e
+	keycodeButton1      = 0x000000bc
+	keycodeButton2      = 0x000000bd
+	keycodeButton3      = 0x000000be
+	keycodeButton4      = 0x000000bf
+	keycodeButton5      = 0x000000c0
+	keycodeButton6      = 0x000000c1
+	keycodeButton7      = 0x000000c2
+	keycodeButton8      = 0x000000c3
+	keycodeButton9      = 0x000000c4
+	keycodeButton10     = 0x000000c5
+	keycodeButton11     = 0x000000c6
+	keycodeButton12     = 0x000000c7
+	keycodeButton13     = 0x000000c8
+	keycodeButton14     = 0x000000c9
+	keycodeButton15     = 0x000000ca
+	keycodeButton16     = 0x000000cb
+)
+
+// https://developer.android.com/reference/android/view/InputDevice
+const (
+	sourceKeyboard = 0x00000101
+	sourceGamepad  = 0x00000401
+	sourceJoystick = 0x01000010
+)
+
+var androidKeyToGamepadButton = map[int]driver.GamepadButton{
+	keycodeButtonA:      driver.GamepadButton0,
+	keycodeButtonB:      driver.GamepadButton1,
+	keycodeButtonC:      driver.GamepadButton2,
+	keycodeButtonX:      driver.GamepadButton3,
+	keycodeButtonY:      driver.GamepadButton4,
+	keycodeButtonZ:      driver.GamepadButton5,
+	keycodeButtonL1:     driver.GamepadButton6,
+	keycodeButtonR1:     driver.GamepadButton7,
+	keycodeButtonL2:     driver.GamepadButton8,
+	keycodeButtonR2:     driver.GamepadButton9,
+	keycodeButtonThumbl: driver.GamepadButton10,
+	keycodeButtonThumbr: driver.GamepadButton11,
+	keycodeButtonStart:  driver.GamepadButton12,
+	keycodeButtonSelect: driver.GamepadButton13,
+	keycodeButtonMode:   driver.GamepadButton14,
+	keycodeButton1:      driver.GamepadButton15,
+	keycodeButton2:      driver.GamepadButton16,
+	keycodeButton3:      driver.GamepadButton17,
+	keycodeButton4:      driver.GamepadButton18,
+	keycodeButton5:      driver.GamepadButton19,
+	keycodeButton6:      driver.GamepadButton20,
+	keycodeButton7:      driver.GamepadButton21,
+	keycodeButton8:      driver.GamepadButton22,
+	keycodeButton9:      driver.GamepadButton23,
+	keycodeButton10:     driver.GamepadButton24,
+	keycodeButton11:     driver.GamepadButton25,
+	keycodeButton12:     driver.GamepadButton26,
+	keycodeButton13:     driver.GamepadButton27,
+	keycodeButton14:     driver.GamepadButton28,
+	keycodeButton15:     driver.GamepadButton29,
+	keycodeButton16:     driver.GamepadButton30,
+}
+
+var (
+	// deviceIDToGamepadID is a map from Android device IDs to Ebiten gamepad IDs.
+	// As convention, Ebiten gamepad IDs start with 0, and many applications depend on this fact.
+	deviceIDToGamepadID = map[int]int{}
+)
+
+func gamepadIDFromDeviceID(deviceID int) int {
+	if id, ok := deviceIDToGamepadID[deviceID]; ok {
+		return id
+	}
+	ids := map[int]struct{}{}
+	for _, id := range deviceIDToGamepadID {
+		ids[id] = struct{}{}
+	}
+	for i := 0; ; i++ {
+		if _, ok := ids[i]; ok {
+			continue
+		}
+		deviceIDToGamepadID[deviceID] = i
+		return i
+	}
+	panic("ebitenmobileview: a gamepad ID cannot be determined")
+}
+
 func UpdateTouchesOnAndroid(action int, id int, x, y int) {
 	switch action {
 	case 0x00, 0x05, 0x02: // ACTION_DOWN, ACTION_POINTER_DOWN, ACTION_MOVE
@@ -35,23 +138,66 @@ func UpdateTouchesOnIOS(phase int, ptr int64, x, y int) {
 	panic("ebitenmobileview: updateTouchesOnIOSImpl must not be called on Android")
 }
 
-func OnKeyDownOnAndroid(keyCode int, unicodeChar int) {
+func OnKeyDownOnAndroid(keyCode int, unicodeChar int, source int, deviceID int) {
-	key, ok := androidKeyToDriverKey[keyCode]
+	switch {
-	if !ok {
+	case source&sourceGamepad == sourceGamepad:
-		return
+		// A gamepad can be detected as a keyboard. Detect the device as a gamepad first.
+		if button, ok := androidKeyToGamepadButton[keyCode]; ok {
+			id := gamepadIDFromDeviceID(deviceID)
+			if _, ok := gamepads[id]; !ok {
+				// Can this happen?
+				gamepads[id] = &mobile.Gamepad{}
+			}
+			gamepads[id].Buttons[button] = true
+			updateInput()
+		}
+	case source&sourceJoystick == sourceJoystick:
+		// TODO: Handle DPAD keys
+	case source&sourceKeyboard == sourceKeyboard:
+		if key, ok := androidKeyToDriverKey[keyCode]; ok {
+			keys[key] = struct{}{}
+			if r := rune(unicodeChar); r != 0 && unicode.IsPrint(r) {
+				runes = []rune{r}
+			}
+			updateInput()
+		}
 	}
-	keys[key] = struct{}{}
-	if r := rune(unicodeChar); r != 0 && unicode.IsPrint(r) {
-		runes = []rune{r}
-	}
-	updateInput()
 }
 
-func OnKeyUpOnAndroid(keyCode int) {
+func OnKeyUpOnAndroid(keyCode int, source int, deviceID int) {
-	key, ok := androidKeyToDriverKey[keyCode]
+	switch {
-	if !ok {
+	case source&sourceGamepad == sourceGamepad:
-		return
+		// A gamepad can be detected as a keyboard. Detect the device as a gamepad first.
+		if button, ok := androidKeyToGamepadButton[keyCode]; ok {
+			id := gamepadIDFromDeviceID(deviceID)
+			if _, ok := gamepads[id]; !ok {
+				// Can this happen?
+				gamepads[id] = &mobile.Gamepad{}
+			}
+			gamepads[id].Buttons[button] = false
+			updateInput()
+		}
+	case source&sourceJoystick == sourceJoystick:
+		// TODO: Handle DPAD keys
+	case source&sourceKeyboard == sourceKeyboard:
+		if key, ok := androidKeyToDriverKey[keyCode]; ok {
+			delete(keys, key)
+			updateInput()
+		}
 	}
-	delete(keys, key)
+}
-	updateInput()
+
+func OnGamepadAdded(deviceID int, name string, buttonNum int) {
+	id := gamepadIDFromDeviceID(deviceID)
+	gamepads[id] = &mobile.Gamepad{
+		ID:        id,
+		SDLID:     "", // TODO: Implement this
+		Name:      name,
+		ButtonNum: buttonNum,
+	}
+}
+
+func OnGamepadRemoved(deviceID int) {
+	id := gamepadIDFromDeviceID(deviceID)
+	delete(gamepads, id)
 }