diff --git a/Makefile b/Makefile
index 06595e8..78cc18a 100644
--- a/Makefile
+++ b/Makefile
@@ -1,2 +1,10 @@
-all: recursive.cpp
-	g++ $< -Iraylib -lraylib -o piskvorky
+CPP_FILES = \
+	    graphics.cpp \
+	    block.cpp \
+	    recursive.cpp
+
+HPP_FILES = \
+	    global.hpp
+
+all: $(CPP_FILES) $(HPP_FILES)
+	g++ $(CPP_FILES) -Iraylib -lraylib -o piskvorky
diff --git a/block.cpp b/block.cpp
new file mode 100644
index 0000000..a2aecbe
--- /dev/null
+++ b/block.cpp
@@ -0,0 +1,121 @@
+#include "global.hpp"
+
+Block::Block(int _depth, Rectangle trg) {
+	place = trg;
+	int x = trg.x, y = trg.y, w = trg.width, h = trg.height;
+	depth = _depth;
+	if(depth > 0)
+		for(int i = 0; i < 9; i++)
+			sons[i] = new Block( depth-1, get_son_rectangle(i) );
+}
+Rectangle Block::get_son_rectangle(int son) {
+	return {
+		float(int(place.x + place.width/3 * (son%3))),
+		float(int(place.y + place.height/3 * int(son/3))),
+		float(int(place.width/3)),
+		float(int(place.height/3))
+	};
+}
+int Block::set(tile pl) {
+	t = pl;
+	if(pl == empty)
+		return OKAY;
+	return CHANGE;
+}
+bool Block::playable(deque<int> v) {
+	if(depth == 0 && t == empty)
+		return true;
+	if(t != empty || v.size() == 0)
+		return false;
+	int son = v.front();
+	v.pop_front();
+	return sons[son]->playable(v);
+}
+int Block::play(deque<int> v, tile pl) {
+	if(t != empty)
+		return v.size();
+	if(depth == 0)
+		return set(pl);
+	if(v.size() == 0)
+		return OKAY;
+
+	int son = v.front();
+	v.erase(v.begin());
+	int rv = sons[son]->play(v, pl);
+
+	if(rv == CHANGE)
+		return set(update());
+	return rv;
+}
+bool Block::check_tie() {
+	bool is_tie = true;
+	for(Block* s : sons)
+		if(s->t == empty)
+			is_tie = false;
+	return is_tie;
+}
+tile Block::update() {
+	tile d1 = sons[0]->t, d2 = sons[2]->t;
+	for(int k = 0; k < 3; k++) {
+		tile row = sons[k*3]->t, col = sons[k%3]->t;
+		for(int i = 0; i < 3; i++) {
+			if(sons[k*3 + i]->t != row)
+				row = empty;
+			if(sons[k%3 + i*3]->t != col)
+				col = empty;
+		}
+		if(row != empty)
+			return row;
+		if(col != empty)
+			return col;
+		if(sons[k*4]->t != sons[0]->t)
+			d1 = empty;
+		if(sons[(k+1)*2]->t != sons[2]->t)
+			d2 = empty;
+	}
+	if(d1 != empty)
+		return d1;
+	if(d2 != empty)
+		return d2;
+
+	if(check_tie())
+		return tie;
+
+	return empty;
+}
+Rectangle Block::getRect(deque<int> v) {
+	if(v.size() == 0)
+		return place;
+	else {
+		int index = v.front();
+		v.pop_front();
+		return sons[index]->getRect(v);
+	}
+}
+void Block::updateRect(Rectangle trg) {
+	place = trg;
+	if(depth == 0)
+		return;
+	for(int i = 0; i < 9; i++)
+		sons[i]->updateRect(get_son_rectangle(i));
+}
+
+void Block::save(vector<tile> *r) {
+	if(depth == 0)
+		r->push_back(t);
+	else
+		for(Block* son : sons)
+			son->save(r);
+}
+void Block::load_state(vector<tile> state, int pos) {
+	if(depth == 0)
+		t = state[pos];
+	else {
+		for(int i = 0; i < 9; i++)
+			sons[i]->load_state(state, pos*9+i);
+		t = update();
+	}
+}
+void Block::undo(deque<int> &prev) {
+	// TODO
+}
diff --git a/global.hpp b/global.hpp
new file mode 100644
index 0000000..7ab5f28
--- /dev/null
+++ b/global.hpp
@@ -0,0 +1,72 @@
+#pragma once
+
+#include <iostream>
+#include <fstream>
+#include <array>
+#include <vector>
+#include <deque>
+#include <string>
+#include <raylib.h>
+
+using std::deque;
+using std::string;
+using std::array;
+using std::vector;
+
+using std::cin;
+using std::cout;
+
+#define FPS 15
+#define SCREEN 800
+#define LINE_W 2
+
+#define IMG_COUNT 2
+
+enum tile {empty = 0, p1 = 1, p2 = 2, tie = 3};
+#define OKAY -1
+#define CHANGE -2
+
+
+tile act(int t);
+tile pas(int t);
+Color col(int t);
+
+struct Block {
+	tile t = empty;
+	int depth;
+	Rectangle place;
+	array<Block*, 9> sons;
+
+	Block() {}
+	Block(int _depth, Rectangle trg);
+	Rectangle get_son_rectangle(int son);
+	int set(tile pl);
+	bool playable(deque<int> v);
+	int play(deque<int> v, tile pl);
+	bool check_tie();
+	tile update();
+	Rectangle getRect(deque<int> v);
+	void updateRect(Rectangle trg);
+
+	void save(vector<tile> *r);
+	void load_state(vector<tile> state, int pos);
+	void undo(deque<int> &prev);
+};
+
+void update(int &time, deque<int> &turn, Block* root, Rectangle &dst);
+void undo(Block *root, deque<int> &prev, Rectangle &dst, int &time);
+bool valid(Block* root, Rectangle &dst, deque<int> &turn);
+
+class Renderer {
+	array<Texture2D, IMG_COUNT> textures;
+	Block *root;
+
+	void prepareTextures();
+
+public:
+	void renderImage(tile t, Rectangle dst, Color color = WHITE);
+	void render_all(Block* root, int time, Rectangle play_area, deque<int> highlight = {});
+	void render_block(Block *b);
+	int update_board_size(int depth);
+	void prepare_screen(Block* root, int time, Rectangle dst);
+};
diff --git a/graphics.cpp b/graphics.cpp
new file mode 100644
index 0000000..b68dc28
--- /dev/null
+++ b/graphics.cpp
@@ -0,0 +1,59 @@
+#include "global.hpp"
+
+
+// Rendering
+void Renderer::prepareTextures() {
+	const char* paths[] = {"img/circle.png", "img/cross.png"};
+	for(int i = 0; i < IMG_COUNT; i++) {
+		Image img;
+		img = LoadImage(paths[i]);
+		textures[i] = LoadTextureFromImage(img);
+	}
+}
+void Renderer::renderImage(tile t, Rectangle dst, Color color) {
+	if(t == empty || t == tie)
+		return;
+	Texture tex = textures[t-1];
+	Rectangle src = {0, 0, (float)tex.width, (float)tex.height};
+	DrawTexturePro(textures[t-1], src, dst, {0,0}, 0, color);
+}
+void Renderer::render_block(Block *b) {
+	if(b->depth > 0)
+		DrawRectangleLinesEx(b->place, b->depth, BLACK);
+	renderImage(b->t, b->place);
+	if(b->depth == 0 || (b->t != empty && b->t != tie))
+		return;
+
+	for(int i = 0; i < 9; i++)
+		render_block(b->sons[i]);
+}
+void Renderer::render_all(Block* root, int time, Rectangle play_area, deque<int> highlight) {
+	BeginDrawing();
+	ClearBackground(RAYWHITE);
+
+	render_block(root);
+	if(valid(root, play_area, highlight))
+		renderImage(act(time), root->getRect(highlight), BLACK);
+	DrawRectangleLinesEx(play_area, 3*LINE_W, col(time+1));
+
+	EndDrawing();
+}
+int Renderer::update_board_size(int depth) {
+	int max_size = std::min(GetScreenWidth(), GetScreenHeight());
+
+	int size = 1;
+	for(int i = 0; i < depth; i++)
+		size *= 3;
+	
+	max_size -= max_size % size;
+	return max_size;
+}
+void Renderer::prepare_screen(Block* root, int time, Rectangle dst) {
+	SetConfigFlags(FLAG_WINDOW_RESIZABLE);
+	InitWindow(SCREEN, SCREEN, "Rekurze");
+	SetTargetFPS(FPS);
+	prepareTextures();
+	render_all(root, time, dst);
+}
+
+
diff --git a/piskvorky b/piskvorky
new file mode 100755
index 0000000..eb8971a
Binary files /dev/null and b/piskvorky differ
diff --git a/recursive.cpp b/recursive.cpp
index 937efc3..06a31b5 100644
--- a/recursive.cpp
+++ b/recursive.cpp
@@ -1,72 +1,10 @@
-#include <iostream>
-#include <fstream>
-#include <array>
-#include <vector>
-#include <deque>
-#include <string>
-#include <raylib.h>
+#include "global.hpp"
 
-using std::deque;
-using std::string;
-using std::array;
-using std::vector;
 
-using std::cin;
-using std::cout;
-
-enum tile {empty = 0, p1 = 1, p2 = 2, tie = 3};
 tile act(int t) { return (t % 2) ? p2 : p1; }
 tile pas(int t) { return (t % 2) ? p1 : p2; }
 Color col(int t) { return act(t) == p2 ? BLUE : RED; }
 
-#define FPS 15
-#define SCREEN 800
-#define LINE_W 2
-
-// Images
-#define IMG_COUNT 2
-array<Texture2D, IMG_COUNT> textures;
-void prepareTextures() {
-	const char* paths[] = {"img/circle.png", "img/cross.png"};
-	for(int i = 0; i < IMG_COUNT; i++) {
-		Image img;
-		img = LoadImage(paths[i]);
-		textures[i] = LoadTextureFromImage(img);
-	}
-}
-void renderImage(tile t, Rectangle dst, Color color = WHITE) {
-	if(t == empty || t == tie)
-		return;
-	Texture tex = textures[t-1];
-	Rectangle src = {0, 0, (float)tex.width, (float)tex.height};
-	DrawTexturePro(textures[t-1], src, dst, {0,0}, 0, color);
-}
-
-struct pos {
-	int x, y;
-	pos() : x(-1), y(-1) {}
-	pos(int px, int py) : x(px), y(py) {}
-	pos(Vector2 v) : x(v.x), y(v.y) {}
-
-	pos operator/(int a) {return {x/a, y/a};};
-	pos operator%(int a) {return {x%a, y%a};};
-
-	int to_int() { return 3*y + x; }
-	deque<int> to_deque(int depth, int screenSize) {
-		deque<int> r = {};
-		pos pp = pos(x,y);
-		if(pp.x > screenSize || pp.y > screenSize)
-			return {};
-
-		for(int i = 0; i < depth; ++i) {
-			screenSize /= 3;
-			pos ppos = pp/screenSize;
-			r.push_back(ppos.to_int());
-			pp = pp%screenSize;
-		}
-		return r;
-	}
-};
 
 deque<int> to_deque(Vector2 v, int depth, int size) {
 	deque<int> r = {};
@@ -84,148 +22,6 @@ deque<int> to_deque(Vector2 v, int depth, int size) {
 	return r;
 }
 
-#define OKAY -1
-#define CHANGE -2
-class Block {
-	tile t = empty;
-	Rectangle place;
-	int depth;
-	array<Block*, 9> sons;
-
-public:
-	Block() {}
-	Block(int _depth, Rectangle trg) {
-		place = trg;
-		int x = trg.x, y = trg.y, w = trg.width, h = trg.height;
-		depth = _depth;
-		if(depth > 0)
-			for(int i = 0; i < 9; i++)
-				sons[i] = new Block( depth-1, get_son_rectangle(i) );
-	}
-	Rectangle get_son_rectangle(int son) {
-		return {
-			float(int(place.x + place.width/3 * (son%3))),
-			float(int(place.y + place.height/3 * int(son/3))),
-			float(int(place.width/3)),
-			float(int(place.height/3))
-		};
-	}
-	int change(tile pl) {
-		t = pl;
-		if(pl == empty)
-			return OKAY;
-		return CHANGE;
-	}
-	bool playable(deque<int> v) {
-		if(depth == 0 && t == empty)
-			return true;
-		if(t != empty || v.size() == 0)
-			return false;
-		int son = v.front();
-		v.pop_front();
-		return sons[son]->playable(v);
-	}
-	int play(deque<int> v, tile pl) {
-		if(t != empty)
-			return v.size();
-		if(depth == 0)
-			return change(pl);
-		if(v.size() == 0)
-			return OKAY;
-
-		int son = v.front();
-		v.erase(v.begin());
-		int rv = sons[son]->play(v, pl);
-
-		if(rv == CHANGE)
-			return change(check_win());
-		return rv;
-	}
-	bool check_tie() {
-		bool is_tie = true;
-		for(Block* s : sons)
-			if(s->t == empty)
-				is_tie = false;
-		return is_tie;
-	}
-	tile check_win() {
-		tile d1 = sons[0]->t, d2 = sons[2]->t;
-		for(int k = 0; k < 3; k++) {
-			tile row = sons[k*3]->t, col = sons[k%3]->t;
-			for(int i = 0; i < 3; i++) {
-				if(sons[k*3 + i]->t != row)
-					row = empty;
-				if(sons[k%3 + i*3]->t != col)
-					col = empty;
-			}
-			if(row != empty)
-				return row;
-			if(col != empty)
-				return col;
-			if(sons[k*4]->t != sons[0]->t)
-				d1 = empty;
-			if(sons[(k+1)*2]->t != sons[2]->t)
-				d2 = empty;
-		}
-		if(d1 != empty)
-			return d1;
-		if(d2 != empty)
-			return d2;
-
-		if(check_tie())
-			return tie;
-
-		return empty;
-	}
-	void render() {
-		if(depth > 0)
-			DrawRectangleLinesEx(place, depth, BLACK);
-		renderImage(t, place);
-		if(depth == 0 || (t != empty && t != tie))
-			return;
-
-		for(int i = 0; i < 9; i++)
-			sons[i]->render();
-	}
-	Rectangle getRect(deque<int> v) {
-		if(v.size() == 0)
-			return place;
-		else {
-			int index = v.front();
-			v.pop_front();
-			return sons[index]->getRect(v);
-		}
-	}
-	void updateRect(Rectangle trg) {
-		place = trg;
-		int x = trg.x, y = trg.y,
-		    w = trg.width, h = trg.height;
-		if(depth == 0)
-			return;
-		for(int i = 0; i < 9; i++)
-			sons[i]->updateRect(get_son_rectangle(i));
-	}
-
-	void save(vector<tile> *r) {
-		if(depth == 0)
-			r->push_back(t);
-		else // TODO save?
-			for(Block* son : sons)
-				son->save(r);
-	}
-	void load_state(vector<tile> state, int pos) {
-		if(depth == 0)
-			t = state[pos];
-		else {
-			for(int i = 0; i < 9; i++)
-				sons[i]->load_state(state, pos*9+i);
-			t = check_win();
-		}
-	}
-	void undo(deque<int> &prev) {
-		// TODall: $(PAGES) ...O
-	}
-};
 
 void save_state(Block* root, int depth, int time, deque<int> &turn) {
 	vector<tile> state = {};
@@ -236,9 +32,11 @@ void save_state(Block* root, int depth, int time, deque<int> &turn) {
 
 	outfile << depth << "\n" << time << "\n" << turn.size() << "\n";
 
+	// Save turns
 	for(int play : turn)
 		outfile << play << std::endl;
 
+	// Save game state
 	for(tile t : state)
 		outfile << int(t) << std::endl;
 }
@@ -285,24 +83,6 @@ void undo(Block *root, deque<int> &prev, Rectangle &dst, int &time) {
 bool valid(Block* root, Rectangle &dst, deque<int> &turn) {
 	return CheckCollisionRecs(root->getRect(turn), dst) && root->playable(turn);
 }
-void render_all(Block* root, int time, Rectangle dst, deque<int> highlight = {}) {
-	BeginDrawing();
-	ClearBackground(RAYWHITE);
-
-	root->render();
-	if(valid(root, dst, highlight))
-		renderImage(act(time), root->getRect(highlight), BLACK);
-	DrawRectangleLinesEx(dst, 3*LINE_W, col(time+1));
-
-	EndDrawing();
-}
-void prepareScreen(Block* root, int time, Rectangle dst, int depth) {
-	SetConfigFlags(FLAG_WINDOW_RESIZABLE);
-	InitWindow(SCREEN, SCREEN, "Rekurze");
-	SetTargetFPS(FPS);
-	prepareTextures();
-	render_all(root, time, dst);
-}
 
 
 int main(int argc, char** argv) {
@@ -310,44 +90,41 @@ int main(int argc, char** argv) {
 	int time = 0, depth;
 	Block* root = nullptr;
 
-	int screenSize = SCREEN;
-
 	if(argc <= 1) {
 		cin >> depth;
-		root = new Block(depth, {0, 0, (float)screenSize, (float)screenSize});
+		root = new Block(depth, {0, 0, SCREEN, SCREEN});
 	}
 	else
 		load_state(&root, turn, depth, time, argv[1]);
 
-	Rectangle dst = root->getRect(turn);
+	Rectangle play_area = root->getRect(turn);
 
-	prepareScreen(root, time, dst, depth);
+	Renderer renderer;
+	renderer.prepare_screen(root, time, play_area);
+	int board_size = renderer.update_board_size(depth);
 
 	bool end = false;
 	deque<int> pturn = {};
 	while(!WindowShouldClose()) {
 		// Update screen size
-		screenSize = std::min(GetScreenWidth(), GetScreenHeight());
-		int size = 1;
-		while(size <= screenSize)
-			size *= 3;
-		screenSize = size/3;
-		float start_x = ((float)GetScreenWidth()-screenSize)/2;
-		float start_y = ((float)GetScreenHeight()-screenSize)/2;
+		board_size = renderer.update_board_size(depth);
 
-		root->updateRect({start_x, start_y, (float)screenSize, (float)screenSize});
-		dst = root->getRect(pturn);
+		float start_x = ((float)GetScreenWidth()-board_size)/2;
+		float start_y = ((float)GetScreenHeight()-board_size)/2;
+
+		root->updateRect({start_x, start_y, (float)board_size, (float)board_size});
+		play_area = root->getRect(pturn);
 
 		// Move
 		Vector2 touch = GetMousePosition();
-		turn = to_deque({touch.x - start_x, touch.y - start_y}, depth, screenSize);
-		if(IsMouseButtonPressed(0) && CheckCollisionPointRec(touch, dst) && valid(root, dst, turn)) {
+		turn = to_deque({touch.x - start_x, touch.y - start_y}, depth, board_size);
+		if(IsMouseButtonPressed(0) && CheckCollisionPointRec(touch, play_area) && valid(root, play_area, turn)) {
 			switch(root->play(turn, act(time))) {
 				case CHANGE:
 					end = true;
 					break;
 				case OKAY:
-					update(time, turn, root, dst);
+					update(time, turn, root, play_area);
 					pturn = turn;
 					break;
 			}
@@ -356,10 +133,11 @@ int main(int argc, char** argv) {
 		// Key presses
 		if(IsKeyPressed(KEY_X))
 			save_state(root, depth, time, turn), end = true;
-		else if(IsKeyPressed(KEY_Z)) {} //TODO undo
+		else if(IsKeyPressed(KEY_Z))
+			{} // TODO undo
 		
 		// Rendering
-		render_all(root, time, dst, turn);
+		renderer.render_all(root, time, play_area, turn);
 
 		if(end)
 			break;