diff --git a/src/kekengine/cpp/defaults.cpp b/src/kekengine/cpp/defaults.cpp
index c5e8c2a..2c11c46 100644
--- a/src/kekengine/cpp/defaults.cpp
+++ b/src/kekengine/cpp/defaults.cpp
@@ -40,12 +40,12 @@ void defaultInput(GLFWwindow *window, void *data) {
 }
 
 void init() {
-	keyForward = Input::createKeyMapping("Forward", GLFW_KEY_W);
-	keyBackward = Input::createKeyMapping("Backward", GLFW_KEY_S);
-	keyLeft = Input::createKeyMapping("Left", GLFW_KEY_A);
-	keyRight = Input::createKeyMapping("Right", GLFW_KEY_D);
-	keyUp = Input::createKeyMapping("Up", GLFW_KEY_SPACE);
-	keyDown = Input::createKeyMapping("Down", GLFW_KEY_LEFT_CONTROL);
+	keyForward = Input::createKeyBinding("Forward", GLFW_KEY_W);
+	keyBackward = Input::createKeyBinding("Backward", GLFW_KEY_S);
+	keyLeft = Input::createKeyBinding("Left", GLFW_KEY_A);
+	keyRight = Input::createKeyBinding("Right", GLFW_KEY_D);
+	keyUp = Input::createKeyBinding("Up", GLFW_KEY_SPACE);
+	keyDown = Input::createKeyBinding("Down", GLFW_KEY_LEFT_CONTROL);
 
 	Input::addPeriodicCallback(PeriodicCallback(defaultInput, nullptr));
 }
diff --git a/src/kekengine/cpp/engine.cpp b/src/kekengine/cpp/engine.cpp
index 7bfc84b..a5a3043 100644
--- a/src/kekengine/cpp/engine.cpp
+++ b/src/kekengine/cpp/engine.cpp
@@ -176,7 +176,7 @@ int init() {
 
 	Defaults::init();
 	fpsText = new TextElement(px(0), px(0));
-	//fpsText = new TextObject(new Font(KEK_DEFAULT_FONT), "HELLO WORLD!");
+	UI::addElement(fpsText);
 
 	return KEK_SUCCESS;
 }
@@ -237,7 +237,6 @@ int start() {
 
 			for(Light *light : shaderLights) {
 				ShaderLight shLight;
-				//shLight.color = light->color;
 				memcpy(shLight.color, glm::value_ptr(light->color), sizeof(shLight.color));
 				switch(light->getType()) {
 					case LightType::POINT:
@@ -270,7 +269,6 @@ int start() {
 				i++;
 			}
 
-			// TODO: Fix broken lights
 			glNamedBufferData(kekData.shader->lighting->ubo, kekData.shader->lighting->blockSize, &kekData.shader->lighting->buffer, GL_DYNAMIC_DRAW);
 			glBindBufferBase(GL_UNIFORM_BUFFER, KEK_UNIFORM_LIGHTS_BINDING, kekData.shader->lighting->ubo);
 
@@ -290,7 +288,10 @@ int start() {
 		int time = (int) (glfwGetTime() * 10);
 		if(time != prevTime) fpsText->setText("FPS: " + std::to_string((int) floor(1.0f / kekData.lastFrameTime)) + " (" + std::to_string(kekData.lastFrameTime * 1000) + " ms)");
 		prevTime = time;
-		fpsText->draw(UIPoint(0, 0), uiProjection);
+
+		for(UIElement *uiEl : kekData.uiElements) {
+			uiEl->drawAll(UIPoint(0, 0), uiProjection);
+		}
 
 		glDisable(GL_BLEND);
 		glEnable(GL_DEPTH_TEST);
diff --git a/src/kekengine/cpp/input.cpp b/src/kekengine/cpp/input.cpp
index 4144451..ce3f191 100644
--- a/src/kekengine/cpp/input.cpp
+++ b/src/kekengine/cpp/input.cpp
@@ -38,33 +38,33 @@ void removeMouseListener(InputListener listener) {
 	kekData.mouseCallbacks.erase(listener);
 }
 
-KeyMapping createKeyMapping(std::string name, GLFWKey defaultKey) {
-	if(name == KEK_INVALID_KEY_MAPPING_NAME) return KEK_INVALID_KEY_MAPPING;
-	KeyMapping id = nextID++;
-	KeyMappingData d;
+KeyBinding createKeyBinding(std::string name, GLFWKey defaultKey) {
+	if(name == KEK_INVALID_KEY_BINDING_NAME) return KEK_INVALID_KEY_BINDING;
+	KeyBinding id = nextID++;
+	KeyBindingData d;
 	d.name = name;
 	d.key = defaultKey;
-	kekData.keyMappings.emplace(id, d);
+	kekData.keyBindings.emplace(id, d);
 	return id;
 }
 
-void reassignKeyMapping(KeyMapping mapping, GLFWKey key) {
-	auto it = kekData.keyMappings.find(mapping);
-	if(it == kekData.keyMappings.end()) return;
-	KeyMappingData d = it->second;
+void reassignKeyBinding(KeyBinding mapping, GLFWKey key) {
+	auto it = kekData.keyBindings.find(mapping);
+	if(it == kekData.keyBindings.end()) return;
+	KeyBindingData d = it->second;
 	d.key = key;
 	it->second = d;
 }
 
-KeyMappingData getKeyMapping(KeyMapping mapping) {
-	auto it = kekData.keyMappings.find(mapping);
-	if(it == kekData.keyMappings.end()) return {.name = KEK_INVALID_KEY_MAPPING_NAME};
+KeyBindingData getKeyBinding(KeyBinding mapping) {
+	auto it = kekData.keyBindings.find(mapping);
+	if(it == kekData.keyBindings.end()) return {.name = KEK_INVALID_KEY_BINDING_NAME};
 	return it->second;
 }
 
-GLFWKeyState getKeyState(KeyMapping mapping) {
-	auto it = kekData.keyMappings.find(mapping);
-	if(it == kekData.keyMappings.end()) return -1;
+GLFWKeyState getKeyState(KeyBinding mapping) {
+	auto it = kekData.keyBindings.find(mapping);
+	if(it == kekData.keyBindings.end()) return -1;
 	return glfwGetKey(kekData.window, it->second.key);
 }
 
diff --git a/src/kekengine/cpp/ui.cpp b/src/kekengine/cpp/ui.cpp
index 60e6e8c..9ff0337 100644
--- a/src/kekengine/cpp/ui.cpp
+++ b/src/kekengine/cpp/ui.cpp
@@ -6,6 +6,32 @@
 
 namespace kek {
 
+constexpr UIValue &UIValue::operator+=(const UIValue& rhs) {
+	this->pixels += rhs.pixels;
+	this->parentWidth += rhs.parentWidth;
+	this->parentHeight += rhs.parentHeight;
+	this->screenWidth += rhs.screenWidth;
+	this->screenHeight += rhs.screenHeight;
+	return *this;
+}
+
+constexpr UIValue &UIValue::operator-=(const UIValue& rhs) {
+	this->pixels -= rhs.pixels;
+	this->parentWidth -= rhs.parentWidth;
+	this->parentHeight -= rhs.parentHeight;
+	this->screenWidth -= rhs.screenWidth;
+	this->screenHeight -= rhs.screenHeight;
+	return *this;
+}
+
+constexpr UIValue operator+(const UIValue& lhs, const UIValue& rhs) {
+	return UIValue(lhs) += rhs;
+}
+
+constexpr UIValue operator-(const UIValue& lhs, const UIValue& rhs) {
+	return UIValue(lhs) -= rhs;
+}
+
 Font *UIElement::defaultFont = nullptr;
 
 UIElement::UIElement(UIValue x, UIValue y): x(x), y(y) {
@@ -32,6 +58,10 @@ UIPoint UIElement::getScreenPosition() {
 	return pos;
 }
 
+std::vector<UIElement *> UIElement::getChildren() {
+	return children;
+}
+
 void UIElement::addChild(UIElement *child) {
 	children.push_back(child);
 }
@@ -182,4 +212,22 @@ void UIElement::init() {
 	defaultFont = new Font(KEK_DEFAULT_FONT);
 }
 
+void UI::addElement(UIElement *element) {
+	kekData.uiElements.push_back(element);
+}
+
+void UI::removeElement(UIElement *element) {
+	for(auto it = kekData.uiElements.begin(); it < kekData.uiElements.end(); it++) {
+		if(*it == element) {
+			kekData.uiElements.erase(it);
+			delete element;
+			break;
+		}
+	}
+}
+
+std::vector<UIElement *> UI::getElements() {
+	return kekData.uiElements;
+}
+
 }
diff --git a/src/kekengine/cpp/uielements.cpp b/src/kekengine/cpp/uielements.cpp
index f6ad967..8669b1c 100644
--- a/src/kekengine/cpp/uielements.cpp
+++ b/src/kekengine/cpp/uielements.cpp
@@ -137,4 +137,20 @@ void TextElement::draw(UIPoint screenPos, glm::mat4 projection) {
 	}
 }
 
+UIWindow::UIWindow(UIValue x, UIValue y): UIElement(x, y) {
+	addChild(new TextElement(x, y));
+}
+
+UIWindow::~UIWindow() {
+
+}
+
+UIElementType UIWindow::getType() {
+	return UIElementType::WINDOW;
+}
+
+void UIWindow::draw(UIPoint screenPos, glm::mat4 projection) {
+
+}
+
 }
diff --git a/src/kekengine/include/constants.h b/src/kekengine/include/constants.h
index 48dc7a1..795dba9 100644
--- a/src/kekengine/include/constants.h
+++ b/src/kekengine/include/constants.h
@@ -11,7 +11,7 @@
 
 #define KEK_UNIFORM_LIGHTS_BINDING 0
 
-#define KEK_LIGHT_LIMIT 64 // Also in shader/mesh/fragment.glsl
+#define KEK_LIGHT_LIMIT 64 // Also in shader/include/constants.glsl
 
 #define KEK_NOCLIP_SPEED 10.0f
 
@@ -24,8 +24,8 @@
 #define KEK_LIGHT_MAX_DISTANCE 30
 #define KEK_LIGHT_MAX_DISTANCE_SQUARED (KEK_LIGHT_MAX_DISTANCE * KEK_LIGHT_MAX_DISTANCE)
 
-#define KEK_INVALID_KEY_MAPPING_NAME "INVALID"
-#define KEK_INVALID_KEY_MAPPING -1
+#define KEK_INVALID_KEY_BINDING_NAME "INVALID"
+#define KEK_INVALID_KEY_BINDING -1
 
 #define KEK_FONT_RESOLUTION 64
 #define KEK_FONT_BITMAP_WIDTH_BLOCKS 16
diff --git a/src/kekengine/include/input.h b/src/kekengine/include/input.h
index b81f830..de54eea 100644
--- a/src/kekengine/include/input.h
+++ b/src/kekengine/include/input.h
@@ -14,10 +14,10 @@ typedef generic_callable_t<GLFWwindow *, double, double> MouseCallback; // mouse
 typedef unsigned int InputListener;
 typedef unsigned int GLFWKey;
 typedef unsigned int GLFWKeyState;
-typedef unsigned int KeyMapping;
+typedef unsigned int KeyBinding;
 typedef unsigned int GLFWMouseButton;
 
-struct KeyMappingData {
+struct KeyBindingData {
 	std::string name;
 	GLFWKey key;
 };
@@ -38,12 +38,12 @@ InputListener addMouseListener(MouseCallback callback);
 
 void removeMouseListener(InputListener listener);
 
-KeyMapping createKeyMapping(std::string name, GLFWKey defaultKey);
+KeyBinding createKeyBinding(std::string name, GLFWKey defaultKey);
 
-void reassignKeyMapping(KeyMapping mapping, GLFWKey key);
+void reassignKeyBinding(KeyBinding mapping, GLFWKey key);
 
-KeyMappingData getKeyMapping(KeyMapping mapping);
+KeyBindingData getKeyBinding(KeyBinding mapping);
 
-GLFWKeyState getKeyState(KeyMapping mapping);
+GLFWKeyState getKeyState(KeyBinding mapping);
 
 }
diff --git a/src/kekengine/include/internal.h b/src/kekengine/include/internal.h
index d2b36ca..96ebc7f 100644
--- a/src/kekengine/include/internal.h
+++ b/src/kekengine/include/internal.h
@@ -9,6 +9,7 @@
 #include "scene.h"
 #include "texture.h"
 #include "fonts.h"
+#include "ui.h"
 
 namespace kek {
 
@@ -16,7 +17,7 @@ struct KekData {
 	std::map<InputListener, PeriodicCallback> periodicCallbacks;
 	std::map<InputListener, KeyCallback> keyCallbacks;
 	std::map<InputListener, MouseCallback> mouseCallbacks;
-	std::map<KeyMapping, KeyMappingData> keyMappings;
+	std::map<KeyBinding, KeyBindingData> keyBindings;
 
 	GLFWwindow *window;
 	Shader *shader;
@@ -32,6 +33,8 @@ struct KekData {
 	std::map<std::string, std::weak_ptr<Texture>> loadedTextures;
 
 	FT_Library freetype;
+
+	std::vector<UIElement *> uiElements;
 };
 
 extern KekData kekData;
diff --git a/src/kekengine/include/ui.h b/src/kekengine/include/ui.h
index 15d8842..f10cec8 100644
--- a/src/kekengine/include/ui.h
+++ b/src/kekengine/include/ui.h
@@ -16,21 +16,13 @@ namespace kek {
 
 struct UIPoint {
 	int x, y;
-	UIPoint(int x, int y) {
-		this->x = x;
-		this->y = y;
-	}
+	UIPoint(int x, int y): x(x), y(y) {}
 };
 
 struct UIBounds {
 	int x, y, w, h;
 
-	UIBounds(int x, int y, int w, int h) {
-		this->x = x;
-		this->y = y;
-		this->w = w;
-		this->h = h;
-	}
+	UIBounds(int x, int y, int w, int h): x(x), y(y), w(w), h(h) {}
 
 	inline bool contains(UIPoint pos) {
 		return pos.x < x || pos.y < y || pos.x >= x + w || pos.y >= y + h;
@@ -38,6 +30,7 @@ struct UIBounds {
 };
 
 enum class UIElementType {
+	WINDOW,
 	RECTANGLE,
 	TEXT,
 	BUTTON,
@@ -153,6 +146,8 @@ public:
 	// Returns the element's position on the screen in pixels
 	UIPoint getScreenPosition();
 
+	std::vector<UIElement *> getChildren();
+
 	void addChild(UIElement *child);
 
 	void removeChild(UIElement *child);
@@ -200,4 +195,14 @@ public:
 
 };
 
+namespace UI {
+
+void addElement(UIElement *element);
+
+void removeElement(UIElement *element);
+
+std::vector<UIElement *> getElements();
+
+};
+
 }
diff --git a/src/kekengine/include/uielements.h b/src/kekengine/include/uielements.h
index cdcae9c..295a1b8 100644
--- a/src/kekengine/include/uielements.h
+++ b/src/kekengine/include/uielements.h
@@ -4,6 +4,18 @@
 
 namespace kek {
 
+class UIWindow: public UIElement {
+
+	UIWindow(UIValue x, UIValue y);
+
+	virtual ~UIWindow();
+
+	virtual UIElementType getType();
+
+	virtual void draw(UIPoint screenPos, glm::mat4 projection);
+
+};
+
 class TextElement: public UIElement {
 
 protected: