Tower-Defense2/src/td/input/Display.cpp

#include <td/input/Display.h>

#include <GL/glew.h>
#include <SDL3/SDL.h>
#include <imgui.h>
#include <imgui_impl_opengl3.h>
#include <imgui_impl_sdl3.h>

#include <td/misc/Format.h>
#include <td/misc/Log.h>

namespace td {

Display::Display(int a_Width, int a_Height, const std::string& a_Title) :
	m_LastWidth(0), m_LastHeight(0), m_AspectRatio(1), m_ShouldClose(false) {

	m_Window = SDL_CreateWindow(a_Title.c_str(), a_Width, a_Height, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);

	m_LastWidth = a_Width;
	m_LastHeight = a_Height;
	m_AspectRatio = (float)m_LastWidth / m_LastHeight;

	// Prepare and create context
#ifdef __ANDROID__
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
#else
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
#endif
	SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 5);
	SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 6);
	SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 5);
	SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 0);

	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);

	m_GLContext = SDL_GL_CreateContext(m_Window);

	if (!m_GLContext) {
		utils::LOGE(utils::Format("Could not create context! SDL error: %s", SDL_GetError()));
	}

	int major, minor, mask;
	int r, g, b, a, depth;
	SDL_GL_GetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, &mask);
	SDL_GL_GetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, &major);
	SDL_GL_GetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, &minor);

	SDL_GL_GetAttribute(SDL_GL_RED_SIZE, &r);
	SDL_GL_GetAttribute(SDL_GL_GREEN_SIZE, &g);
	SDL_GL_GetAttribute(SDL_GL_BLUE_SIZE, &b);
	SDL_GL_GetAttribute(SDL_GL_ALPHA_SIZE, &a);

	SDL_GL_GetAttribute(SDL_GL_DEPTH_SIZE, &depth);

	const char* mask_desc;

	if (mask & SDL_GL_CONTEXT_PROFILE_CORE) {
		mask_desc = "core";
	} else if (mask & SDL_GL_CONTEXT_PROFILE_COMPATIBILITY) {
		mask_desc = "compatibility";
	} else if (mask & SDL_GL_CONTEXT_PROFILE_ES) {
		mask_desc = "es";
	} else {
		mask_desc = "?";
	}

	utils::LOG(utils::Format(
		"GL Context : %i.%i %s, Color : R:%i G:%i B:%i A:%i, Depth bits : %i", major, minor, mask_desc, r, g, b, a, depth));

	SDL_GL_MakeCurrent(m_Window, m_GLContext);

	GLenum error = glewInit();
	if (error) {
		utils::LOGE(utils::Format("Error initializing glew : %s", glewGetErrorString(error)));
	}

	// WindowResizeEvent(WindowWidth, WindowHeight);

	// vsync
	SDL_GL_SetSwapInterval(1);

	// Setup Dear ImGui context
	IMGUI_CHECKVERSION();
	ImGui::CreateContext();
	ImGuiIO& io = ImGui::GetIO();
	(void)io;
	io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
	io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;   // Enable Gamepad Controls

	// Setup Dear ImGui style
	ImGui::StyleColorsDark();
	// ImGui::StyleColorsLight();

	// Setup scaling
	float main_scale = SDL_GetDisplayContentScale(SDL_GetPrimaryDisplay());
	// ImGuiStyle& style = ImGui::GetStyle();
	// style.ScaleAllSizes(main_scale);  // Bake a fixed style scale. (until we have a solution for dynamic style scaling, changing this
	// 								  // requires resetting Style + calling this again)
	// style.FontSizeBase = 13 * main_scale;  // Set initial font scale. (using io.ConfigDpiScaleFonts=true makes this unnecessary. We leave
	// 								  // both here for documentation purpose)


	ImFontConfig cfg;
	cfg.SizePixels = 13 * main_scale * 2;
	io.Fonts->AddFontDefault(&cfg);

	// Setup Platform/Renderer backends
	ImGui_ImplSDL3_InitForOpenGL(m_Window, m_GLContext);
	ImGui_ImplOpenGL3_Init("#version 330");
}


void Display::PollEvents() {
	SDL_Event event;
	while (SDL_PollEvent(&event)) {
		switch (event.type) {
			case SDL_EVENT_QUIT:
			case SDL_EVENT_WINDOW_CLOSE_REQUESTED: {
				m_ShouldClose = true;
				break;
			}

			case SDL_EVENT_WINDOW_RESIZED: {
				m_LastWidth = event.window.data1;
				m_LastHeight = event.window.data2;
				m_AspectRatio = (float)m_LastWidth / m_LastHeight;
				OnAspectRatioChange(m_AspectRatio);
				break;
			}

			case SDL_EVENT_KEY_DOWN: {
				if(!event.key.repeat)
					OnKeyDown(event.key.key);
				break;
			}

			default:
				break;
		}
		ImGui_ImplSDL3_ProcessEvent(&event);
	}
	// Start the Dear ImGui frame
	ImGui_ImplOpenGL3_NewFrame();
	ImGui_ImplSDL3_NewFrame();
	ImGui::NewFrame();
}

void Display::Update() {
	ImGui::Render();
	ImGuiIO& io = ImGui::GetIO();
	glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
	// glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
	ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
	SDL_GL_SwapWindow(m_Window);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
}


Display::~Display() {
	ImGui_ImplOpenGL3_Shutdown();
	ImGui_ImplSDL3_Shutdown();
	ImGui::DestroyContext();
	SDL_GL_DestroyContext(m_GLContext);
	SDL_DestroyWindow(m_Window);
	SDL_Quit();
}

}  // namespace td