From 7389f9ddb22e6839fb21e0de37eeb50dce8213ce Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Tue, 12 Mar 2024 12:10:19 +0900
Subject: [PATCH] ebiten: add KeyIntlBackslash

Updates #2921
---
 genkeys.go                          | 15 ++++++++++++---
 internal/ui/keys.go                 |  3 +++
 internal/ui/keys_glfw.go            |  1 +
 internal/ui/keys_js.go              |  1 +
 keys.go                             |  7 +++++++
 mobile/ebitenmobileview/keys_ios.go |  2 +-
 6 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/genkeys.go b/genkeys.go
index a21f00f2b..bc0278d66 100644
--- a/genkeys.go
+++ b/genkeys.go
@@ -140,9 +140,17 @@ func init() {
 		"NumpadSubtract": "KPSubtract",
 		"NumpadEnter":    "KPEnter",
 		"NumpadEqual":    "KPEqual",
+		"IntlBackslash":  "World1",
 	}
 
 	// https://developer.android.com/reference/android/view/KeyEvent
+	//
+	// Android doesn't distinguish these keys:
+	// - a US backslash key (HID: 0x31),
+	// - an international pound/tilde key (HID: 0x32), and
+	// - an international backslash key (HID: 0x64).
+	// These are mapped to the same key code KEYCODE_BACKSLASH (73).
+	// See https://source.android.com/docs/core/interaction/input/keyboard-devices
 	androidKeyToUIKeyName = map[int]string{
 		55:  "Comma",
 		56:  "Period",
@@ -204,16 +212,16 @@ func init() {
 		0x35: "Backquote",
 
 		// These three keys are:
-		// - US backslash-pipe key (above return),
-		// - non-US backslash key (next to left shift; on German layout this is the <>| key), and
+		// - US backslash-pipe key, and
 		// - non-US hashmark key (bottom left of return; on German layout, this is the #' key).
 		// On US layout configurations, they all map to the same characters - the backslash.
 		//
 		// See also: https://www.w3.org/TR/uievents-code/#keyboard-102
 		0x31: "Backslash", // UIKeyboardHIDUsageKeyboardBackslash
-		0x64: "Backslash", // UIKeyboardHIDUsageKeyboardNonUSBackslash
 		0x32: "Backslash", // UIKeyboardHIDUsageKeyboardNonUSPound
 
+		0x64: "IntlBackslash", // UIKeyboardHIDUsageKeyboardNonUSBackslash
+
 		0x2A: "Backspace",
 		0x2F: "BracketLeft",
 		0x30: "BracketRight",
@@ -326,6 +334,7 @@ func init() {
 		"NumpadEqual":    "NumpadEqual",
 		"MetaLeft":       "MetaLeft",
 		"MetaRight":      "MetaRight",
+		"IntlBackslash":  "IntlBackslash",
 	}
 
 	const (
diff --git a/internal/ui/keys.go b/internal/ui/keys.go
index b0b4118d5..59bdcab77 100644
--- a/internal/ui/keys.go
+++ b/internal/ui/keys.go
@@ -106,6 +106,7 @@ const (
 	KeyF24
 	KeyHome
 	KeyInsert
+	KeyIntlBackslash
 	KeyMetaLeft
 	KeyMetaRight
 	KeyMinus
@@ -315,6 +316,8 @@ func (k Key) String() string {
 		return "KeyHome"
 	case KeyInsert:
 		return "KeyInsert"
+	case KeyIntlBackslash:
+		return "KeyIntlBackslash"
 	case KeyMetaLeft:
 		return "KeyMetaLeft"
 	case KeyMetaRight:
diff --git a/internal/ui/keys_glfw.go b/internal/ui/keys_glfw.go
index 96a273cf6..37af13b49 100644
--- a/internal/ui/keys_glfw.go
+++ b/internal/ui/keys_glfw.go
@@ -89,6 +89,7 @@ var uiKeyToGLFWKey = map[Key]glfw.Key{
 	KeyHome:           glfw.KeyHome,
 	KeyI:              glfw.KeyI,
 	KeyInsert:         glfw.KeyInsert,
+	KeyIntlBackslash:  glfw.KeyWorld1,
 	KeyJ:              glfw.KeyJ,
 	KeyK:              glfw.KeyK,
 	KeyL:              glfw.KeyL,
diff --git a/internal/ui/keys_js.go b/internal/ui/keys_js.go
index 26c3ea73f..e68203178 100644
--- a/internal/ui/keys_js.go
+++ b/internal/ui/keys_js.go
@@ -87,6 +87,7 @@ var uiKeyToJSCode = map[Key]js.Value{
 	KeyHome:           js.ValueOf("Home"),
 	KeyI:              js.ValueOf("KeyI"),
 	KeyInsert:         js.ValueOf("Insert"),
+	KeyIntlBackslash:  js.ValueOf("IntlBackslash"),
 	KeyJ:              js.ValueOf("KeyJ"),
 	KeyK:              js.ValueOf("KeyK"),
 	KeyL:              js.ValueOf("KeyL"),
diff --git a/keys.go b/keys.go
index 01f2c7447..e7a1fa82b 100644
--- a/keys.go
+++ b/keys.go
@@ -113,6 +113,7 @@ const (
 	KeyF24            Key = Key(ui.KeyF24)
 	KeyHome           Key = Key(ui.KeyHome)
 	KeyInsert         Key = Key(ui.KeyInsert)
+	KeyIntlBackslash  Key = Key(ui.KeyIntlBackslash)
 	KeyMetaLeft       Key = Key(ui.KeyMetaLeft)
 	KeyMetaRight      Key = Key(ui.KeyMetaRight)
 	KeyMinus          Key = Key(ui.KeyMinus)
@@ -365,6 +366,8 @@ func (k Key) isValid() bool {
 		return true
 	case KeyInsert:
 		return true
+	case KeyIntlBackslash:
+		return true
 	case KeyMeta:
 		return true
 	case KeyMetaLeft:
@@ -618,6 +621,8 @@ func (k Key) String() string {
 		return "Home"
 	case KeyInsert:
 		return "Insert"
+	case KeyIntlBackslash:
+		return "IntlBackslash"
 	case KeyMeta:
 		return "Meta"
 	case KeyMetaLeft:
@@ -892,6 +897,8 @@ func keyNameToKeyCode(name string) (Key, bool) {
 		return KeyHome, true
 	case "insert":
 		return KeyInsert, true
+	case "intlbackslash":
+		return KeyIntlBackslash, true
 	case "kp0":
 		return KeyKP0, true
 	case "kp1":
diff --git a/mobile/ebitenmobileview/keys_ios.go b/mobile/ebitenmobileview/keys_ios.go
index 2b16318fa..0f2ed24a5 100644
--- a/mobile/ebitenmobileview/keys_ios.go
+++ b/mobile/ebitenmobileview/keys_ios.go
@@ -117,7 +117,7 @@ var iosKeyToUIKey = map[int]ui.Key{
 	97:  ui.KeyNumpad9,
 	98:  ui.KeyNumpad0,
 	99:  ui.KeyNumpadDecimal,
-	100: ui.KeyBackslash,
+	100: ui.KeyIntlBackslash,
 	103: ui.KeyNumpadEqual,
 	104: ui.KeyF13,
 	105: ui.KeyF14,