Add support to click touchpad using back button on non PS4/5 controllers

README.md

@@ -102,7 +102,7 @@ PAD DOWN | DOWN |
 PAD LEFT | LEFT |
 PAD RIGHT | RIGHT |
 OPTIONS | RETURN |
-TOUCH PAD | SPACE |
+BACK BUTTON / TOUCH PAD | SPACE |
 L1 | Q |
 R1 | U |
 L2 | E |

src/common/config.cpp

@@ -41,6 +41,7 @@ static std::string logFilter;
 static std::string logType = "async";
 static std::string userName = "shadPS4";
 static std::string updateChannel;
+static std::string backButtonBehavior = "left";
 static bool useSpecialPad = false;
 static int specialPadClass = 1;
 static bool isDebugDump = false;
@@ -123,6 +124,10 @@ std::string getUpdateChannel() {
     return updateChannel;
 }
 
+std::string getBackButtonBehavior() {
+    return backButtonBehavior;
+}
+
 bool getUseSpecialPad() {
     return useSpecialPad;
 }
@@ -275,6 +280,10 @@ void setUpdateChannel(const std::string& type) {
     updateChannel = type;
 }
 
+void setBackButtonBehavior(const std::string& type) {
+    backButtonBehavior = type;
+}
+
 void setUseSpecialPad(bool use) {
     useSpecialPad = use;
 }
@@ -435,6 +444,7 @@ void load(const std::filesystem::path& path) {
         }
         isShowSplash = toml::find_or<bool>(general, "showSplash", true);
         isAutoUpdate = toml::find_or<bool>(general, "autoUpdate", false);
+        backButtonBehavior = toml::find_or<std::string>(general, "backButtonBehavior", "left");
     }
 
     if (data.contains("Input")) {
@@ -533,6 +543,7 @@ void save(const std::filesystem::path& path) {
     data["General"]["updateChannel"] = updateChannel;
     data["General"]["showSplash"] = isShowSplash;
     data["General"]["autoUpdate"] = isAutoUpdate;
+    data["General"]["backButtonBehavior"] = backButtonBehavior;
     data["Input"]["useSpecialPad"] = useSpecialPad;
     data["Input"]["specialPadClass"] = specialPadClass;
     data["GPU"]["screenWidth"] = screenWidth;
@@ -591,6 +602,7 @@ void setDefaultValues() {
     } else {
         updateChannel = "Nightly";
     }
+    backButtonBehavior = "left";
     useSpecialPad = false;
     specialPadClass = 1;
     isDebugDump = false;

src/common/config.h

@@ -20,6 +20,7 @@ std::string getLogFilter();
 std::string getLogType();
 std::string getUserName();
 std::string getUpdateChannel();
+std::string getBackButtonBehavior();
 
 bool getUseSpecialPad();
 int getSpecialPadClass();
@@ -54,6 +55,7 @@ void setLanguage(u32 language);
 void setNeoMode(bool enable);
 void setUserName(const std::string& type);
 void setUpdateChannel(const std::string& type);
+void setBackButtonBehavior(const std::string& type);
 
 void setUseSpecialPad(bool use);
 void setSpecialPadClass(int type);

src/qt_gui/settings_dialog.cpp

@@ -98,6 +98,15 @@ SettingsDialog::SettingsDialog(std::span<const QString> physical_devices, QWidge
     ui->buttonBox->button(QDialogButtonBox::RestoreDefaults)->setText(tr("Restore Defaults"));
     ui->buttonBox->button(QDialogButtonBox::Close)->setText(tr("Close"));
 
+    ui->backButtonBehaviorComboBox->addItem(tr("Touchpad Left"), "left");
+    ui->backButtonBehaviorComboBox->addItem(tr("Touchpad Center"), "center");
+    ui->backButtonBehaviorComboBox->addItem(tr("Touchpad Right"), "right");
+    ui->backButtonBehaviorComboBox->addItem(tr("None"), "none");
+
+    QString currentBackButtonBehavior = QString::fromStdString(Config::getBackButtonBehavior());
+    int index = ui->backButtonBehaviorComboBox->findData(currentBackButtonBehavior);
+    ui->backButtonBehaviorComboBox->setCurrentIndex(index != -1 ? index : 0);
+
     connect(ui->tabWidgetSettings, &QTabWidget::currentChanged, this,
             [this]() { ui->buttonBox->button(QDialogButtonBox::Close)->setFocus(); });
 
@@ -151,6 +160,14 @@ SettingsDialog::SettingsDialog(std::span<const QString> physical_devices, QWidge
             Config::setBGMvolume(val);
             BackgroundMusicPlayer::getInstance().setVolume(val);
         });
+
+        connect(ui->backButtonBehaviorComboBox, QOverload<int>::of(&QComboBox::currentIndexChanged),
+                this, [this](int index) {
+                    if (index >= 0 && index < ui->backButtonBehaviorComboBox->count()) {
+                        QString data = ui->backButtonBehaviorComboBox->itemData(index).toString();
+                        Config::setBackButtonBehavior(data.toStdString());
+                    }
+                });
     }
 
     // GPU TAB
@@ -204,6 +221,7 @@ SettingsDialog::SettingsDialog(std::span<const QString> physical_devices, QWidge
         ui->logFilter->installEventFilter(this);
         ui->updaterGroupBox->installEventFilter(this);
         ui->GUIgroupBox->installEventFilter(this);
+        ui->backButtonBehaviorGroupBox->installEventFilter(this);
 
         // Graphics
         ui->graphicsAdapterGroupBox->installEventFilter(this);
@@ -258,6 +276,10 @@ void SettingsDialog::LoadValuesFromConfig() {
         }
     }
     ui->updateComboBox->setCurrentText(QString::fromStdString(updateChannel));
+
+    QString backButtonBehavior = QString::fromStdString(Config::getBackButtonBehavior());
+    int index = ui->backButtonBehaviorComboBox->findData(backButtonBehavior);
+    ui->backButtonBehaviorComboBox->setCurrentIndex(index != -1 ? index : 0);
 }
 
 void SettingsDialog::InitializeEmulatorLanguages() {
@@ -319,6 +341,8 @@ void SettingsDialog::updateNoteTextEdit(const QString& elementName) {
         text = tr("updaterGroupBox");
     } else if (elementName == "GUIgroupBox") {
         text = tr("GUIgroupBox");
+    } else if (elementName == "backButtonBehaviorGroupBox") {
+        text = tr("backButtonBehaviorGroupBox");
     }
 
     // Graphics

src/qt_gui/settings_dialog.ui

@@ -442,20 +442,44 @@
            </layout>
           </item>
           <item>
-           <spacer name="horizontalSpacer">
-            <property name="orientation">
-             <enum>Qt::Orientation::Horizontal</enum>
-            </property>
-            <property name="sizeType">
-             <enum>QSizePolicy::Policy::Expanding</enum>
-            </property>
-            <property name="sizeHint" stdset="0">
-             <size>
-              <width>0</width>
-              <height>0</height>
-             </size>
-            </property>
-           </spacer>
+           <layout class="QVBoxLayout" name="ControllerTabLayoutRight" stretch="1">
+            <item>
+             <widget class="QGroupBox" name="ControllerGroupBox">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="MinimumExpanding" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="title">
+               <string>Controller Settings</string>
+              </property>
+              <widget class="QGroupBox" name="backButtonBehaviorGroupBox">
+               <property name="geometry">
+                <rect>
+                 <x>12</x>
+                 <y>30</y>
+                 <width>241</width>
+                 <height>65</height>
+                </rect>
+               </property>
+               <property name="title">
+                <string>Back Button Behavior</string>
+               </property>
+               <widget class="QComboBox" name="backButtonBehaviorComboBox">
+                <property name="geometry">
+                 <rect>
+                  <x>12</x>
+                  <y>30</y>
+                  <width>217</width>
+                  <height>28</height>
+                 </rect>
+                </property>
+               </widget>
+              </widget>
+             </widget>
+            </item>
+           </layout>
           </item>
          </layout>
         </item>

src/qt_gui/translations/en.ts

@@ -534,6 +534,16 @@
 			<source>Volume</source>
 			<translation>Volume</translation>
 		</message>
+		<message>
+			<location filename="../settings_dialog.ui" line="455"/>
+			<source>Controller Settings</source>
+			<translation>Controller Settings</translation>
+		</message>
+		<message>
+			<location filename="../settings_dialog.ui" line="467"/>
+			<source>Back Button Behavior</source>
+			<translation>Back Button Behavior</translation>
+		</message>
 	</context>
 	<context>
 		<name>MainWindow</name>
@@ -1023,6 +1033,31 @@
 			<source>GUIgroupBox</source>
 			<translation>Play Title Music:\nIf a game supports it, enable playing special music when selecting the game in the GUI.</translation>
 		</message>
+		<message>
+			<location filename="../settings_dialog.cpp" line="330"/>
+			<source>backButtonBehaviorGroupBox</source>
+			<translation>Back Button Behavior:\nAllows setting which part of the touchpad the back button will emulate a touch on.</translation>
+		</message>
+		<message>
+			<location filename="../settings_dialog.cpp" line="101"/>
+			<source>Touchpad Left</source>
+			<translation>Touchpad Left</translation>
+		</message>
+		<message>
+			<location filename="../settings_dialog.cpp" line="102"/>
+			<source>Touchpad Right</source>
+			<translation>Touchpad Right</translation>
+		</message>
+		<message>
+			<location filename="../settings_dialog.cpp" line="103"/>
+			<source>Touchpad Center</source>
+			<translation>Touchpad Center</translation>
+		</message>
+		<message>
+			<location filename="../settings_dialog.cpp" line="104"/>
+			<source>None</source>
+			<translation>None</translation>
+		</message>
 		<message>
 			<location filename="../settings_dialog.cpp" line="312"/>
 			<source>graphicsAdapterGroupBox</source>

src/sdl_window.cpp

@@ -145,6 +145,7 @@ void WindowSDL::onKeyPress(const SDL_Event* event) {
     Input::Axis axis = Input::Axis::AxisMax;
     int axisvalue = 0;
     int ax = 0;
+    std::string backButtonBehavior = Config::getBackButtonBehavior();
     switch (event->key.key) {
     case SDLK_UP:
         button = OrbisPadButtonDataOffset::ORBIS_PAD_BUTTON_UP;
@@ -278,7 +279,15 @@ void WindowSDL::onKeyPress(const SDL_Event* event) {
         ax = Input::GetAxis(0, 0x80, axisvalue);
         break;
     case SDLK_SPACE:
-        button = OrbisPadButtonDataOffset::ORBIS_PAD_BUTTON_TOUCH_PAD;
+        if (backButtonBehavior != "none") {
+            float x = backButtonBehavior == "left" ? 0.25f
+                                                   : (backButtonBehavior == "right" ? 0.75f : 0.5f);
+            // trigger a touchpad event so that the touchpad emulation for back button works
+            controller->SetTouchpadState(0, true, x, 0.5f);
+            button = OrbisPadButtonDataOffset::ORBIS_PAD_BUTTON_TOUCH_PAD;
+        } else {
+            button = 0;
+        }
         break;
     case SDLK_F11:
         if (event->type == SDL_EVENT_KEY_DOWN) {
@@ -330,7 +339,20 @@ void WindowSDL::onGamepadEvent(const SDL_Event* event) {
     case SDL_EVENT_GAMEPAD_BUTTON_UP:
         button = sdlGamepadToOrbisButton(event->gbutton.button);
         if (button != 0) {
-            controller->CheckButton(0, button, event->type == SDL_EVENT_GAMEPAD_BUTTON_DOWN);
+            if (event->gbutton.button == SDL_GAMEPAD_BUTTON_BACK) {
+                std::string backButtonBehavior = Config::getBackButtonBehavior();
+                if (backButtonBehavior != "none") {
+                    float x = backButtonBehavior == "left"
+                                  ? 0.25f
+                                  : (backButtonBehavior == "right" ? 0.75f : 0.5f);
+                    // trigger a touchpad event so that the touchpad emulation for back button works
+                    controller->SetTouchpadState(0, true, x, 0.5f);
+                    controller->CheckButton(0, button,
+                                            event->type == SDL_EVENT_GAMEPAD_BUTTON_DOWN);
+                }
+            } else {
+                controller->CheckButton(0, button, event->type == SDL_EVENT_GAMEPAD_BUTTON_DOWN);
+            }
         }
         if (SDL_GetCursor() != NULL) {
             SDL_HideCursor();