diff --git a/include/uui/component.hpp b/include/uui/component.hpp
index a9ad0bb..ef91c34 100644
--- a/include/uui/component.hpp
+++ b/include/uui/component.hpp
@@ -14,22 +14,30 @@ class Component
 public:
 	virtual void set_background_color(float r, float g, float b, float a = 1.0f) = 0;
 
+	ComponentType type() { return _type; }
+	uui::position_t x() { return _position_x; }
+	uui::position_t y() { return _position_y; }
+	uui::size_t width() { return _width; }
+	uui::size_t height() { return _height; }
+
 protected:
-	std::shared_ptr<Window> window;
-	std::size_t window_index;
-	std::shared_ptr<Container> parent;
-	std::size_t parent_index;
+	ComponentType _type = ComponentType::UNASSIGNED;
 
-	uui::position_t position_x;
-	uui::position_t position_y;
-	uui::size_t size_width;
-	uui::size_t size_height;
+	std::shared_ptr<Window> _window;
+	std::size_t _window_index;
+	std::shared_ptr<Container> _parent;
+	std::size_t _parent_index;
 
-	bool coord_all_relative;
+	uui::position_t _position_x;
+	uui::position_t _position_y;
+	uui::size_t _width;
+	uui::size_t _height;
 
-	std::array<float, 4> background_color;
+	bool _coord_all_relative;
 
-	bool initialized;
+	std::array<float, 4> _background_color;
+
+	bool _initialized = false;
 
 	virtual void render() = 0;
 };
diff --git a/include/uui/container.hpp b/include/uui/container.hpp
index 43d1b24..782ff97 100644
--- a/include/uui/container.hpp
+++ b/include/uui/container.hpp
@@ -1,36 +1,12 @@
 #pragma once
 
-#include <cstdlib>
-
-#include <iostream>
-#include <memory>
-#include <vector>
-
+#include "uui/component.hpp"
+#include "uui/container_interface.hpp"
 #include "uui/types.hpp"
 
 namespace uui
 {
-class Component;
-class GlComponent;
-class Container
-{
-	friend class GlComponent;
-
-public:
-	enum Type
-	{
-		WINDOW,
-		FLEX,
-		STACK
-	};
-
-	Type type;
-
-protected:
-	virtual std::size_t push_child(std::shared_ptr<Component> child) = 0;
-	virtual std::shared_ptr<Component> get_child(std::size_t index) const = 0;
-	virtual void remove_child(std::size_t index) = 0;
-	virtual std::tuple<int, int> get_child_position(const std::size_t child_index [[maybe_unused]]) const = 0;
-};
+class Container: virtual public Component, virtual public ContainerInterface
+{};
 
 } // namespace uui
diff --git a/include/uui/container_interface.hpp b/include/uui/container_interface.hpp
new file mode 100644
index 0000000..287e918
--- /dev/null
+++ b/include/uui/container_interface.hpp
@@ -0,0 +1,21 @@
+#pragma once
+
+#include <memory>
+#include <tuple>
+
+#include "uui/types.hpp"
+
+namespace uui
+{
+class Component;
+class ContainerInterface
+{
+public:
+	virtual std::tuple<int, int> get_child_position(const std::size_t child_index [[maybe_unused]]) const = 0;
+protected:
+	virtual std::size_t push_child(std::shared_ptr<Component> child) = 0;
+	virtual std::shared_ptr<Component> get_child(std::size_t index) const = 0;
+	virtual void remove_child(std::size_t index) = 0;
+};
+
+} // namespace uui
diff --git a/include/uui/font_manager.hpp b/include/uui/font_manager.hpp
index e7126d6..52da172 100644
--- a/include/uui/font_manager.hpp
+++ b/include/uui/font_manager.hpp
@@ -51,6 +51,6 @@ protected:
 	bool initialized;
 
 	FT_Library ft;
-	virtual const Font& init_font(const std::string& font_path, std::size_t font_size) = 0;
+	virtual const Font& init_font(const std::string& font_path, unsigned int font_size) = 0;
 };
 } // namespace uui
diff --git a/include/uui/label.hpp b/include/uui/label.hpp
index 2de7c22..6b4f42a 100644
--- a/include/uui/label.hpp
+++ b/include/uui/label.hpp
@@ -20,3 +20,4 @@ protected:
 };
 
 } // namespace uui
+
diff --git a/include/uui/opengl/component.hpp b/include/uui/opengl/component.hpp
index 441e322..6ecaa99 100644
--- a/include/uui/opengl/component.hpp
+++ b/include/uui/opengl/component.hpp
@@ -3,19 +3,18 @@
 #include <array>
 #include <memory>
 
-#include "graphic_context.hpp"
-#include "uui/container.hpp"
-#include "uui/opengl/component.hpp"
+#include "uui/component.hpp"
+#include "uui/opengl/graphic_context.hpp"
 #include "uui/opengl/window.hpp"
 #include "uui/types.hpp"
 
 namespace uui
 {
+class GlContainer;
 class GlFlex;
 class GlStack;
 class GlComponent: public std::enable_shared_from_this<GlComponent>, virtual public Component
 {
-	friend class Container;
 	friend class GlContainer;
 	friend class GlWindow;
 	friend class GlFlex;
@@ -36,7 +35,7 @@ protected:
 		std::shared_ptr<GlWindow> window, std::size_t window_index, std::shared_ptr<GlContainer> parent,
 		std::size_t parent_index, const ComponentParams& params);
 	GlComponent(std::shared_ptr<GlWindow> window, std::size_t window_index, const ComponentParams& params):
-		GlComponent(window, window_index, std::static_pointer_cast<GlContainer>(window), window_index, params)
+		GlComponent(window, window_index, nullptr, 0, params)
 	{}
 	GlComponent(const GlComponent&) = delete;
 	GlComponent(GlComponent&&) = default;
diff --git a/include/uui/opengl/container.hpp b/include/uui/opengl/container.hpp
index ace8ae1..8deaf6d 100644
--- a/include/uui/opengl/container.hpp
+++ b/include/uui/opengl/container.hpp
@@ -6,28 +6,13 @@
 #include <memory>
 #include <vector>
 
-#include "uui/component.hpp"
 #include "uui/container.hpp"
+#include "uui/opengl/component.hpp"
+#include "uui/opengl/container_interface.hpp"
 
 namespace uui
 {
-class GlContainer: virtual public Container
-{
-protected:
-	GlContainer() = default;
-	GlContainer(const GlContainer&) = default;
-	GlContainer(GlContainer&&) = default;
-
-	virtual std::size_t push_child(std::shared_ptr<Component> child [[maybe_unused]]) final;
-	std::size_t push_child(std::shared_ptr<GlComponent> child);
-	std::shared_ptr<Component> get_child(std::size_t index) const final;
-	virtual void remove_child(std::size_t index) final;
-	virtual std::tuple<int, int> get_child_position(const std::size_t child_index [[maybe_unused]]) const override;
-
-	std::vector<std::shared_ptr<GlComponent>> components;
-
-public:
-	~GlContainer();
-};
+class GlContainer: virtual public Container, virtual public GlContainerInterface
+{};
 
 } // namespace uui
diff --git a/include/uui/opengl/container_interface.hpp b/include/uui/opengl/container_interface.hpp
new file mode 100644
index 0000000..e068ffa
--- /dev/null
+++ b/include/uui/opengl/container_interface.hpp
@@ -0,0 +1,28 @@
+#pragma once
+
+#include <memory>
+#include <tuple>
+
+#include "uui/component.hpp"
+#include "uui/container_interface.hpp"
+#include "uui/types.hpp"
+
+namespace uui
+{
+class GlComponent;
+class GlContainerInterface: virtual public ContainerInterface
+{
+public:
+	virtual std::tuple<int, int> get_child_position(const std::size_t child_index [[maybe_unused]]) const override;
+
+protected:
+	virtual std::size_t push_child(std::shared_ptr<Component> child) final;
+	std::size_t push_child(std::shared_ptr<GlComponent> child);
+	virtual std::shared_ptr<Component> get_child(std::size_t index) const final;
+	virtual void remove_child(std::size_t index) final;
+
+	virtual ~GlContainerInterface();
+
+	std::vector<std::shared_ptr<GlComponent>> components;
+};
+} // namespace uui
diff --git a/include/uui/opengl/flex.hpp b/include/uui/opengl/flex.hpp
index e0bcdc5..975d30c 100644
--- a/include/uui/opengl/flex.hpp
+++ b/include/uui/opengl/flex.hpp
@@ -20,7 +20,7 @@ protected:
 		std::shared_ptr<GlWindow> window, std::size_t window_index, std::shared_ptr<GlContainer> parent,
 		std::size_t parent_index, const StackParams& params);
 	GlFlex(std::shared_ptr<GlWindow> window, std::size_t window_index, const StackParams& params):
-		GlFlex(window, window_index, window, window_index, params)
+		GlFlex(window, window_index, nullptr, 0, params)
 	{}
 
 	std::tuple<int, int> get_child_position(const std::size_t child_index) const override;
diff --git a/include/uui/opengl/font_manager.hpp b/include/uui/opengl/font_manager.hpp
index 19d1ab7..e797f1b 100644
--- a/include/uui/opengl/font_manager.hpp
+++ b/include/uui/opengl/font_manager.hpp
@@ -5,9 +5,6 @@
 #include <tuple>
 #include <vector>
 
-#include <ft2build.h>
-#include FT_FREETYPE_H
-
 #include "uui/font_manager.hpp"
 #include "uui/opengl/graphic_context.hpp"
 
@@ -34,6 +31,6 @@ private:
 
 	void init();
 	void deinit();
-	const Font& init_font(const std::string& font_path, std::size_t font_size);
+	const Font& init_font(const std::string& font_path, unsigned int font_size);
 };
 } // namespace uui
diff --git a/include/uui/opengl/graphic_context.hpp b/include/uui/opengl/graphic_context.hpp
index 5837abc..62635a7 100644
--- a/include/uui/opengl/graphic_context.hpp
+++ b/include/uui/opengl/graphic_context.hpp
@@ -12,7 +12,7 @@
 #include <glm/gtc/type_ptr.hpp>
 // clang-format off
 
-namespace Config
+namespace GlConfig
 {
 	constexpr unsigned int FONT_TEXTURE_UNIT = GL_TEXTURE0;
 }
diff --git a/include/uui/opengl/label.hpp b/include/uui/opengl/label.hpp
index 4570717..266b615 100644
--- a/include/uui/opengl/label.hpp
+++ b/include/uui/opengl/label.hpp
@@ -6,6 +6,7 @@
 #include "uui/label.hpp"
 #include "uui/opengl/component.hpp"
 #include "uui/opengl/container.hpp"
+#include "uui/opengl/window.hpp"
 
 namespace uui
 {
@@ -28,7 +29,7 @@ protected:
 		std::shared_ptr<GlWindow> window, std::size_t window_index, std::shared_ptr<GlContainer> parent,
 		std::size_t parent_index, const LabelParams& params);
 	GlLabel(std::shared_ptr<GlWindow> window, std::size_t window_index, const LabelParams& params):
-		GlLabel(window, window_index, window, window_index, params)
+		GlLabel(window, window_index, nullptr, 0, params)
 	{}
 
 	void render() final;
diff --git a/include/uui/opengl/stack.hpp b/include/uui/opengl/stack.hpp
index b625314..52310c4 100644
--- a/include/uui/opengl/stack.hpp
+++ b/include/uui/opengl/stack.hpp
@@ -23,7 +23,7 @@ protected:
 		std::shared_ptr<GlWindow> window, std::size_t window_index, std::shared_ptr<GlContainer> parent,
 		std::size_t parent_index, const StackParams& params);
 	GlStack(std::shared_ptr<GlWindow> window, std::size_t window_index, const StackParams& params):
-		GlStack(window, window_index, window, window_index, params)
+		GlStack(window, window_index, nullptr, 0, params)
 	{}
 
 	std::tuple<int, int> get_child_position(const std::size_t child_index) const override;
diff --git a/include/uui/opengl/window.hpp b/include/uui/opengl/window.hpp
index 67543da..6a5ab32 100644
--- a/include/uui/opengl/window.hpp
+++ b/include/uui/opengl/window.hpp
@@ -1,7 +1,7 @@
 #pragma once
 
 #include "uui/opengl/application.hpp"
-#include "uui/opengl/container.hpp"
+#include "uui/opengl/container_interface.hpp"
 #include "uui/opengl/font_manager.hpp"
 #include "uui/types.hpp"
 #include "uui/window.hpp"
@@ -13,7 +13,10 @@ class GlContainer;
 class GlFlex;
 class GlLabel;
 class GlStack;
-class GlWindow final: public std::enable_shared_from_this<GlWindow>, virtual public Window, virtual public GlContainer
+class GlWindow:
+	public std::enable_shared_from_this<GlWindow>,
+	virtual public Window,
+	virtual public GlContainerInterface
 {
 	friend class GlApplication;
 	friend class GlComponent;
@@ -48,5 +51,6 @@ protected:
 	static void glfw_resize_callback(GLFWwindow* window, int width, int height);
 	static void glfw_iconify_callback(GLFWwindow* window, int iconified);
 	static void glfw_key_callback(GLFWwindow* window, int key, int scancode, int action, int mods);
+	// static void glfw_mouse_button_callback(GLFWwindow* window, int button, int action, int mods);
 };
 } // namespace uui
diff --git a/include/uui/types.hpp b/include/uui/types.hpp
index fae7b2f..d329768 100644
--- a/include/uui/types.hpp
+++ b/include/uui/types.hpp
@@ -6,12 +6,28 @@
 
 namespace uui
 {
+namespace Config
+{
+constexpr int MOUSE_GRID_WIDTH = 20;
+constexpr int MOUSE_GRID_HEIGHT = 20;
+}; // namespace Config
+
 template<typename T> using InitFunction = const std::function<void(T&)>&;
 typedef std::variant<int, float> position_t;
 typedef std::variant<int, float> size_t;
 typedef std::tuple<float, float, float, float> color_t;
 
-enum Direction
+enum class ComponentType
+{
+	UNASSIGNED,
+	COMPONENT,
+	LABEL,
+	FLEX,
+	STACK,
+	WINDOW
+};
+
+enum class Direction
 {
 	HORIZONTAL,
 	VERTICAL
diff --git a/include/uui/window.hpp b/include/uui/window.hpp
index 936b273..16abe65 100644
--- a/include/uui/window.hpp
+++ b/include/uui/window.hpp
@@ -1,10 +1,11 @@
 #pragma once
 
+#include <array>
 #include <memory>
 #include <string>
 
 #include "uui/application.hpp"
-#include "uui/container.hpp"
+#include "uui/container_interface.hpp"
 #include "uui/font_manager.hpp"
 #include "uui/types.hpp"
 
@@ -14,13 +15,11 @@ class Component;
 class Label;
 class Flex;
 class Stack;
-class Window: virtual public Container
+class Window: virtual public ContainerInterface
 {
 	friend class Component;
 
 public:
-	std::string title;
-
 	std::shared_ptr<FontManager> font_manager;
 
 	virtual void create_component(const ComponentParams& params, InitFunction<Component> init) = 0;
@@ -28,19 +27,26 @@ public:
 	virtual void create_flex(const StackParams& params, InitFunction<Flex> init) = 0;
 	virtual void create_stack(const StackParams& params, InitFunction<Stack> init) = 0;
 
+	const std::string& title() { return _title; }
 	int width() { return _width; };
 	int height() { return _height; };
 
 protected:
+	ComponentType _type = ComponentType::UNASSIGNED;
+
 	std::shared_ptr<Application> _app;
 	bool _initialized;
 
+	std::string _title;
 	int _width;
 	int _height;
 	bool _render_needed;
 	bool _resize_needed;
 	bool _iconified;
 
+	std::array<std::array<std::vector<std::shared_ptr<Component>>, Config::MOUSE_GRID_HEIGHT>, Config::MOUSE_GRID_WIDTH>
+		_grid_click;
+
 	virtual void render() = 0;
 };
 } // namespace uui
diff --git a/src/uui/opengl/application.cpp b/src/uui/opengl/application.cpp
index 1fc5879..ab964f2 100644
--- a/src/uui/opengl/application.cpp
+++ b/src/uui/opengl/application.cpp
@@ -94,7 +94,7 @@ void uui::GlApplication::run()
 					glfwSwapInterval(1);
 				}
 				if constexpr(debug_mode)
-					std::cout << "\nGlApplication closing GlWindow : " << window->title << std::endl;
+					std::cout << "\nGlApplication closing GlWindow : " << window->title() << std::endl;
 				window->deinit();
 				windows.erase(it);
 				it -= 1;
diff --git a/src/uui/opengl/component.cpp b/src/uui/opengl/component.cpp
index 3857260..35c1e10 100644
--- a/src/uui/opengl/component.cpp
+++ b/src/uui/opengl/component.cpp
@@ -13,44 +13,44 @@ uui::GlComponent::GlComponent(
 	if constexpr(uui::Application::debug_mode)
 		std::cout << "Creating a GlComponent " << parent_index << std::endl;
 
+	_type = ComponentType::COMPONENT;
+
 	gl_window = window;
-	this->window = std::static_pointer_cast<uui::Window>(window);
+	this->_window = std::static_pointer_cast<uui::Window>(window);
+	this->_window_index = window_index;
+	this->_parent = std::static_pointer_cast<uui::Container>(parent);
+	this->_parent_index = parent_index;
 
-	this->window_index = window_index;
-	this->parent = parent;
-	this->parent_index = parent_index;
-	this->parent_index = parent_index;
+	_initialized = false;
 
-	initialized = false;
+	_position_x = params.x;
+	_position_y = params.y;
+	_width = params.width;
+	_height = params.height;
 
-	position_x = params.x;
-	position_y = params.y;
-	size_width = params.width;
-	size_height = params.height;
-
-	coord_all_relative = true;
+	_coord_all_relative = true;
 	auto parse_coords = [&](position_t& value) {
 		if(value.index() == 0)
 		{
 			if(std::get<0>(value) == 0)
 				value = 0.0f;
 			else
-				coord_all_relative = false;
+				_coord_all_relative = false;
 		}
 	};
-	parse_coords(position_x);
-	parse_coords(position_y);
-	parse_coords(size_width);
-	parse_coords(size_height);
+	parse_coords(_position_x);
+	parse_coords(_position_y);
+	parse_coords(_width);
+	parse_coords(_height);
 
-	background_color = {0.0f, 0.0f, 0.0f, 0.0f};
+	_background_color = {0.0f, 0.0f, 0.0f, 0.0f};
 }
 
 uui::GlComponent::~GlComponent()
 {
 	if constexpr(uui::GlApplication::debug_mode)
-		std::cout << "Destructor GlComponent " << parent_index << std::endl;
-	if(initialized)
+		std::cout << "Destructor GlComponent " << _parent_index << std::endl;
+	if(_initialized)
 		deinit();
 	// if(parent != window)
 	// 	parent->remove_child(0); // TODO
@@ -58,7 +58,7 @@ uui::GlComponent::~GlComponent()
 
 void uui::GlComponent::set_background_color(float r, float g, float b, float a /*=0.0f*/)
 {
-	background_color = {r, g, b, a};
+	_background_color = {r, g, b, a};
 	glBindVertexArray(gl_vao);
 	set_vbo_data();
 	glBindVertexArray(0); // Optional : for safety
@@ -66,7 +66,7 @@ void uui::GlComponent::set_background_color(float r, float g, float b, float a /
 
 void uui::GlComponent::init()
 {
-	if(initialized)
+	if(_initialized)
 		throw std::runtime_error("GlComponent error : calling init while already initialized");
 
 	glGenVertexArrays(1, &gl_vao);
@@ -94,23 +94,22 @@ void uui::GlComponent::init()
 	glBindBuffer(GL_ARRAY_BUFFER, 0);
 	glBindVertexArray(0);
 
-	initialized = true;
+	_initialized = true;
 }
 
 void uui::GlComponent::set_vbo_data()
 {
-	float vert_x = position_x.index() == 1
-		? std::get<1>(position_x)
-		: static_cast<float>(std::get<0>(position_x)) / static_cast<float>(window->width());
-	float vert_y = position_y.index() == 1
-		? std::get<1>(position_y)
-		: static_cast<float>(std::get<0>(position_y)) / static_cast<float>(window->height());
-	float vert_w = size_width.index() == 1
-		? std::get<1>(size_width)
-		: static_cast<float>(std::get<0>(size_width)) / static_cast<float>(window->width());
-	float vert_h = size_height.index() == 1
-		? std::get<1>(size_height)
-		: static_cast<float>(std::get<0>(size_height)) / static_cast<float>(window->height());
+	float vert_x = _position_x.index() == 1
+		? std::get<1>(_position_x)
+		: static_cast<float>(std::get<0>(_position_x)) / static_cast<float>(_window->width());
+	float vert_y = _position_y.index() == 1
+		? std::get<1>(_position_y)
+		: static_cast<float>(std::get<0>(_position_y)) / static_cast<float>(_window->height());
+	float vert_w = _width.index() == 1 ? std::get<1>(_width)
+									   : static_cast<float>(std::get<0>(_width)) / static_cast<float>(_window->width());
+	float vert_h = _height.index() == 1
+		? std::get<1>(_height)
+		: static_cast<float>(std::get<0>(_height)) / static_cast<float>(_window->height());
 	float x_min = (2.0f * vert_x) - 1.0f;
 	float x_max = x_min + (2.0f * vert_w);
 	float y_min = (-2.0f * vert_y) + 1.0f;
@@ -118,10 +117,10 @@ void uui::GlComponent::set_vbo_data()
 	// clang-format off
 	float vertices[] =
 	{
-		x_max, y_min, background_color[0], background_color[1], background_color[2], background_color[3],  // top right
-		x_max, y_max, background_color[0], background_color[1], background_color[2], background_color[3],  // bottom right
-		x_min, y_max, background_color[0], background_color[1], background_color[2], background_color[3],  // bottom left
-		x_min, y_min, background_color[0], background_color[1], background_color[2], background_color[3]   // top left
+		x_max, y_min, _background_color[0], _background_color[1], _background_color[2], _background_color[3],  // top right
+		x_max, y_max, _background_color[0], _background_color[1], _background_color[2], _background_color[3],  // bottom right
+		x_min, y_max, _background_color[0], _background_color[1], _background_color[2], _background_color[3],  // bottom left
+		x_min, y_min, _background_color[0], _background_color[1], _background_color[2], _background_color[3]   // top left
 	};
 	// clang-format on
 	glBindBuffer(GL_ARRAY_BUFFER, gl_vbo);
@@ -150,18 +149,18 @@ void uui::GlComponent::set_vbo_data()
 void uui::GlComponent::deinit()
 {
 	if constexpr(uui::GlApplication::debug_mode)
-		std::cout << "Deinit GlComponent " << parent_index << std::endl;
+		std::cout << "Deinit GlComponent " << _parent_index << std::endl;
 
-	if(!initialized)
+	if(!_initialized)
 		throw std::runtime_error("GlComponent error : calling deinit while not initialized");
 
 	glDeleteVertexArrays(1, &gl_vao);
 	glDeleteBuffers(1, &gl_vbo);
 	glDeleteBuffers(1, &gl_ebo);
 
-	window = nullptr;
-	parent = nullptr;
-	initialized = false;
+	_window = nullptr;
+	_parent = nullptr;
+	_initialized = false;
 }
 
 void uui::GlComponent::render()
@@ -172,11 +171,12 @@ void uui::GlComponent::render()
 
 void uui::GlComponent::on_resize()
 {
-	bool is_in_stack = parent->type == GlContainer::Type::FLEX || parent->type == GlContainer::Type::STACK;
-	if(!coord_all_relative || is_in_stack)
+	bool is_in_stack =
+		_parent != nullptr && (_parent->type() == ComponentType::FLEX || _parent->type() == ComponentType::STACK);
+	if(!_coord_all_relative || is_in_stack)
 	{
 		if(is_in_stack)
-			std::tie(position_x, position_y) = parent->get_child_position(parent_index);
+			std::tie(_position_x, _position_y) = _parent->get_child_position(_parent_index);
 		glBindVertexArray(gl_vao);
 		set_vbo_data();
 		glBindVertexArray(0); // Optional : for safety
diff --git a/src/uui/opengl/container.cpp b/src/uui/opengl/container.cpp
deleted file mode 100644
index 4d45bf0..0000000
--- a/src/uui/opengl/container.cpp
+++ /dev/null
@@ -1,37 +0,0 @@
-#include "uui/opengl/container.hpp"
-
-#include "uui/opengl/component.hpp"
-
-std::size_t uui::GlContainer::push_child(std::shared_ptr<uui::Component> child [[maybe_unused]])
-{
-	throw std::runtime_error("GlContainer error : should only push GlComponent child, not Component");
-}
-
-std::size_t uui::GlContainer::push_child(std::shared_ptr<uui::GlComponent> child)
-{
-	components.push_back(child);
-	// components.push_back(std::static_pointer_cast<uui::Component>(child));
-	return components.size() - 1;
-}
-
-std::shared_ptr<uui::Component> uui::GlContainer::get_child(std::size_t index) const
-{
-	return components.at(index);
-}
-
-void uui::GlContainer::remove_child(std::size_t index)
-{
-	components.at(index) = nullptr;
-};
-
-std::tuple<int, int> uui::GlContainer::get_child_position(const std::size_t child_index [[maybe_unused]]) const
-{
-	return {0, 0};
-}
-
-uui::GlContainer::~GlContainer()
-{
-	if constexpr(uui::Application::debug_mode)
-		std::cout << "Destroying GlContainer" << std::endl;
-	components.clear();
-}
diff --git a/src/uui/opengl/container_interface.cpp b/src/uui/opengl/container_interface.cpp
new file mode 100644
index 0000000..2abe608
--- /dev/null
+++ b/src/uui/opengl/container_interface.cpp
@@ -0,0 +1,38 @@
+#include "uui/opengl/container_interface.hpp"
+
+#include <iostream>
+
+#include "uui/opengl/component.hpp"
+
+std::size_t uui::GlContainerInterface::push_child(std::shared_ptr<uui::Component> child [[maybe_unused]])
+{
+	throw std::runtime_error("GlContainerInterface error : should only push GlComponent child, not Component");
+}
+
+std::size_t uui::GlContainerInterface::push_child(std::shared_ptr<uui::GlComponent> child)
+{
+	components.push_back(child);
+	return components.size() - 1;
+}
+
+std::shared_ptr<uui::Component> uui::GlContainerInterface::get_child(std::size_t index) const
+{
+	return components.at(index);
+}
+
+void uui::GlContainerInterface::remove_child(std::size_t index)
+{
+	components.at(index) = nullptr;
+};
+
+std::tuple<int, int> uui::GlContainerInterface::get_child_position(const std::size_t child_index [[maybe_unused]]) const
+{
+	return {0, 0};
+}
+
+uui::GlContainerInterface::~GlContainerInterface()
+{
+	if constexpr(uui::Application::debug_mode)
+		std::cout << "Destroying GlContainerInterface" << std::endl;
+	components.clear();
+}
diff --git a/src/uui/opengl/flex.cpp b/src/uui/opengl/flex.cpp
index bbfd4f8..e38b6e0 100644
--- a/src/uui/opengl/flex.cpp
+++ b/src/uui/opengl/flex.cpp
@@ -13,18 +13,19 @@ uui::GlFlex::GlFlex(
 	if constexpr(uui::GlApplication::debug_mode)
 		std::cout << "Creating a GlFlex " << parent_index << std::endl;
 
-	type = Type::FLEX;
-	coord_all_relative = false;
+	_type = ComponentType::FLEX;
+
+	_coord_all_relative = false;
 }
 
 std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_index) const
 {
-	const int initial_x = position_x.index() == 0
-		? std::get<0>(position_x)
-		: static_cast<int>(std::get<1>(position_x) * static_cast<float>(window->width()));
-	const int initial_y = position_y.index() == 0
-		? std::get<0>(position_y)
-		: static_cast<int>(std::get<1>(position_y) * static_cast<float>(window->height()));
+	const int initial_x = _position_x.index() == 0
+		? std::get<0>(_position_x)
+		: static_cast<int>(std::get<1>(_position_x) * static_cast<float>(_window->width()));
+	const int initial_y = _position_y.index() == 0
+		? std::get<0>(_position_y)
+		: static_cast<int>(std::get<1>(_position_y) * static_cast<float>(_window->height()));
 
 	if(child_index == 0)
 		return {initial_x, initial_y};
@@ -37,14 +38,14 @@ std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_ind
 		if(components[index] != nullptr)
 		{
 			auto& component = components[index];
-			if(component->size_width.index() == 1)
-				width = static_cast<int>(std::get<1>(component->size_width) * static_cast<float>(window->width()));
+			if(component->width().index() == 1)
+				width = static_cast<int>(std::get<1>(component->width()) * static_cast<float>(_window->width()));
 			else
-				width = std::get<0>(component->size_width);
-			if(component->size_height.index() == 1)
-				height = static_cast<int>(std::get<1>(component->size_height) * static_cast<float>(window->height()));
+				width = std::get<0>(component->width());
+			if(component->height().index() == 1)
+				height = static_cast<int>(std::get<1>(component->height()) * static_cast<float>(_window->height()));
 			else
-				height = std::get<0>(component->size_height);
+				height = std::get<0>(component->height());
 		}
 		return {width, height};
 	};
@@ -65,7 +66,7 @@ std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_ind
 			std::tie(child_width, child_height) = get_child_size(index);
 			if(child_height > max_height)
 				max_height = child_height;
-			if(x != initial_x && x + child_width > window->width())
+			if(x != initial_x && x + child_width > _window->width())
 			{
 				x = initial_x + child_width;
 				y += max_height;
@@ -77,7 +78,7 @@ std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_ind
 		if(components[child_index] != nullptr)
 		{
 			std::tie(child_width, child_height) = get_child_size(child_index);
-			if(x != initial_x && x + child_width > window->width())
+			if(x != initial_x && x + child_width > _window->width())
 			{
 				x = initial_x;
 				y += max_height;
@@ -99,7 +100,7 @@ std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_ind
 			std::tie(child_width, child_height) = get_child_size(index);
 			if(child_width > max_width)
 				max_width = child_width;
-			if(y != initial_y && y + child_height > window->height())
+			if(y != initial_y && y + child_height > _window->height())
 			{
 				y = initial_y + child_height;
 				x += max_width;
@@ -111,7 +112,7 @@ std::tuple<int, int> uui::GlFlex::get_child_position(const std::size_t child_ind
 		if(components[child_index] != nullptr)
 		{
 			std::tie(child_width, child_height) = get_child_size(child_index);
-			if(y != initial_y && y + child_height > window->height())
+			if(y != initial_y && y + child_height > _window->height())
 			{
 				y = initial_y;
 				x += max_width;
diff --git a/src/uui/opengl/font_manager.cpp b/src/uui/opengl/font_manager.cpp
index 974ff23..18e67f8 100644
--- a/src/uui/opengl/font_manager.cpp
+++ b/src/uui/opengl/font_manager.cpp
@@ -131,7 +131,7 @@ void uui::GlFontManager::deinit()
 	initialized = false;
 }
 
-const uui::GlFontManager::Font& uui::GlFontManager::init_font(const std::string& font_path, std::size_t font_size)
+const uui::GlFontManager::Font& uui::GlFontManager::init_font(const std::string& font_path, unsigned int font_size)
 {
 	fonts.emplace_back();
 	auto& font = fonts.back();
@@ -173,7 +173,7 @@ const uui::GlFontManager::Font& uui::GlFontManager::init_font(const std::string&
 	glLinkProgram(gl_program);
 
 	// Create a texture that will be used to hold all ASCII glyphs
-	glActiveTexture(Config::FONT_TEXTURE_UNIT);
+	glActiveTexture(GlConfig::FONT_TEXTURE_UNIT);
 	glGenTextures(1, &font.atlas_texture);
 	glBindTexture(GL_TEXTURE_2D, font.atlas_texture);
 
@@ -257,7 +257,7 @@ void uui::GlFontManager::render_text(
 	glGetIntegerv(GL_CURRENT_PROGRAM, (GLint*)(&gl_prev_program));
 	glUseProgram(gl_program);
 
-	glActiveTexture(Config::FONT_TEXTURE_UNIT);
+	glActiveTexture(GlConfig::FONT_TEXTURE_UNIT);
 	auto [color_r, color_g, color_b, color_a] = text_color;
 	glUniform4f(glGetUniformLocation(gl_program, "textColor"), color_r, color_g, color_b, color_a);
 	glBindVertexArray(gl_vao);
diff --git a/src/uui/opengl/label.cpp b/src/uui/opengl/label.cpp
index 7003b7d..46aee62 100644
--- a/src/uui/opengl/label.cpp
+++ b/src/uui/opengl/label.cpp
@@ -14,25 +14,27 @@ uui::GlLabel::GlLabel(
 	if constexpr(uui::Application::debug_mode)
 		std::cout << "Creating GlLabel " << parent_index << std::endl;
 
+	_type = ComponentType::LABEL;
+
 	font_index = 0;
 	std::tie(text_width, text_height) =
 		window->font_manager->get_text_size(text, window->font_manager->fonts[font_index], 1.0f, 1.0f);
-	size_width = text_width;
-	size_height = text_height;
-	coord_all_relative = false;
+	_width = text_width;
+	_height = text_height;
+	_coord_all_relative = false;
 }
 
 void uui::GlLabel::render()
 {
-	float text_x = position_x.index() == 1 ? std::get<1>(position_x) * static_cast<float>(window->width())
-										   : static_cast<float>(std::get<0>(position_x));
-	float text_y = position_y.index() == 1 ? std::get<1>(position_y) * static_cast<float>(window->height())
-										   : static_cast<float>(std::get<0>(position_y));
+	float text_x = _position_x.index() == 1 ? std::get<1>(_position_x) * static_cast<float>(_window->width())
+										   : static_cast<float>(std::get<0>(_position_x));
+	float text_y = _position_y.index() == 1 ? std::get<1>(_position_y) * static_cast<float>(_window->height())
+										   : static_cast<float>(std::get<0>(_position_y));
 	text_y += static_cast<float>(text_height) - 1;
 
 	glBindVertexArray(gl_vao);
 	glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)0);
-	window->font_manager->render_text(
-		text.c_str(), window->font_manager->fonts.front(), text_x, text_y, 1.0f, 1.0f, text_color);
+	_window->font_manager->render_text(
+		text.c_str(), _window->font_manager->fonts.front(), text_x, text_y, 1.0f, 1.0f, text_color);
 	glBindVertexArray(0);
 }
diff --git a/src/uui/opengl/stack.cpp b/src/uui/opengl/stack.cpp
index f736185..a6e1eed 100644
--- a/src/uui/opengl/stack.cpp
+++ b/src/uui/opengl/stack.cpp
@@ -13,15 +13,16 @@ uui::GlStack::GlStack(
 	if constexpr(uui::GlApplication::debug_mode)
 		std::cout << "Creating GlStack " << parent_index << std::endl;
 
+	_type = ComponentType::STACK;
+
 	direction = params.direction;
 
-	type = Type::STACK;
-	coord_all_relative = false;
+	_coord_all_relative = false;
 }
 
 void uui::GlStack::create_component(const StackComponentParams& params, uui::InitFunction<uui::Component> init)
 {
-	if(!initialized)
+	if(!_initialized)
 		throw std::runtime_error("GlWindow error : cannot create component while not initialized");
 
 	glfwMakeContextCurrent(gl_window->glfw_window);
@@ -30,7 +31,7 @@ void uui::GlStack::create_component(const StackComponentParams& params, uui::Ini
 		components.size(), {0, 0, params.width, params.height}));
 	push_child(component);
 	component->init();
-	std::tie(component->position_x, component->position_y) = get_child_position(components.size() - 1);
+	std::tie(component->_position_x, component->_position_y) = get_child_position(components.size() - 1);
 	gl_window->components.push_back(component);
 
 	if(component != nullptr)
@@ -39,7 +40,7 @@ void uui::GlStack::create_component(const StackComponentParams& params, uui::Ini
 
 void uui::GlStack::create_label(const StackLabelParams& params, uui::InitFunction<uui::Label> init)
 {
-	if(!initialized)
+	if(!_initialized)
 		throw std::runtime_error("GlWindow error : cannot create component while not initialized");
 
 	glfwMakeContextCurrent(gl_window->glfw_window);
@@ -48,7 +49,7 @@ void uui::GlStack::create_label(const StackLabelParams& params, uui::InitFunctio
 		components.size(), {0, 0, params.text, params.text_color}));
 	push_child(std::static_pointer_cast<uui::GlComponent>(label));
 	label->init();
-	std::tie(label->position_x, label->position_y) = get_child_position(components.size() - 1);
+	std::tie(label->_position_x, label->_position_y) = get_child_position(components.size() - 1);
 	gl_window->components.push_back(label);
 
 	if(label != nullptr && init != nullptr)
@@ -57,10 +58,10 @@ void uui::GlStack::create_label(const StackLabelParams& params, uui::InitFunctio
 
 std::tuple<int, int> uui::GlStack::get_child_position(const std::size_t child_index) const
 {
-	int x = position_x.index() == 0 ? std::get<0>(position_x)
-									: static_cast<int>(std::get<1>(position_x) * static_cast<float>(window->width()));
-	int y = position_y.index() == 0 ? std::get<0>(position_y)
-									: static_cast<int>(std::get<1>(position_y) * static_cast<float>(window->height()));
+	int x = _position_x.index() == 0 ? std::get<0>(_position_x)
+									: static_cast<int>(std::get<1>(_position_x) * static_cast<float>(_window->width()));
+	int y = _position_y.index() == 0 ? std::get<0>(_position_y)
+									: static_cast<int>(std::get<1>(_position_y) * static_cast<float>(_window->height()));
 
 	if(child_index == 0)
 		return {x, y};
@@ -73,10 +74,10 @@ std::tuple<int, int> uui::GlStack::get_child_position(const std::size_t child_in
 			if(components[index] != nullptr)
 			{
 				auto& component = components[index];
-				if(component->size_width.index() == 1)
-					x += static_cast<int>(std::get<1>(component->size_width) * static_cast<float>(window->width()));
+				if(component->width().index() == 1)
+					x += static_cast<int>(std::get<1>(component->width()) * static_cast<float>(_window->width()));
 				else
-					x += std::get<0>(component->size_width);
+					x += std::get<0>(component->width());
 			}
 	}
 	else
@@ -86,10 +87,10 @@ std::tuple<int, int> uui::GlStack::get_child_position(const std::size_t child_in
 			if(components[index] != nullptr)
 			{
 				auto& component = components[index];
-				if(component->size_height.index() == 1)
-					y += static_cast<int>(std::get<1>(component->size_height) * static_cast<float>(window->height()));
+				if(component->height().index() == 1)
+					y += static_cast<int>(std::get<1>(component->height()) * static_cast<float>(_window->height()));
 				else
-					y += std::get<0>(component->size_height);
+					y += std::get<0>(component->height());
 			}
 		}
 	}
diff --git a/src/uui/opengl/window.cpp b/src/uui/opengl/window.cpp
index 6fd60d0..a139ba7 100644
--- a/src/uui/opengl/window.cpp
+++ b/src/uui/opengl/window.cpp
@@ -86,10 +86,20 @@ void uui::GlWindow::glfw_key_callback(
 		glfwSetWindowShouldClose(window, true);
 }
 
+// void uui::GlWindow::glfw_mouse_button_callback(GLFWwindow* window, int button, int action, int mods)
+// {
+// 	if (button == GLFW_MOUSE_BUTTON_LEFT && action == GLFW_PRESS)
+// 	{}
+// }
+
 uui::GlWindow::GlWindow(std::shared_ptr<uui::Application> app, int width, int height, const std::string& title)
 {
+	_type = ComponentType::WINDOW;
+
 	_app = app;
 	_initialized = false;
+
+	_title = title;
 	_width = width;
 	_height = height;
 	_render_needed = true;
@@ -98,18 +108,16 @@ uui::GlWindow::GlWindow(std::shared_ptr<uui::Application> app, int width, int he
 
 	if constexpr(uui::Application::debug_mode)
 		std::cout << "Creating GlWindow : " << title << std::endl;
-	this->title = title;
-	type = Type::WINDOW;
 }
 
 uui::GlWindow::~GlWindow()
 {
 	if constexpr(uui::Application::debug_mode)
-		std::cout << "Destructor GlWindow : " << title << std::endl;
+		std::cout << "Destructor GlWindow : " << _title << std::endl;
 	if(_initialized)
 	{
 		if constexpr(uui::Application::debug_mode)
-			std::cout << "Destructor-deinit GlWindow : " << title << std::endl;
+			std::cout << "Destructor-deinit GlWindow : " << _title << std::endl;
 		deinit();
 	}
 }
@@ -122,7 +130,7 @@ void uui::GlWindow::init()
 	gl_font_manager = std::make_shared<uui::GlFontManager>();
 	font_manager = std::static_pointer_cast<uui::FontManager>(gl_font_manager);
 
-	glfw_window = glfwCreateWindow(_width, _height, title.c_str(), NULL, NULL);
+	glfw_window = glfwCreateWindow(_width, _height, _title.c_str(), NULL, NULL);
 	if(glfw_window == NULL)
 		throw std::runtime_error("GLWindow : failed to create GLFW window");
 	glfwMakeContextCurrent(glfw_window);
@@ -234,7 +242,7 @@ void uui::GlWindow::deinit()
 		throw std::runtime_error("GlWindow error : calling deinit while not initialized");
 
 	if constexpr(uui::GlApplication::debug_mode)
-		std::cout << "Deinit GlWindow : " << title << std::endl;
+		std::cout << "Deinit GlWindow : " << _title << std::endl;
 
 	glfwMakeContextCurrent(glfw_window);
 	glDeleteProgram(gl_program);