ebiten: Add Vibrate and VibrateOptions, and implement this on browsers

Updates #1452

examples/vibrate/main.go

@@ -0,0 +1,65 @@
+// Copyright 2021 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build example
+// +build example
+
+package main
+
+import (
+	"log"
+	"time"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
+	"github.com/hajimehoshi/ebiten/v2/inpututil"
+)
+
+const (
+	screenWidth  = 640
+	screenHeight = 480
+)
+
+type Game struct {
+	touchIDs []ebiten.TouchID
+}
+
+func (g *Game) Update() error {
+	g.touchIDs = g.touchIDs[:0]
+	g.touchIDs = inpututil.AppendJustPressedTouchIDs(g.touchIDs)
+	if len(g.touchIDs) > 0 {
+		op := &ebiten.VibrateOptions{
+			Duration:        200 * time.Millisecond,
+			StrongMagnitude: 1,
+		}
+		ebiten.Vibrate(op)
+	}
+
+	return nil
+}
+
+func (g *Game) Draw(screen *ebiten.Image) {
+	ebitenutil.DebugPrint(screen, "Touch the screen to vibrate the screen.")
+}
+
+func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
+	return screenWidth, screenHeight
+}
+
+func main() {
+	ebiten.SetWindowTitle("Vibrate (Ebiten Demo)")
+	if err := ebiten.RunGame(&Game{}); err != nil {
+		log.Fatal(err)
+	}
+}

internal/driver/ui.go

@@ -17,6 +17,7 @@ package driver
 import (
 	"errors"
 	"image"
+	"time"
 )
 
 type UIContext interface {
@@ -62,6 +63,8 @@ type UI interface {
 	SetScreenTransparent(transparent bool)
 	SetInitFocused(focused bool)
 
+	Vibrate(duration time.Duration, strongMagnitude float64, weakMagnitude float64)
+
 	Input() Input
 	Window() Window
 	Graphics() Graphics

internal/uidriver/glfw/ui.go

@@ -1685,3 +1685,7 @@ func (u *UserInterface) setOrigPos(x, y int) {
 	u.origPosX = x
 	u.origPosY = y
 }
+
+func (u *UserInterface) Vibrate(duration time.Duration, strongMagnitude float64, weakMagnitude float64) {
+	// Do nothing.
+}

internal/uidriver/js/ui_js.go

@@ -648,6 +648,12 @@ func (u *UserInterface) SetInitFocused(focused bool) {
 	u.initFocused = focused
 }
 
+func (u *UserInterface) Vibrate(duration time.Duration, strongMagnitude float64, weakMagnitude float64) {
+	if js.Global().Get("navigator").Get("vibrate").Truthy() {
+		js.Global().Get("navigator").Call("vibrate", float64(duration/time.Millisecond))
+	}
+}
+
 func (u *UserInterface) Input() driver.Input {
 	return &u.input
 }

internal/uidriver/mobile/ui.go

@@ -492,3 +492,7 @@ func (u *UserInterface) ScheduleFrame() {
 		u.renderRequester.RequestRenderIfNeeded()
 	}
 }
+
+func (u *UserInterface) Vibrate(duration time.Duration, strongMagnitude float64, weakMagnitude float64) {
+	// TODO: Implement this (#1452)
+}

vibrate.go

@@ -0,0 +1,43 @@
+// Copyright 2021 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ebiten
+
+import (
+	"time"
+)
+
+// VibrateOptions represents the options to vibrate a device.
+type VibrateOptions struct {
+	// Duration is the time duration of the effect.
+	Duration time.Duration
+
+	// StrongMagnitude is the rumble intensity of a low-frequency rumble motor.
+	// The value is in between 0 and 1.
+	StrongMagnitude float64
+
+	// StrongMagnitude is the rumble intensity of a high-frequency rumble motor.
+	// The value is in between 0 and 1.
+	WeakMagnitude float64
+}
+
+// Vibrate vibrates the device.
+//
+// Vibrate works on mobiles and browsers.
+// On browsers, StrongManitude and WeakMagnitude might be ignored.
+//
+// Vibrate is concurrent-safe.
+func Vibrate(options *VibrateOptions) {
+	uiDriver().Vibrate(options.Duration, options.StrongMagnitude, options.WeakMagnitude)
+}