ebiten: Add VibrationOptions to specify intensity (#1891)

Updates #1452

examples/vibrate/main.go

@@ -32,15 +32,21 @@ const (
 )
 
 type Game struct {
-	touchIDs   []ebiten.TouchID
-	gamepadIDs []ebiten.GamepadID
+	touchIDs     []ebiten.TouchID
+	gamepadIDs   []ebiten.GamepadID
+	touchCounter int
 }
 
 func (g *Game) Update() error {
 	g.touchIDs = g.touchIDs[:0]
 	g.touchIDs = inpututil.AppendJustPressedTouchIDs(g.touchIDs)
 	if len(g.touchIDs) > 0 {
-		ebiten.Vibrate(200 * time.Millisecond)
+		g.touchCounter++
+		op := &ebiten.VibrateOptions{
+			Duration:  200 * time.Millisecond,
+			Intensity: 0.5*float64(g.touchCounter%2) + 0.5,
+		}
+		ebiten.Vibrate(op)
 	}
 
 	g.gamepadIDs = g.gamepadIDs[:0]

internal/driver/ui.go

@@ -63,7 +63,7 @@ type UI interface {
 	SetScreenTransparent(transparent bool)
 	SetInitFocused(focused bool)
 
-	Vibrate(duration time.Duration)
+	Vibrate(duration time.Duration, intensity float64)
 
 	Input() Input
 	Window() Window

internal/uidriver/glfw/ui.go

@@ -1673,6 +1673,6 @@ func (u *UserInterface) setOrigPos(x, y int) {
 	u.origPosY = y
 }
 
-func (u *UserInterface) Vibrate(duration time.Duration) {
+func (u *UserInterface) Vibrate(duration time.Duration, intensity float64) {
 	// Do nothing.
 }

internal/uidriver/js/ui_js.go

@@ -648,7 +648,9 @@ func (u *UserInterface) SetInitFocused(focused bool) {
 	u.initFocused = focused
 }
 
-func (u *UserInterface) Vibrate(duration time.Duration) {
+func (u *UserInterface) Vibrate(duration time.Duration, intensity float64) {
+	// intensity is ignored.
+
 	if js.Global().Get("navigator").Get("vibrate").Truthy() {
 		js.Global().Get("navigator").Call("vibrate", float64(duration/time.Millisecond))
 	}

internal/uidriver/mobile/vibrate_android.go

@@ -21,30 +21,41 @@ import (
 )
 
 /*
-
 #include <jni.h>
 #include <stdlib.h>
 #include <stdint.h>
 
+#include <android/log.h>
+
 // Basically same as:
 //
 //     Vibrator v = (Vibrator)getSystemService(Context.VIBRATOR_SERVICE);
-//     v.vibrate(millisecond)
-//
-// TODO: As of API Level 26, the new API should be Used instead:
-//
-//     Vibrator v = (Vibrator)getSystemService(Context.VIBRATOR_SERVICE);
-//     v.vibrate(VibrationEffect.createOneShot(millisecond, VibrationEffect.DEFAULT_AMPLITUDE))
+//     if (Build.VERSION.SDK_INT >= 26) {
+//       v.vibrate(VibrationEffect.createOneShot(milliseconds, intensity * 255))
+//     } else {
+//       v.vibrate(millisecond)
+//     }
 //
 // Note that this requires a manifest setting:
 //
 //     <uses-permission android:name="android.permission.VIBRATE"/>
 //
-static void vibrateOneShot(uintptr_t java_vm, uintptr_t jni_env, uintptr_t ctx, int64_t milliseconds) {
+static void vibrateOneShot(uintptr_t java_vm, uintptr_t jni_env, uintptr_t ctx, int64_t milliseconds, double intensity) {
   JavaVM* vm = (JavaVM*)java_vm;
   JNIEnv* env = (JNIEnv*)jni_env;
   jobject context = (jobject)ctx;
 
+  static int apiLevel = 0;
+  if (!apiLevel) {
+    const jclass android_os_Build_VERSION = (*env)->FindClass(env, "android/os/Build$VERSION");
+
+    apiLevel = (*env)->GetStaticIntField(
+        env, android_os_Build_VERSION,
+        (*env)->GetStaticFieldID(env, android_os_Build_VERSION, "SDK_INT", "I"));
+
+    (*env)->DeleteLocalRef(env, android_os_Build_VERSION);
+  }
+
   const jclass android_content_Context = (*env)->FindClass(env, "android/content/Context");
   const jclass android_os_Vibrator = (*env)->FindClass(env, "android/os/Vibrator");
 
@@ -59,10 +70,29 @@ static void vibrateOneShot(uintptr_t java_vm, uintptr_t jni_env, uintptr_t ctx,
           (*env)->GetMethodID(env, android_content_Context, "getSystemService", "(Ljava/lang/String;)Ljava/lang/Object;"),
           android_context_Context_VIBRATOR_SERVICE);
 
-  (*env)->CallVoidMethod(
-      env, vibrator,
-      (*env)->GetMethodID(env, android_os_Vibrator, "vibrate", "(J)V"),
-      milliseconds);
+  if (apiLevel >= 26) {
+    const jclass android_os_VibrationEffect = (*env)->FindClass(env, "android/os/VibrationEffect");
+
+    const jobject vibrationEffect =
+        (*env)->CallStaticObjectMethod(
+            env, android_os_VibrationEffect,
+            (*env)->GetStaticMethodID(env, android_os_VibrationEffect, "createOneShot", "(JI)Landroid/os/VibrationEffect;"),
+            milliseconds, (int)(intensity * 255));
+
+    (*env)->CallVoidMethod(
+        env, vibrator,
+        (*env)->GetMethodID(env, android_os_Vibrator, "vibrate", "(Landroid/os/VibrationEffect;)V"),
+        vibrationEffect);
+
+    (*env)->DeleteLocalRef(env, android_os_VibrationEffect);
+
+    (*env)->DeleteLocalRef(env, vibrationEffect);
+  } else {
+    (*env)->CallVoidMethod(
+        env, vibrator,
+        (*env)->GetMethodID(env, android_os_Vibrator, "vibrate", "(J)V"),
+        milliseconds);
+  }
 
   (*env)->DeleteLocalRef(env, android_content_Context);
   (*env)->DeleteLocalRef(env, android_os_Vibrator);
@@ -74,10 +104,10 @@ static void vibrateOneShot(uintptr_t java_vm, uintptr_t jni_env, uintptr_t ctx,
 */
 import "C"
 
-func (u *UserInterface) Vibrate(duration time.Duration) {
+func (u *UserInterface) Vibrate(duration time.Duration, intensity float64) {
 	_ = app.RunOnJVM(func(vm, env, ctx uintptr) error {
 		// TODO: This might be crash when this is called from init(). How can we detect this?
-		C.vibrateOneShot(C.uintptr_t(vm), C.uintptr_t(env), C.uintptr_t(ctx), C.int64_t(duration/time.Millisecond))
+		C.vibrateOneShot(C.uintptr_t(vm), C.uintptr_t(env), C.uintptr_t(ctx), C.int64_t(duration/time.Millisecond), C.double(intensity))
 		return nil
 	})
 }

internal/uidriver/mobile/vibrate_ios.go

@@ -42,7 +42,7 @@ package mobile
 //   return nil;
 // }
 //
-// static void vibrate(double duration) {
+// static void vibrate(double duration, double intensity) {
 //   if (@available(iOS 13.0, *)) {
 //     static BOOL initializeHapticEngineCalled = NO;
 //     static CHHapticEngine* engine = nil;
@@ -64,7 +64,7 @@ package mobile
 //               (id<NSCopying>)(CHHapticPatternKeyEventParameters):@[
 //                 @{
 //                   (id<NSCopying>)(CHHapticPatternKeyParameterID): CHHapticEventParameterIDHapticIntensity,
-//                   (id<NSCopying>)(CHHapticPatternKeyParameterValue): @1.0,
+//                   (id<NSCopying>)(CHHapticPatternKeyParameterValue): [NSNumber numberWithDouble:intensity],
 //                 },
 //               ],
 //             },
@@ -103,9 +103,9 @@ import (
 
 var vibrationM sync.Mutex
 
-func (u *UserInterface) Vibrate(duration time.Duration) {
+func (u *UserInterface) Vibrate(duration time.Duration, intensity float64) {
 	vibrationM.Lock()
 	defer vibrationM.Unlock()
 
-	C.vibrate(C.double(float64(duration) / float64(time.Second)))
+	C.vibrate(C.double(float64(duration)/float64(time.Second)), C.double(intensity))
 }

vibrate.go

@@ -18,20 +18,38 @@ import (
 	"time"
 )
 
-// Vibrate vibrates the device.
+// VibrateOptions represents the options for device vibration.
+type VibrateOptions struct {
+	// Duration is the time duration of the effect.
+	Duration time.Duration
+
+	// Intensity is the strength of the device vibration.
+	// The value is in between 0 and 1.
+	Intensity float64
+}
+
+// Vibrate vibrates the device with the specified options.
 //
 // Vibrate works on mobiles and browsers.
 //
+// On browsers, Intensity in the options is ignored.
+//
 // On Android, this line is required in the manifest setting to use the vibration:
 //
 //     <uses-permission android:name="android.permission.VIBRATE"/>
 //
+// On Android, Intensity in the options is recognized only when the API Level is 26 or newer.
+// Otherwise, Intensity is ignored.
+//
+// On iOS, Vibrate works only when iOS version is 13.0 or newer.
+// Otherwise, Vibrate does nothing.
+//
 // Vibrate is concurrent-safe.
-func Vibrate(duration time.Duration) {
-	uiDriver().Vibrate(duration)
+func Vibrate(options *VibrateOptions) {
+	uiDriver().Vibrate(options.Duration, options.Intensity)
 }
 
-// VibrateGamepadOptions represents the options to vibrate a gamepad.
+// VibrateGamepadOptions represents the options for gamepad vibration.
 type VibrateGamepadOptions struct {
 	// Duration is the time duration of the effect.
 	Duration time.Duration