feat(ui): add TextField widget with UTF-8 text input support

include/Cubed/scene/scene.hpp

@@ -36,5 +36,8 @@ protected:
         return false;
     }
     virtual bool handle_key_event(const KeyEvent&) { return false; }
+    virtual bool handle_text_input_event(const TextInputEvent&) {
+        return false;
+    }
 };
 } // namespace Cubed

include/Cubed/tools/text_tools.hpp

@@ -0,0 +1,41 @@
+#pragma once
+#include <cstdint>
+#include <string>
+namespace Cubed {
+inline std::string codepoint_to_utf8(uint32_t cp) {
+    std::string out;
+
+    if (cp <= 0x7F) {
+        out.push_back(static_cast<char>(cp));
+    } else if (cp <= 0x7FF) {
+        out.push_back(static_cast<char>(0xC0 | (cp >> 6)));
+        out.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    } else if (cp <= 0xFFFF) {
+        out.push_back(static_cast<char>(0xE0 | (cp >> 12)));
+        out.push_back(static_cast<char>(0x80 | ((cp >> 6) & 0x3F)));
+        out.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    } else {
+        out.push_back(static_cast<char>(0xF0 | (cp >> 18)));
+        out.push_back(static_cast<char>(0x80 | ((cp >> 12) & 0x3F)));
+        out.push_back(static_cast<char>(0x80 | ((cp >> 6) & 0x3F)));
+        out.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    }
+
+    return out;
+}
+
+inline void utf8_pop_back(std::string& str) {
+    if (str.empty()) {
+        return;
+    }
+
+    std::size_t i = str.size() - 1;
+
+    while (i > 0 && (static_cast<unsigned char>(str[i]) & 0xC0) == 0x80) {
+        --i;
+    }
+
+    str.erase(i);
+}
+
+} // namespace Cubed

include/Cubed/ui/text_field.hpp

@@ -0,0 +1,65 @@
+#pragma once
+
+#include "Cubed/ui/image.hpp"
+#include "Cubed/ui/label.hpp"
+#include "Cubed/ui/widget.hpp"
+namespace Cubed {
+class TextField : public Widget {
+public:
+    TextField(const TextField&) = delete;
+    TextField(TextField&&) = delete;
+    TextField& operator=(const TextField&) = delete;
+    TextField& operator=(TextField&&) = delete;
+    TextField(Widget* parent);
+
+    TextField& set_scale(float scale);
+
+    float width() const override;
+    float height() const override;
+
+    TextField& set_width(float width);
+    TextField& set_height(float height);
+    TextField& set_show_text(const std::string& text);
+    TextField& set_background_image(const std::string& path,
+                                    TextureManager& texture_manager);
+    TextField& set_default_image(TextureManager& texture_manager);
+    TextField& set_auto_scale(bool auto_scale);
+    bool handle_mouse_move_event(const MouseMoveEvent& e) override;
+    bool handle_mouse_button_event(const MouseButtonEvent& e) override;
+    bool handle_text_input_event(const TextInputEvent& e) override;
+    bool handle_key_event(const KeyEvent& e) override;
+
+    const std::string& input_text() const;
+
+    template <typename F> TextField& set_on_finish(F&& f) {
+        m_on_finished = std::forward<F>(f);
+        return *this;
+    }
+
+private:
+    static constexpr float PADDING = 5.0f;
+    static constexpr float DEFAULT_SCALE = 3.0f;
+    static constexpr float TEXT_SCALE = 0.6f;
+
+    static constexpr const char* DEFAULT_TEXT_FIELD_IMAGE =
+        "texture/ui/textfield001.png";
+    std::unique_ptr<Image> m_background;
+    std::unique_ptr<Label> m_foreground;
+    bool m_inside = false;
+    bool m_typing = false;
+    bool m_auto_scale = false;
+
+    float m_width = NORMAL_TEXTFIELD_WIDTH;
+    float m_height = NORMAL_TEXTFIELD_HEIGHT;
+    float m_scale = DEFAULT_SCALE;
+
+    std::string m_input_text;
+    std::string m_show_text;
+
+    std::function<void()> m_on_finished;
+    void update_text_scale();
+    void on_render(Renderer& renderer) override;
+    void on_update(float dt) override;
+    void update_show_text();
+};
+} // namespace Cubed

include/Cubed/ui/ui_manager.hpp

@@ -26,6 +26,7 @@ public:
     virtual bool handle_window_resize_event(const WindowResizeEvent& e);
     virtual bool handle_mouse_wheel_event(const MouseWheelEvent& e);
     virtual bool handle_key_event(const KeyEvent& e);
+    virtual bool handle_text_input_event(const TextInputEvent& e);
 
 protected:
     std::unique_ptr<Widget> m_root_widget;

include/Cubed/ui/widget.hpp

@@ -12,10 +12,16 @@ constexpr float NORMAL_BUTTON_WIDTH = 225.0f;
 constexpr float NORMAL_BUTTON_HEIGHT = 20.0f;
 constexpr float NORMAL_SLIDER_WIDTH = 225.0f;
 constexpr float NORMAL_SLIDER_HEIGHT = 20.0f;
-
+constexpr float NORMAL_TEXTFIELD_WIDTH = 225.0f;
+constexpr float NORMAL_TEXTFIELD_HEIGHT = 20.0f;
 class Widget {
 
 public:
+    Widget(const Widget&) = delete;
+    Widget(Widget&&) = delete;
+    Widget& operator=(const Widget&) = delete;
+    Widget& operator=(Widget&&) = delete;
+
     Widget(const std::string& id, Widget* parent);
     Widget(Widget* parent);
     virtual ~Widget() = default;
@@ -35,7 +41,7 @@ public:
     virtual bool handle_mouse_wheel_event(const MouseWheelEvent& e);
     virtual bool handle_window_resize_event(const WindowResizeEvent& e);
     virtual bool handle_mouse_move_event(const MouseMoveEvent& e);
-
+    virtual bool handle_text_input_event(const TextInputEvent& e);
     template <typename T, typename... Args> T& add_child(Args&&... args) {
         auto widget = std::make_unique<T>(std::forward<Args>(args)..., this);
         T& ref = *widget;