Add menu stuff

src/gui/context.cpp

@@ -199,6 +199,12 @@ void gui::Context::DrawText(std::string_view text, const glm::vec2& pos, uint32_
     }
 }
 
+void gui::Context::DrawTextAligned(std::string_view text, const glm::vec2& pos, const glm::vec2& align, uint32_t color, float scale)
+{
+    auto size = MeasureText(text) * scale;
+    DrawText(text, pos + size * align, color, scale);
+}
+
 void gui::Context::Render()
 {
     va_.SetVBOData(vertices_.data(), vertices_.size() * sizeof(vertices_[0]));

src/gui/context.hpp

@@ -36,6 +36,7 @@ public:
 
     glm::vec2 MeasureText(std::string_view text);
     void DrawText(std::string_view text, const glm::vec2& pos, uint32_t color = 0xFFFFFFFF, float scale = 1.0f);
+    void DrawTextAligned(std::string_view text, const glm::vec2& pos, const glm::vec2& align, uint32_t color = 0xFFFFFFFF, float scale = 1.0f);
 
     void Render();
 

src/gui/menu.cpp

@@ -0,0 +1,120 @@
+#include "menu.hpp"
+
+#include <cstring>
+
+// Menu
+
+void gui::Menu::Draw(Context& ctx, const glm::vec2& pos) const
+{
+    // TODO: draw bg
+
+    glm::vec2 cursor = pos;
+    
+    for (size_t i = 0; i < items_.size(); ++i)
+    {
+        items_[i]->Draw(DrawMenuItemArgs(ctx, cursor, focus_ == i));
+        cursor.y += items_[i]->GetSize().y;
+    }
+}
+
+void gui::Menu::Input(MenuInput in)
+{
+    switch (in)
+    {
+    case MI_UP:
+        SwitchFocus(-1);
+        break;
+
+    case MI_DOWN:
+        SwitchFocus(1);
+        break;
+
+    default:
+        if (!items_.empty())
+            items_[focus_]->Input(in);
+        break;
+    }
+}
+
+glm::vec2 gui::Menu::MeasureSize() const
+{
+    glm::vec2 size(0.0f);
+
+    for (const auto& item : items_)
+    {
+        const auto& itemsize = item->GetSize();
+        size.x = glm::max(size.x, itemsize.x);
+        size.y += itemsize.y;
+    }
+
+    return size;
+}
+
+void gui::Menu::SwitchFocus(int dir)
+{
+    if (items_.empty())
+        return;
+
+    focus_ = (focus_ + items_.size() + dir) % items_.size();
+}
+
+// ButtonMenuItem
+
+gui::ButtonMenuItem::ButtonMenuItem(std::string text, std::function<void()> click_cb)
+    : text_(std::move(text)), click_cb_(std::move(click_cb))
+{
+    size_ = glm::vec2(500.0f, 30.0f);
+}
+
+void gui::ButtonMenuItem::Draw(const DrawMenuItemArgs& args) const
+{
+    Super::Draw(args);
+    glm::vec2 center = args.pos + glm::vec2(0.0f, size_.y * 0.5f);
+    args.ctx.DrawTextAligned(text_, center, glm::vec2(0.0f, -0.5f), args.focused ? COLOR_FOCUSED : COLOR_INACTIVE);
+}
+
+void gui::ButtonMenuItem::Input(MenuInput in)
+{
+    if (in == MI_ENTER && click_cb_)
+        click_cb_();
+}
+
+// SelectMenuItem
+
+gui::SelectMenuItem::SelectMenuItem(std::string text, std::function<void()> click_cb,
+                                    std::function<void(int)> switch_cb)
+    : ButtonMenuItem(std::move(text), std::move(click_cb)), switch_cb_(std::move(switch_cb))
+{
+}
+
+void gui::SelectMenuItem::Draw(const DrawMenuItemArgs& args) const
+{
+    Super::Draw(args);
+
+    char buffer[128];
+    size_t len = snprintf(buffer, sizeof(buffer), "< %s >", select_text_.c_str());
+
+    glm::vec2 center_right = args.pos + glm::vec2(size_.x, size_.y * 0.5f);
+    args.ctx.DrawTextAligned(std::string_view(buffer, len), center_right, glm::vec2(-1.0f, -0.5f),
+                             args.focused ? COLOR_FOCUSED : COLOR_INACTIVE);
+}
+
+void gui::SelectMenuItem::Input(MenuInput in)
+{
+    switch (in)
+    {
+    case MI_LEFT:
+        if (switch_cb_)
+            switch_cb_(-1);
+        break;
+
+    case MI_RIGHT:
+        if (switch_cb_)
+            switch_cb_(1);
+        break;
+
+    default:
+        Super::Input(in);
+        break;
+    }
+}

src/gui/menu.hpp

@@ -0,0 +1,119 @@
+#pragma once
+
+#include <vector>
+#include <concepts>
+
+#include "context.hpp"
+
+namespace gui
+{
+
+enum MenuInput
+{
+    MI_UP,
+    MI_DOWN,
+    MI_LEFT,
+    MI_RIGHT,
+    MI_BACK,
+    MI_ENTER,
+};
+
+class MenuItem;
+
+struct DrawMenuItemArgs
+{
+    Context& ctx;
+    glm::vec2 pos;
+    bool focused;
+
+    DrawMenuItemArgs(Context& ctx, const glm::vec2& pos, bool focused) : ctx(ctx), pos(pos), focused(focused) {}
+};
+
+class Menu
+{
+public:
+    Menu() = default;
+
+    template <std::derived_from<MenuItem> T, typename... TArgs>
+    T& Add(TArgs&&... args)
+    {
+        auto item = std::make_unique<T>(std::forward<TArgs>(args)...);
+        auto& item_ref = *item;
+        items_.emplace_back(std::move(item));
+        return item_ref;
+    }
+    
+    void Draw(Context& ctx, const glm::vec2& pos) const;
+    void Input(MenuInput in);
+
+    glm::vec2 MeasureSize() const;
+
+private:
+    void SwitchFocus(int dir);
+
+private:
+    std::vector<std::unique_ptr<MenuItem>> items_;
+    size_t focus_ = 0;
+
+};
+
+class MenuItem
+{
+public:
+    constexpr static uint32_t COLOR_INACTIVE = 0xFFFFFFFF;
+    constexpr static uint32_t COLOR_FOCUSED = 0xFF00FFFF;
+
+    MenuItem() = default;
+
+    virtual void Draw(const DrawMenuItemArgs& args) const {}
+    virtual void Input(MenuInput in) {}
+
+    const glm::vec2& GetSize() const { return size_; }
+
+    virtual ~MenuItem() = default;
+
+protected:
+    glm::vec2 size_;
+
+};
+
+class ButtonMenuItem : public MenuItem
+{
+public:
+    using Super = MenuItem;
+
+    ButtonMenuItem(std::string text, std::function<void()> click_cb);
+
+    virtual void Draw(const DrawMenuItemArgs& args) const override;
+    virtual void Input(MenuInput in) override;
+
+    virtual ~ButtonMenuItem() = default;
+
+private:
+    std::string text_;
+    std::function<void()> click_cb_;
+};
+
+class SelectMenuItem : public ButtonMenuItem
+{
+public:
+    using Super = ButtonMenuItem;
+
+    SelectMenuItem(std::string text, std::function<void()> click_cb, std::function<void(int)> switch_cb);
+
+    virtual void Draw(const DrawMenuItemArgs& args) const override;
+    virtual void Input(MenuInput in) override;
+
+    void SetSelectionText(std::string select_text) { select_text_ = std::move(select_text); }
+
+    virtual ~SelectMenuItem() = default;
+
+protected:
+    std::string select_text_;
+    std::function<void(int)> switch_cb_;
+
+};
+
+
+
+}