Init

Engine/BaseGame.cpp

@@ -0,0 +1,222 @@
+#include "base.h"
+#include <iostream>
+#include <algorithm>
+#include <chrono>
+#include "BaseGame.h"
+
+BaseGame::BaseGame(const Window& window)
+	: m_Window{ window }
+	, m_Viewport{ 0,0,window.width,window.height }
+	, m_pWindow{ nullptr }
+	, m_pContext{ nullptr }
+	, m_Initialized{ false }
+	, m_MaxElapsedSeconds{ 0.1f }
+{
+	InitializeGameEngine();
+}
+
+BaseGame::~BaseGame()
+{
+	CleanupGameEngine();
+}
+
+void BaseGame::InitializeGameEngine()
+{
+	// disable console close window button
+#ifdef _WIN32
+	HWND hwnd = GetConsoleWindow();
+	HMENU hmenu = GetSystemMenu(hwnd, FALSE);
+	EnableMenuItem(hmenu, SC_CLOSE, MF_GRAYED);
+#endif
+
+	// Initialize SDL
+	if (SDL_Init(SDL_INIT_VIDEO /*| SDL_INIT_AUDIO*/) < 0)
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling SDL_Init: " << SDL_GetError() << std::endl;
+		return;
+	}
+
+	// Use OpenGL 2.1
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
+
+	// Create window
+	m_pWindow = SDL_CreateWindow(
+		m_Window.title.c_str(),
+		SDL_WINDOWPOS_CENTERED,
+		SDL_WINDOWPOS_CENTERED,
+		int(m_Window.width),
+		int(m_Window.height),
+		SDL_WINDOW_OPENGL);
+	if (m_pWindow == nullptr)
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling SDL_CreateWindow: " << SDL_GetError() << std::endl;
+		return;
+	}
+
+	// Create OpenGL context 
+	m_pContext = SDL_GL_CreateContext(m_pWindow);
+	if (m_pContext == nullptr)
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling SDL_GL_CreateContext: " << SDL_GetError() << std::endl;
+		return;
+	}
+
+	// Set the swap interval for the current OpenGL context,
+	// synchronize it with the vertical retrace
+	if (m_Window.isVSyncOn)
+	{
+		if (SDL_GL_SetSwapInterval(1) < 0)
+		{
+			std::cerr << "BaseGame::Initialize( ), error when calling SDL_GL_SetSwapInterval: " << SDL_GetError() << std::endl;
+			return;
+		}
+	}
+	else
+	{
+		SDL_GL_SetSwapInterval(0);
+	}
+
+	// Set the Projection matrix to the identity matrix
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+
+	// Set up a two-dimensional orthographic viewing region.
+	glOrtho(0, m_Window.width, 0, m_Window.height, -1, 1); // y from bottom to top
+
+	// Set the viewport to the client window area
+	// The viewport is the rectangular region of the window where the image is drawn.
+	glViewport(0, 0, int(m_Window.width), int(m_Window.height));
+
+	// Set the Modelview matrix to the identity matrix
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+
+	// Enable color blending and use alpha blending
+	glEnable(GL_BLEND);
+	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+	// Initialize PNG loading
+	/*
+	int imgFlags = IMG_INIT_PNG;
+	if ( !( IMG_Init( imgFlags ) & imgFlags ) )
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling IMG_Init: " << IMG_GetError( ) << std::endl;
+		return;
+	}
+	*/
+
+	// Initialize SDL_ttf
+	if (TTF_Init() == -1)
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling TTF_Init: " << TTF_GetError() << std::endl;
+		return;
+	}
+
+	//Initialize SDL_mixer
+	
+	if (Mix_OpenAudio(44100, MIX_DEFAULT_FORMAT, 2, 2048) < 0)
+	{
+		std::cerr << "BaseGame::Initialize( ), error when calling Mix_OpenAudio: " << Mix_GetError() << std::endl;
+		return;
+	}
+	
+
+	m_Initialized = true;
+}
+
+void BaseGame::Run()
+{
+	if (!m_Initialized)
+	{
+		std::cerr << "BaseGame::Run( ), BaseGame not correctly initialized, unable to run the BaseGame\n";
+		std::cin.get();
+		return;
+	}
+
+	// Main loop flag
+	bool quit{ false };
+
+	// Set start time
+	std::chrono::steady_clock::time_point t1 = std::chrono::steady_clock::now();
+
+	//The event loop
+	SDL_Event e{};
+	while (!quit)
+	{
+		// Poll next event from queue
+		while (SDL_PollEvent(&e) != 0)
+		{
+			// Handle the polled event
+			switch (e.type)
+			{
+			case SDL_QUIT:
+				quit = true;
+				break;
+			case SDL_KEYDOWN:
+				this->ProcessKeyDownEvent(e.key);
+				break;
+			case SDL_KEYUP:
+				this->ProcessKeyUpEvent(e.key);
+				break;
+			case SDL_MOUSEMOTION:
+				e.motion.y = int(m_Window.height) - e.motion.y;
+				this->ProcessMouseMotionEvent(e.motion);
+				break;
+			case SDL_MOUSEBUTTONDOWN:
+				e.button.y = int(m_Window.height) - e.button.y;
+				this->ProcessMouseDownEvent(e.button);
+				break;
+			case SDL_MOUSEBUTTONUP:
+				e.button.y = int(m_Window.height) - e.button.y;
+				this->ProcessMouseUpEvent(e.button);
+				break;
+			}
+		}
+
+		if (!quit)
+		{
+			// Get current time
+			std::chrono::steady_clock::time_point t2 = std::chrono::steady_clock::now();
+
+			// Calculate elapsed time
+			float elapsedSeconds = std::chrono::duration<float>(t2 - t1).count();
+
+			// Update current time
+			t1 = t2;
+
+			// Prevent jumps in time caused by break points
+			elapsedSeconds = std::min(elapsedSeconds, m_MaxElapsedSeconds);
+
+			// Call the BaseGame object 's Update function, using time in seconds (!)
+			this->Update(elapsedSeconds);
+
+			// Draw in the back buffer
+			this->Draw();
+
+			// Update screen: swap back and front buffer
+			SDL_GL_SwapWindow(m_pWindow);
+		}
+	}
+}
+
+void BaseGame::CleanupGameEngine()
+{
+	SDL_GL_DeleteContext(m_pContext);
+
+	SDL_DestroyWindow(m_pWindow);
+	m_pWindow = nullptr;
+
+	//Quit SDL subsystems
+	Mix_Quit();
+	TTF_Quit();
+	SDL_Quit();
+
+	// enable console close window button
+#ifdef _WIN32
+	HWND hwnd = GetConsoleWindow();
+	HMENU hmenu = GetSystemMenu(hwnd, FALSE);
+	EnableMenuItem(hmenu, SC_CLOSE, MF_ENABLED);
+#endif
+
+}