diff --git a/main.cpp b/main.cpp
index 0ed30c6..2bc4aec 100644
--- a/main.cpp
+++ b/main.cpp
@@ -17,6 +17,9 @@
 struct Mouse {
 	int x, y;
 	bool buttons[3];
+	bool mouse_down[3];
+	bool mouse_up[3];
+	bool mouse_old[3];
 };
 
 typedef bool(*LoopFun)(void);
@@ -56,14 +59,24 @@ unsigned char* map = nullptr;
 int map_x = 0;
 int map_y = 0;
 
+#define UNDO_MAX 16
+unsigned char* undo = nullptr;
+int undo_pointer = 0;
+int undo_min = 0;
+int undo_max = 0;
+
 int tile_sel = 0;
 int tile_back = 0;
 
 const char* GetPath(const char* filename) {
+#ifdef __APPLE__
     static char fullpath[400];
     strcpy(fullpath, path);
     strcat(fullpath, filename);
     return fullpath;
+#else
+	return filename;
+#endif
 }
 
 int StrToInt(const char* str) {
@@ -76,6 +89,35 @@ int StrToInt(const char* str) {
 	return val;
 }
 
+#define UndoInc(var) (var = (var+1)%UNDO_MAX)
+#define UndoDec(var) (var = (var-1+UNDO_MAX)%UNDO_MAX)
+void Undo_Create() {
+	unsigned char* dest = undo + (map_width*map_height*undo_pointer);
+	memcpy(dest, map, map_width*map_height);
+}
+void Undo_Restore() {
+	unsigned char* src = undo + (map_width*map_height*undo_pointer);
+	memcpy(map, src, map_width*map_height);
+}
+void Undo_Op() {
+	UndoInc(undo_pointer);
+	Undo_Create();
+	undo_max = undo_pointer;
+	if (undo_pointer == undo_min) UndoInc(undo_min);
+}
+void Undo_Undo() {
+	if (undo_pointer != undo_min) {
+		Undo_Restore();
+		UndoDec(undo_pointer);
+	}
+}
+void Undo_Redo() {
+	if (undo_pointer != undo_max) {
+		UndoInc(undo_pointer);
+		Undo_Restore();
+	}
+}
+
 void LoadConfig() {
 	FILE* f = fopen(GetPath("config.ini"), "r");
 	if (!f) { error = 1; return; }
@@ -113,7 +155,7 @@ void Init() {
 	LoadConfig();
 
 	SDL_Init(SDL_INIT_EVERYTHING);
-	sdlWindow = SDL_CreateWindow("Mappy v0.1", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, screen_width*zoom, screen_height*zoom, SDL_WINDOW_SHOWN);
+	sdlWindow = SDL_CreateWindow("Mappy v0.3", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, screen_width*zoom, screen_height*zoom, SDL_WINDOW_SHOWN);
 	sdlRenderer = SDL_CreateRenderer(sdlWindow, -1, SDL_RENDERER_PRESENTVSYNC);
 	SDL_SetRenderDrawBlendMode(sdlRenderer, SDL_BLENDMODE_BLEND);
 	SDL_RenderSetLogicalSize(sdlRenderer, screen_width, screen_height);
@@ -164,6 +206,7 @@ void Init() {
 
 	f = fopen(GetPath(map_filename), "rb");
 	map = (unsigned char*)malloc(map_width*map_height);
+	undo = (unsigned char*)malloc(map_width*map_height*UNDO_MAX);
 	if (f) {
 		int old_map_width = 0, old_map_height = 0;
 		fread(&old_map_width, 1, 1, f);
@@ -270,6 +313,14 @@ bool Update() {
 	mouse.x /= zoom;
 	mouse.y /= zoom;
 
+	mouse.mouse_down[0] = mouse.mouse_down[1] = mouse.mouse_down[2] = mouse.mouse_up[0] = mouse.mouse_up[1] = mouse.mouse_up[2] = false;
+	if ((buttons & 1) == 1) { if (!mouse.mouse_old[0]) mouse.mouse_down[0] = true; } else { if (mouse.mouse_old[0]) mouse.mouse_up[0] = true; }
+	if ((buttons & 2) == 2) { if (!mouse.mouse_old[1]) mouse.mouse_down[1] = true; } else { if (mouse.mouse_old[1]) mouse.mouse_up[1] = true; }
+	if ((buttons & 4) == 4) { if (!mouse.mouse_old[2]) mouse.mouse_down[2] = true; } else { if (mouse.mouse_old[2]) mouse.mouse_up[2] = true; }
+	mouse.mouse_old[0] = (buttons & 1) == 1;
+	mouse.mouse_old[1] = (buttons & 2) == 2;
+	mouse.mouse_old[2] = (buttons & 4) == 4;
+
 	if (buttons == 0) ignoreMouse = false;
 
 	if (buttons != 0 && !ignoreMouse) {
@@ -343,6 +394,44 @@ void DoTilePal() {
 	if (keyJustPressed == SDL_SCANCODE_Q) state = STATE_TILEMAP;
 }
 
+void floodfill_r(const int x, const int y, const int tile) {
+	const int width_in_tiles = screen_width / tile_width;
+	const int height_in_tiles = screen_height / tile_height;
+	if ( (keyboard[SDL_SCANCODE_LCTRL] )  || ( (x >= map_x && y >= map_y && x < (map_x + width_in_tiles) && y < (map_y + height_in_tiles)) ) ) {
+		if (map[x + y * map_width] == tile) {
+			map[x + y * map_width] = tile_sel;
+			floodfill_r(x + 1, y, tile);
+			floodfill_r(x - 1, y, tile);
+			floodfill_r(x, y + 1, tile);
+			floodfill_r(x, y - 1, tile);
+		}
+	}
+}
+
+void FloodFill() {
+	const int x = map_x + (mouse.x / tile_width);
+	const int y = map_y + (mouse.y / tile_height);
+	const int tile = map[x + y * map_width];
+	if (tile != tile_sel) floodfill_r(x, y, tile);
+}
+
+void ReplaceTile() {
+	const int x = map_x + (mouse.x / tile_width);
+	const int y = map_y + (mouse.y / tile_height);
+	const int tile = map[x + y * map_width];
+	const bool all_map = keyboard[SDL_SCANCODE_LCTRL];
+	const int xi = all_map ? 0 : map_x;
+	const int yi = all_map ? 0 : map_y;
+	const int w = all_map ? map_width : xi+(screen_width / tile_width);
+	const int h = all_map ? map_height : yi+(screen_height / tile_height);
+
+	for (int yy = yi; yy < h; yy++) {
+		for (int xx = xi; xx < w; xx++) {
+			if (map[xx + yy * map_width] == tile) map[xx + yy * map_width] = tile_sel;
+		}
+	}
+}
+
 void DoTileMap() {
 	static bool menu = false;
 
@@ -362,7 +451,8 @@ void DoTileMap() {
 		DrawRect(cur_x*tile_width - 1, cur_y*tile_height - 1, tile_width + 2, tile_height + 2, 255, 255, 255, 128);
 
 		if (keyJustPressed == SDL_SCANCODE_TAB) {
-			menu = true; return; }
+			menu = true; return;
+		}
 		if (keyJustPressed == SDL_SCANCODE_Q) state = STATE_TILEPAL;
 		if (keyJustPressed == SDL_SCANCODE_E) { state = STATE_MINIMAP; UpdateMiniMap(); }
 		if (keyJustPressed == SDL_SCANCODE_X) { int temp = tile_back; tile_back = tile_sel; tile_sel = temp; }
@@ -370,10 +460,19 @@ void DoTileMap() {
 		if (keyJustPressed == SDL_SCANCODE_LEFT || keyJustPressed == SDL_SCANCODE_A) if (map_x > 0) map_x -= width_in_tiles;
 		if (keyJustPressed == SDL_SCANCODE_DOWN || keyJustPressed == SDL_SCANCODE_S) if (map_y < map_height - height_in_tiles) map_y += height_in_tiles;
 		if (keyJustPressed == SDL_SCANCODE_UP || keyJustPressed == SDL_SCANCODE_W) if (map_y > 0) map_y -= height_in_tiles;
+		if (keyJustPressed == SDL_SCANCODE_F) { Undo_Op(); FloodFill(); }
+		if (keyJustPressed == SDL_SCANCODE_R) { Undo_Op(); ReplaceTile(); }
+
+		if (mouse.mouse_down[MOUSE_BUTTON_LEFT] || mouse.mouse_down[MOUSE_BUTTON_RIGHT]) { Undo_Op(); }
 		if (mouse.buttons[MOUSE_BUTTON_RIGHT]) { map[(map_x + cur_x) + (map_y + cur_y)*map_width] = tile_back; }
 		if (mouse.buttons[MOUSE_BUTTON_LEFT]) { map[(map_x + cur_x) + (map_y + cur_y)*map_width] = tile_sel; }
 		if (mouse.buttons[MOUSE_BUTTON_MIDDLE]) { tile_sel = map[(map_x + cur_x) + (map_y + cur_y)*map_width]; }
-	} else {
+
+		if (keyJustPressed == SDL_SCANCODE_Z && keyboard[SDL_SCANCODE_LCTRL]) { Undo_Undo(); }
+		if (keyJustPressed == SDL_SCANCODE_Y && keyboard[SDL_SCANCODE_LCTRL]) { Undo_Redo(); }
+		if (keyJustPressed == SDL_SCANCODE_Z && keyboard[SDL_SCANCODE_LCTRL] && keyboard[SDL_SCANCODE_LSHIFT]) { Undo_Redo(); }
+	}
+	else {
 		if (keyJustPressed == SDL_SCANCODE_TAB) { menu = false; return; }
 		FillRect(0, 0, screen_width, screen_height, 0, 0, 0, 192);
 		if (Button(6, 6, "Save")) {
@@ -385,6 +484,7 @@ void DoTileMap() {
 			menu = false; ignoreMouse = true;
 		}
 		if (Button(6, 24, "Clear")) {
+			Undo_Op();
 			for (int y = 0; y < height_in_tiles; y++) {
 				for (int x = 0; x < width_in_tiles; x++) {
 					 map[(map_x + x) + (map_y + y) * map_width] = tile_back;
@@ -393,6 +493,7 @@ void DoTileMap() {
 			menu = false; ignoreMouse = true;
 		}
 		if (Button(6, 42, "Border")) {
+			Undo_Op();
 			for (int y = 0; y < height_in_tiles; y++) {
 				map[(map_x) + (map_y + y) * map_width] = tile_sel;
 				map[(map_x + width_in_tiles - 1) + (map_y + y) * map_width] = tile_sel;
@@ -409,6 +510,7 @@ void DoTileMap() {
 #define mod(x, y) (((x % y)+y)%y)
 
 void ShiftMap(int sx, int sy) {
+	Undo_Op();
 	int test = mod(-1, 240);
 	sx *= (screen_width/tile_width);
 	sy *= (screen_height / tile_height);
@@ -447,6 +549,7 @@ void DoMiniMap() {
 	const int screen_height_in_tiles = screen_height / tile_height;
 	DrawRect((ox + map_x) - 1, (oy + map_y) - 1, screen_width_in_tiles + 2, screen_height_in_tiles + 2, 255, 255, 255);
 	//DrawRect(ox + (tile_sel % tiles_per_row)*tile_width - 1, oy + (tile_sel / tiles_per_row)*tile_height - 1, tile_width + 2, tile_height + 2, 255, 255, 255);
+	DrawRect(ox - 1, oy - 1, map_width + 2, map_height + 2, 255, 0, 0);
 	if (mouse.buttons[MOUSE_BUTTON_LEFT]) {
 		map_x = int((mouse.x-ox) / screen_width_in_tiles) * screen_width_in_tiles;
 		map_y = int((mouse.y - oy) / screen_height_in_tiles) * screen_height_in_tiles;