light/Engine/src/Platform/GraphicsAPI/OpenGL/glUserInterface.cpp

#include "ltpch.h"
#include "glUserInterface.h"

#include <imgui.h>
#include <imgui_impl_glfw.h>
#include <imgui_impl_opengl3.h>

#include <GLFW/glfw3.h>

namespace Light {

	glUserInterface::glUserInterface(GLFWwindow* windowHandle)
		: m_WindowHandle(windowHandle)
	{
		// create context
		IMGUI_CHECKVERSION();
		ImGui::CreateContext();

		// configure  io
		ImGuiIO& io = ImGui::GetIO();
		io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
		io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
		io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;

		io.ConfigFlags |= ImGuiBackendFlags_PlatformHasViewports;
		io.ConfigFlags |= ImGuiBackendFlags_RendererHasViewports;

		// #todo: handle this in a better way
		if (std::filesystem::exists("user_gui_layout.ini"))
			io.IniFilename = "user_gui_layout.ini";
		else
			io.IniFilename = "default_gui_layout.ini";

		// style color
		ImGui::StyleColorsDark();

		// init
		ImGui_ImplGlfw_InitForOpenGL(windowHandle, false);
		ImGui_ImplOpenGL3_Init();
	}

	glUserInterface::~glUserInterface()
	{
		// #todo: handle this in a better way
		ImGuiIO& io = ImGui::GetIO();

		if (io.IniFilename == "default_gui_layout.ini")
			io.IniFilename = "user_gui_layout.ini";

		ImGui_ImplOpenGL3_Shutdown();
		ImGui_ImplGlfw_Shutdown();
		ImGui::DestroyContext();
	}

	void glUserInterface::Begin()
	{
		ImGui_ImplOpenGL3_NewFrame();
		ImGui_ImplGlfw_NewFrame();
		ImGui::NewFrame();

		//** #TEMP_IMGUI_DEMO_TEMP# **//
		ImGui::ShowDemoWindow();
	}

	void glUserInterface::End()
	{
		ImGui::Render();
		ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

		ImGui::UpdatePlatformWindows();
		ImGui::RenderPlatformWindowsDefault();
		glfwMakeContextCurrent(m_WindowHandle);
	}

	void glUserInterface::LogDebugData()
	{
		// #todo: improve
		LT_ENGINE_INFO("________________________________________");
		LT_ENGINE_INFO("UserInterface::");
		LT_ENGINE_INFO("       API    : ImGui");
		LT_ENGINE_INFO("       Version: {}", ImGui::GetVersion());
		LT_ENGINE_INFO("  GraphicsAPI : OpenGL");
		LT_ENGINE_INFO("________________________________________");
	}

}