Numpad keys can now be used to move the cursor in text fields when Nu…

…m Lock is off and when using SDL >= 2.0.22 or GLFW >= 3.3 (closes #245)

changelog.md

@@ -5,6 +5,7 @@ TGUI 1.6 (TBD)
 - Added addMultipleItems to ListBox and ComboBox
 - Added getItemByIndex, getIndexById and getIdByIndex to ComboBox
 - Added setSpinButtonWidth function to SpinControl
+- Numpad keys may now move the cursor in text fields when Num Lock is off
 - setOrientation in Slider or SpinButton will no longer flip width and height
 - setSize in Slider or SpinButton no longer affects orientation once setOrientation is called
 - Fixed crash on exit when tool tip was visible

include/TGUI/Backend/Window/BackendGui.hpp

@@ -648,6 +648,13 @@ TGUI_MODULE_EXPORT namespace tgui
         /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
         virtual void updateContainerSize();
 
+        /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+        // Used when the NumLock is off to translate keypad key events to key events for text cursor navigation.
+        // The key parameter should be a value from Numpad0 to Numpad9 and the output is the key code that corresponds to the
+        // wanted functionality (e.g. for Numpad0 we return the Insert key). Unknown is returned for Numpad5.
+        /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+        Event::KeyboardKey translateKeypadKey(Event::KeyboardKey key);
+
         /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
     public:
 

include/TGUI/extlibs/IncludeSDL.hpp

@@ -74,6 +74,9 @@
     #define SDL_KMOD_SHIFT KMOD_SHIFT
     #define SDL_KMOD_LSHIFT KMOD_LSHIFT
     #define SDL_KMOD_RSHIFT KMOD_RSHIFT
+    #define SDL_KMOD_CAPS KMOD_CAPS
+    #define SDL_KMOD_NUM KMOD_NUM
+    #define SDL_KMOD_SCROLL KMOD_SCROLL
 #endif
 
 #if SDL_MAJOR_VERSION < 2

src/Backend/Window/BackendGui.cpp

@@ -691,6 +691,35 @@ TGUI_IGNORE_DEPRECATED_WARNINGS_END
     }
 
     /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+    Event::KeyboardKey BackendGui::translateKeypadKey(Event::KeyboardKey key)
+    {
+        switch (key)
+        {
+        case Event::KeyboardKey::Numpad0:
+            return Event::KeyboardKey::Insert;
+        case Event::KeyboardKey::Numpad1:
+            return Event::KeyboardKey::End;
+        case Event::KeyboardKey::Numpad2:
+            return Event::KeyboardKey::Down;
+        case Event::KeyboardKey::Numpad3:
+            return Event::KeyboardKey::PageDown;
+        case Event::KeyboardKey::Numpad4:
+            return Event::KeyboardKey::Left;
+        case Event::KeyboardKey::Numpad6:
+            return Event::KeyboardKey::Right;
+        case Event::KeyboardKey::Numpad7:
+            return Event::KeyboardKey::Home;
+        case Event::KeyboardKey::Numpad8:
+            return Event::KeyboardKey::Up;
+        case Event::KeyboardKey::Numpad9:
+            return Event::KeyboardKey::PageUp;
+        default: // Event::KeyboardKey::Numpad5
+            return Event::KeyboardKey::Unknown; // Let's ignore this key press
+        };
+    }
+
+    /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 }
 
 /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

src/Backend/Window/GLFW/BackendGuiGLFW.cpp

@@ -317,6 +317,21 @@ namespace tgui
         event.key.control = ((mods & GLFW_MOD_CONTROL) != 0);
         event.key.shift = ((mods & GLFW_MOD_SHIFT) != 0);
         event.key.system = ((mods & GLFW_MOD_SUPER) != 0);
+
+        // If the NumLock is off then we will translate keypad key events to key events for text cursor navigation.
+        // The state of the NumLock key is only available since GLFW 3.3 and only when the GLFW_LOCK_KEY_MODS input mode is enabled.
+#if GLFW_VERSION_MAJOR > 3 || (GLFW_VERSION_MAJOR == 3 && GLFW_VERSION_MINOR >= 3)
+        static_assert(static_cast<int>(Event::KeyboardKey::Numpad0) + 9 == static_cast<int>(Event::KeyboardKey::Numpad9), "Numpad0 to Numpad9 need continous ids in KeyboardKey");
+        if ((static_cast<int>(event.key.code) >= static_cast<int>(Event::KeyboardKey::Numpad0))
+         && (static_cast<int>(event.key.code) <= static_cast<int>(Event::KeyboardKey::Numpad9))
+         && ((mods & GLFW_MOD_NUM_LOCK) == 0) && (glfwGetInputMode(m_window, GLFW_LOCK_KEY_MODS) == GLFW_TRUE))
+        {
+            event.key.code = translateKeypadKey(event.key.code);
+            if (event.key.code == Event::KeyboardKey::Unknown) // Numpad5 was pressed which has no function
+                return {}; // We didn't handle this key press
+        }
+#endif
+
         return event;
     }
 
@@ -503,6 +518,11 @@ namespace tgui
         getBackend()->attachGui(this);
         std::static_pointer_cast<BackendGLFW>(getBackend())->setGuiWindow(this, window);
 
+#if GLFW_VERSION_MAJOR > 3 || (GLFW_VERSION_MAJOR == 3 && GLFW_VERSION_MINOR >= 3)
+        // We want to know the state of the num lock key
+        glfwSetInputMode(window, GLFW_LOCK_KEY_MODS, GLFW_TRUE);
+#endif
+
         updateContainerSize();
     }
 

src/Backend/Window/SDL/BackendGuiSDL.cpp

@@ -272,27 +272,34 @@ namespace tgui
             case SDL_EVENT_KEY_DOWN:
             {
 #if SDL_MAJOR_VERSION >= 3
+                const std::uint16_t modifiers = eventSDL.key.mod;
                 const Event::KeyboardKey code = convertKeyCode(eventSDL.key.key);
-                if (code == Event::KeyboardKey::Unknown)
-                    return false; // This key isn't handled by TGUI
-
-                eventTGUI.type = Event::Type::KeyPressed;
-                eventTGUI.key.code = code;
-                eventTGUI.key.alt = ((eventSDL.key.mod & SDL_KMOD_ALT) != 0);
-                eventTGUI.key.control = ((eventSDL.key.mod & SDL_KMOD_CTRL) != 0);
-                eventTGUI.key.shift = ((eventSDL.key.mod & SDL_KMOD_SHIFT) != 0);
-                eventTGUI.key.system = ((eventSDL.key.mod & SDL_KMOD_GUI) != 0);
 #else
+                const std::uint16_t modifiers = eventSDL.key.keysym.mod;
                 const Event::KeyboardKey code = convertKeyCode(eventSDL.key.keysym.sym);
+#endif
                 if (code == Event::KeyboardKey::Unknown)
                     return false; // This key isn't handled by TGUI
 
                 eventTGUI.type = Event::Type::KeyPressed;
                 eventTGUI.key.code = code;
-                eventTGUI.key.alt = ((eventSDL.key.keysym.mod & SDL_KMOD_ALT) != 0);
-                eventTGUI.key.control = ((eventSDL.key.keysym.mod & SDL_KMOD_CTRL) != 0);
-                eventTGUI.key.shift = ((eventSDL.key.keysym.mod & SDL_KMOD_SHIFT) != 0);
-                eventTGUI.key.system = ((eventSDL.key.keysym.mod & SDL_KMOD_GUI) != 0);
+                eventTGUI.key.alt = ((modifiers & SDL_KMOD_ALT) != 0);
+                eventTGUI.key.control = ((modifiers & SDL_KMOD_CTRL) != 0);
+                eventTGUI.key.shift = ((modifiers & SDL_KMOD_SHIFT) != 0);
+                eventTGUI.key.system = ((modifiers & SDL_KMOD_GUI) != 0);
+
+                // If the NumLock is off then we will translate keypad key events to key events for text cursor navigation.
+                // We only do this for SDL 2.0.22 or newer, because the NumLock state was incorrect on Linux prior to this version.
+#if (SDL_MAJOR_VERSION > 2) || ((SDL_MAJOR_VERSION == 2) && (SDL_MINOR_VERSION > 0)) || ((SDL_MAJOR_VERSION == 2) && (SDL_MINOR_VERSION == 0) && (SDL_PATCHLEVEL >= 22))
+                static_assert(static_cast<int>(Event::KeyboardKey::Numpad0) + 9 == static_cast<int>(Event::KeyboardKey::Numpad9), "Numpad0 to Numpad9 need continous ids in KeyboardKey");
+                if (((modifiers & SDL_KMOD_NUM) == 0)
+                 && (static_cast<int>(eventTGUI.key.code) >= static_cast<int>(Event::KeyboardKey::Numpad0))
+                 && (static_cast<int>(eventTGUI.key.code) <= static_cast<int>(Event::KeyboardKey::Numpad9)))
+                {
+                    eventTGUI.key.code = translateKeypadKey(eventTGUI.key.code);
+                    if (eventTGUI.key.code == Event::KeyboardKey::Unknown) // Numpad5 was pressed which has no function
+                        return false; // We didn't handle this key press
+                }
 #endif
                 return true;
             }

src/Backend/Window/SFML/BackendGuiSFML.cpp

@@ -406,7 +406,7 @@ namespace tgui
             m_modifierKeyShiftPressed = eventKeyPressed->shift;
             m_modifierKeyAltPressed = eventKeyPressed->alt;
 
-            // When pressing a modifier key, the modifier state in the KeyEvent is still false
+            // When pressing a modifier key, the modifier state in the KeyEvent may still be false
             if ((eventKeyPressed->code == sf::Keyboard::Key::LSystem) || (eventKeyPressed->code == sf::Keyboard::Key::RSystem))
                 m_modifierKeySystemPressed = true;
             else if ((eventKeyPressed->code == sf::Keyboard::Key::LControl) || (eventKeyPressed->code == sf::Keyboard::Key::RControl))
@@ -422,6 +422,20 @@ namespace tgui
             eventTGUI.key.control = eventKeyPressed->control;
             eventTGUI.key.shift = eventKeyPressed->shift;
             eventTGUI.key.system = eventKeyPressed->system;
+
+            // If the NumLock is off then we will translate keypad key events to key events for text cursor navigation.
+            // This functionality is not yet part of SFML, but is available in PR #3238 (https://github.com/SFML/SFML/pull/3238)
+#if 0
+            static_assert(static_cast<int>(Event::KeyboardKey::Numpad0) + 9 == static_cast<int>(Event::KeyboardKey::Numpad9), "Numpad0 to Numpad9 need continous ids in KeyboardKey");
+            if (!eventKeyPressed->numLock
+             && (static_cast<int>(eventTGUI.key.code) >= static_cast<int>(Event::KeyboardKey::Numpad0))
+             && (static_cast<int>(eventTGUI.key.code) <= static_cast<int>(Event::KeyboardKey::Numpad9)))
+            {
+                eventTGUI.key.code = translateKeypadKey(eventTGUI.key.code);
+                if (eventTGUI.key.code == Event::KeyboardKey::Unknown) // Numpad5 was pressed which has no function
+                    return false; // We didn't handle this key press
+            }
+#endif
             return true;
         }
 
@@ -432,7 +446,7 @@ namespace tgui
             m_modifierKeyShiftPressed = eventKeyReleased->shift;
             m_modifierKeyAltPressed = eventKeyReleased->alt;
 
-            // When releasing a modifier key, the modifier state in the KeyEvent is still true
+            // When releasing a modifier key, the modifier state in the KeyEvent may still be true
             if ((eventKeyReleased->code == sf::Keyboard::Key::LSystem) || (eventKeyReleased->code == sf::Keyboard::Key::RSystem))
                 m_modifierKeySystemPressed = false;
             else if ((eventKeyReleased->code == sf::Keyboard::Key::LControl) || (eventKeyReleased->code == sf::Keyboard::Key::RControl))