feat(renderer): add screenshot capture with F2

include/Cubed/render/renderer.hpp

@@ -25,7 +25,7 @@ class DevPanel;
 class Renderer {
 public:
     constexpr static int NUM_VAO = 7;
-
+    constexpr static const char* SCREENSHOT_PATH = "./screenshot";
     Renderer(TextureManager& texture_manager, Config& config);
     ~Renderer();
     void reload_config();
@@ -83,6 +83,8 @@ public:
 
     ModelRender& model_renderer();
 
+    void save_screenshot();
+
 private:
     TextureManager& m_texture_manager;
     bool m_init = false;
@@ -98,6 +100,8 @@ private:
     float m_window_width = 0.0f;
     float m_window_height = 0.0f;
 
+    bool m_save_screenshot = false;
+
     glm::mat4 m_world_proj_matrix;
 
     std::unique_ptr<VertexBuffer> m_sky_vbo;
@@ -129,6 +133,7 @@ private:
     void updata_framebuffer(int width, int height);
     void init_quad();
     void init_text();
+    void handle_screenshot();
 };
 
 } // namespace Cubed

include/Cubed/tools/time_tools.hpp

@@ -1,11 +1,23 @@
 #pragma once
 
 #include <SDL3/SDL_timer.h>
+#include <chrono>
 #include <cstdint>
+#include <format>
+#include <string>
 namespace Cubed {
 namespace Tools {
 // return ms
 inline uint64_t get_time_ticks() { return SDL_GetTicks(); }
+
+inline std::string get_time_date_str() {
+    static auto* zone = std::chrono::current_zone();
+    auto now = std::chrono::system_clock::now();
+    auto local =
+        std::chrono::time_point_cast<std::chrono::seconds>(zone->to_local(now));
+    return std::format("{:%F %T}", local);
+}
+
 } // namespace Tools
 
 } // namespace Cubed

src/render/renderer.cpp

@@ -9,10 +9,13 @@
 #include "Cubed/tools/font.hpp"
 #include "Cubed/tools/log.hpp"
 #include "Cubed/tools/shader_tools.hpp"
+#include "Cubed/tools/time_tools.hpp"
 
+#include <array>
 #include <format>
 #include <glm/gtc/type_ptr.hpp>
-
+#include <stb_image_write.h>
+namespace fs = std::filesystem;
 namespace Cubed {
 
 Renderer::Renderer(TextureManager& texture_manager, Config& config)
@@ -139,7 +142,7 @@ void Renderer::begin_frame() {
     glClearColor(0.0, 0.0, 0.0, 1.0);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 }
-void Renderer::end_frame() {}
+void Renderer::end_frame() { handle_screenshot(); }
 
 void Renderer::begin_render_ui() {
     glEnable(GL_BLEND);
@@ -288,6 +291,34 @@ bool Renderer::handle_frame_buffer_resize_event(
     return false;
 }
 
+void Renderer::handle_screenshot() {
+    if (!m_save_screenshot) {
+        return;
+    }
+    m_save_screenshot = false;
+    std::array<int, 4> screen_stats;
+    glGetIntegerv(GL_VIEWPORT, screen_stats.data());
+    int width = screen_stats[2];
+    int height = screen_stats[3];
+    std::vector<unsigned char> pixels(width * height * 4);
+    glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels.data());
+    std::vector<unsigned char> flipped_pixels(width * height * 4);
+    for (int y = 0; y < height; ++y) {
+        std::memcpy(&flipped_pixels[y * width * 4],
+                    &pixels[(height - 1 - y) * width * 4], width * 4);
+    }
+    fs::path path = SCREENSHOT_PATH;
+    fs::create_directories(path);
+    fs::path image =
+        path / std::format("screenshot {}.png", Tools::get_time_date_str());
+    if (!stbi_write_png(image.c_str(), width, height, 4, flipped_pixels.data(),
+                        width * 4)) {
+        Logger::error("Failed to write {} image", image.c_str());
+    } else {
+        Logger::info("save {} success!", image.c_str());
+    }
+}
+
 float& Renderer::ambient_strength() {
     return m_world_renderer.ambient_strength();
 }
@@ -341,4 +372,5 @@ float Renderer::frame_width() const { return m_frame_width; }
 const glm::mat4& Renderer::p_mat() const { return m_world_proj_matrix; }
 const std::vector<VertexArray>& Renderer::vao() const { return m_vao; }
 ModelRender& Renderer::model_renderer() { return m_model_renderer; }
+void Renderer::save_screenshot() { m_save_screenshot = true; }
 } // namespace Cubed

src/scene/world_scene.cpp

@@ -3,6 +3,7 @@
 #include "Cubed/app.hpp"
 #include "Cubed/render/renderer.hpp"
 #include "Cubed/scene/scene_manager.hpp"
+#include "Cubed/tools/time_tools.hpp"
 namespace Cubed {
 WorldScene::WorldScene(SceneManager& scene_manager)
     : m_scene_manager(scene_manager), m_dev_panel(*this),
@@ -380,7 +381,16 @@ bool WorldScene::handle_key_event(const KeyEvent& e) {
             }
         }
     }
-
+    if (e.key == Key::F2 && e.action == KeyAction::PRESS) {
+        m_scene_manager.app().renderer().save_screenshot();
+        ChatMessage msg;
+        msg.system_msg = true;
+        msg.color = Color::WHITE;
+        msg.text = "Saved Screenshot!";
+        msg.time = Tools::get_time_ticks();
+        m_hud_ui.add_chat_message(msg);
+        return true;
+    }
     if (m_paused) {
         switch (m_paused_ui) {
         case PauseUI::INVENTORY: