Merge pull request #174 from Dragonfly911117/runtime-config

Runtime config

Author: NOOBDY

CMakeLists.txt

@@ -28,6 +28,8 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/Dependencies.cmake)
 
 set(SRC_DIR ${CMAKE_CURRENT_SOURCE_DIR}/src)
 set(SRC_FILES
+    ${SRC_DIR}/config.cpp
+
     ${SRC_DIR}/Core/Context.cpp
     ${SRC_DIR}/Core/DebugMessageCallback.cpp
     ${SRC_DIR}/Core/VertexArray.cpp

cmake/Dependencies.cmake

@@ -76,6 +76,14 @@ FetchContent_Declare(
     SOURCE_DIR  ${CMAKE_CURRENT_SOURCE_DIR}/lib/imgui
 )
 
+FetchContent_Declare(
+    nlohmann_json
+
+    URL  https://github.com/nlohmann/json/releases/download/v3.11.3/json.tar.xz
+    URL_HASH MD5=c23a33f04786d85c29fda8d16b5f0efd
+    SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/lib/nlohmann_json
+)
+
 set(BUILD_SHARED_LIBS FALSE)
 
 set(SDL2IMAGE_INSTALL OFF)
@@ -94,10 +102,12 @@ set(SDL2MIXER_OGG OFF)
 set(SDL2MIXER_VORBIS OFF)
 set(SDL2MIXER_VOC OFF)
 
+set(JSON_ImplicitConversions OFF)
+
 # For Windows: Prevent overriding the parent project's compiler/linker settings
 set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
 
-FetchContent_MakeAvailable(sdl2 sdl2_image sdl2_ttf sdl2_mixer spdlog glm googletest)
+FetchContent_MakeAvailable(sdl2 sdl2_image sdl2_ttf sdl2_mixer spdlog glm googletest nlohmann_json)
 
 add_compile_definitions(GLEW_NO_GLU)
 
@@ -134,6 +144,7 @@ if (NOT ${imgui_POPULATED})
     )
 endif()
 
+
 set(DEPENDENCY_LINK_LIBRARIES
     ${OPENGL_LIBRARY}
     glew_s
@@ -146,6 +157,8 @@ set(DEPENDENCY_LINK_LIBRARIES
     spdlog::spdlog
 
     ImGui
+
+    nlohmann_json
 )
 
 set(DEPENDENCY_INCLUDE_DIRS
@@ -154,4 +167,5 @@ set(DEPENDENCY_INCLUDE_DIRS
     ${CMAKE_CURRENT_SOURCE_DIR}/lib/spdlog/include/
     ${CMAKE_CURRENT_SOURCE_DIR}/lib/glm/
     ${IMGUI_INCLUDE_DIR}
+    ${CMAKE_CURRENT_SOURCE_DIR}/lib/nlohmann_json/include/
 )

example/src/Giraffe.cpp

@@ -22,12 +22,12 @@ void Giraffe::Update() {
     auto &scale = m_Transform.scale;
     auto &rotation = m_Transform.rotation;
 
-    if (pos.y >= static_cast<float>(WINDOW_HEIGHT) / 2 ||
-        pos.y + static_cast<float>(WINDOW_HEIGHT) / 2 <= 0) {
+    if (pos.y >= static_cast<float>(PTSD_Config::WINDOW_HEIGHT) / 2 ||
+        pos.y + static_cast<float>(PTSD_Config::WINDOW_HEIGHT) / 2 <= 0) {
         dir.y *= -1;
     }
-    if (pos.x >= static_cast<float>(WINDOW_WIDTH) / 2 ||
-        pos.x + static_cast<float>(WINDOW_WIDTH) / 2 <= 0) {
+    if (pos.x >= static_cast<float>(PTSD_Config::WINDOW_WIDTH) / 2 ||
+        pos.x + static_cast<float>(PTSD_Config::WINDOW_WIDTH) / 2 <= 0) {
         dir.x *= -1;
     }
 

include/Core/Context.hpp

@@ -43,13 +43,12 @@ class Context {
     static std::shared_ptr<Context> s_Instance;
     bool m_Exit = false;
 
-    unsigned int m_WindowWidth = WINDOW_WIDTH;
-    unsigned int m_WindowHeight = WINDOW_HEIGHT;
+    unsigned int m_WindowWidth = PTSD_Config::WINDOW_WIDTH;
+    unsigned int m_WindowHeight = PTSD_Config::WINDOW_HEIGHT;
 
     // Can't access Time::s_Now, so using this variable to track time.
     Util::ms_t m_BeforeUpdateTime = Util::Time::GetElapsedTimeMs();
 };
-
 } // namespace Core
 
 #endif

include/config.hpp

@@ -1,25 +1,69 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 
+#include "Util/Logger.hpp"
 #include "pch.hpp" // IWYU pragma: export
 
-#include "Util/Logger.hpp"
+namespace Core {
+class Context;
+}
 
-constexpr const char *TITLE = "Practical Tools for Simple Design";
+// clang-format off
+/**
+    * To use, place a config.json file either in the current directory (.) or
+    * the parent directory (..). If both directories contain the file, the one
+    * in the current directory will be read.
+    *
+    * Example directory structure:
+    *
+    * @code{.md}
+    * ├── build/
+    * │   ├── YOUR_GAME
+    * │   └── config.json <- place here
+    * └── config.json <- or here
+    * @endcode
+    *
+    * The config.json file can contain any number of configurations, each in
+    * the following format:
+    *
+    * @code{.json}
+    * {
+    *   "title": "<string, default is 'Practice-Tools-for-Simple-Design'>",
+    *   "window_pos_x": <int, default is SDL_WINDOWPOS_UNDEFINED (wherever the OS places the window)>,
+    *   "window_pos_y": <int, default is SDL_WINDOWPOS_UNDEFINED (wherever the OS places the window)>,
+    *   "window_width": <int, default is 1280>,
+    *   "window_height": <int, default is 720>,
+    *   "default_log_level": <int in range [0, 5], default is 2 (Util::Logger::Level::INFO)>,
+    *   "fps_cap": <int, default is 60>
+    * }
+    * @endcode
+    *
+    * If a key is not present in the config.json, the default value will be
+    * used.
+    */
+// clang-format on
+struct PTSD_Config {
+public:
+    static std::string_view TITLE;
 
-constexpr int WINDOW_POS_X = SDL_WINDOWPOS_UNDEFINED;
-constexpr int WINDOW_POS_Y = SDL_WINDOWPOS_UNDEFINED;
+    static int WINDOW_POS_X;
 
-constexpr unsigned int WINDOW_WIDTH = 1280;
-constexpr unsigned int WINDOW_HEIGHT = 720;
+    static int WINDOW_POS_Y;
+    static unsigned int WINDOW_WIDTH;
 
-constexpr Util::Logger::Level DEFAULT_LOG_LEVEL = Util::Logger::Level::DEBUG;
+    static unsigned int WINDOW_HEIGHT;
+    static Util::Logger::Level DEFAULT_LOG_LEVEL;
 
-/**
- * @brief FPS limit
- *
- * Set value to 0 to turn off FPS cap
- */
-constexpr unsigned int FPS_CAP = 60;
+    /**
+     * @brief FPS limit
+     *
+     * Set value to 0 to turn off FPS cap
+     */
+    static unsigned int FPS_CAP;
+
+private:
+    friend class Core::Context;
+    static void Init();
+}; // namespace PTSD_Config
 
 #endif

include/pch.hpp

@@ -26,4 +26,6 @@
 #include <imgui_impl_opengl3.h>
 #include <imgui_impl_sdl2.h>
 
+#include <nlohmann/json.hpp>
+
 #endif

src/Core/Context.cpp

@@ -15,6 +15,8 @@ using Util::ms_t;
 namespace Core {
 Context::Context() {
     Util::Logger::Init();
+    PTSD_Config::Init();
+    Util::Logger::SetLevel(PTSD_Config::DEFAULT_LOG_LEVEL);
 
     if (SDL_Init(SDL_INIT_VIDEO) < 0) {
         LOG_ERROR("Failed to initialize SDL");
@@ -41,9 +43,10 @@ Context::Context() {
         LOG_ERROR(SDL_GetError());
     }
 
-    m_Window =
-        SDL_CreateWindow(TITLE, WINDOW_POS_X, WINDOW_POS_Y, WINDOW_WIDTH,
-                         WINDOW_HEIGHT, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
+    m_Window = SDL_CreateWindow(
+        PTSD_Config::TITLE.data(), PTSD_Config::WINDOW_POS_X,
+        PTSD_Config::WINDOW_POS_Y, PTSD_Config::WINDOW_WIDTH,
+        PTSD_Config::WINDOW_HEIGHT, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
 
     if (m_Window == nullptr) {
         LOG_ERROR("Failed to create window");
@@ -124,7 +127,8 @@ void Context::Update() {
     SDL_GL_SwapWindow(m_Window);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-    constexpr ms_t frameTime = FPS_CAP != 0 ? 1000.0F / FPS_CAP : 0;
+    static ms_t frameTime =
+        PTSD_Config::FPS_CAP != 0 ? 1000.0F / PTSD_Config::FPS_CAP : 0;
     ms_t afterUpdate = Util::Time::GetElapsedTimeMs();
     ms_t updateTime = afterUpdate - m_BeforeUpdateTime;
     if (updateTime < frameTime) {

src/Util/Input.cpp

@@ -81,9 +81,9 @@ void Input::Update() {
     s_CursorPosition.x = static_cast<float>(x);
     s_CursorPosition.y = static_cast<float>(y);
 
-    s_CursorPosition.x -= static_cast<float>(WINDOW_WIDTH) / 2;
-    s_CursorPosition.y =
-        -(s_CursorPosition.y - static_cast<float>(WINDOW_HEIGHT) / 2);
+    s_CursorPosition.x -= static_cast<float>(PTSD_Config::WINDOW_WIDTH) / 2;
+    s_CursorPosition.y = -(s_CursorPosition.y -
+                           static_cast<float>(PTSD_Config::WINDOW_HEIGHT) / 2);
 
     s_Scroll = s_MouseMoving = false;
 

src/Util/Logger.cpp

@@ -5,7 +5,7 @@
 namespace Util {
 void Logger::Init() {
     spdlog::set_pattern("%n [%^%l%$] %v");
-    SetLevel(DEFAULT_LOG_LEVEL);
+    SetLevel(Level::INFO);
 }
 
 void Logger::SetLevel(Logger::Level level) {

src/Util/Text.cpp

@@ -7,8 +7,6 @@
 #include "Util/Text.hpp"
 #include "Util/TransformUtils.hpp"
 
-#include "config.hpp"
-
 namespace Util {
 Text::Text(const std::string &font, int fontSize, const std::string &text,
            const Util::Color &color)